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    #31
    I'm going to complain for a minute:

    I have literally no room to work on things at all where I live. I'm crammed into a bike-shed, with just enough room to squeeze between my bakfiets and the next scoot-mobile. I always end up rushing through things--in order to avoid being in everyone else's way--so even if I end up with okay results, it's never quite as good as I want. What I wish I had, was an indoor space where I could work--preferably undisturbed--by people or mosquitoes.

    Okay. I'm not sure I feel any better, but there you have it.

    Now--in spite of whine-worthy working conditions, I'm going to need to go into action. There is much on my list of things I want to do:

    For the front two wheels:

    Install the new lockable e-bike brake handles I just got from Uncle Ali; replace both wheels outer brake cables; replace both inner brake cables, utilizing the Elvedes universal cable-splitter I got from my local vendor; adjust my front brakes to match one another, and to work with their parking brake. Then, pull the front-wheels off, bring them up to my room (and my cheap-ass but workable truing stand) and dish them about 3/8" or so, to better align them with their fenders. Once that's done, those larger tires can be mounted, then back on the bike the wheels go.

    For the back wheel:

    Install the other new lockable e-bike brake handle; replace the outer brake cables; adjust the rear drum brake; check condition of rear sprocket, check shifter-cable adjustment, and spoke tension.

    For the electrics:

    One at a time, I need to plug the display into each front-wheel's controller, and see if I can alter the settings (assuming--and hoping--the controllers will be able to remember my changes--and that they're not dependent on the screen itself--so my changes remain after I've unplugged the display).

    If that works, I want to experiment with my throttle signals. Try some stuff. Post here what happens.

    To supplement the electronics stuff, I have a lot of wiring coming up.

    Without the energy from the wheel-hub generators, I've got no lights at all. I'm tempted to experiment with the lights I have--which were all made for +/- 6 VAC--from the wheel-hub generators. But how picky will they be in reality? They're very inexpensive LED bicycle lights, but I don't think running similar DC voltages through them will cause any harm. My "brake-tech" rear-lamp won't do its thing anymore. It'd have to have that A/C signal--measuring that pulse-rate--in order to have its brake-light function. I'm going to keep those lights, even if I can't make them work with DC voltage.

    I have also vague plans to one day make a trailer for the bakfiets. If I put my old wheels underneath it, I'll be able to self-illuminate my trailer same as I used to do with the bakfiets.

    Mean-time, I have ordered new 12V LED floodlights, and I've already got turn-signals. Taillights are needed too, but I do want a brake-light function--at least for the center-rack light behind me--so I will try to figure out how to do that too.

    As if that's not enough to do, I also just got a package in the mail--something purely for my kids' enjoyment--a waterproof Bluetooth sound system (intended for motorcycles). Also I need to wire up a USB charger for my smart-phone (which serves as my navigation aid as well as dashboard for my Cyclone and my BMS). Fortunately, these items came all ready to go--heavy-duty wiring, waterproof connections, in-line blade terminals (also waterproof) and nice ring-terminals on the ends of the wires--ready to screw right onto distribution-buss-bars.

    More to follow...

    Tklop
    Last edited by tklop; 07-10-2018, 05:21 AM.

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      #32
      Small report; probably not very interesting:

      For my front-motors, I didn't want to have to use a display. So, I ordered my two front-motor's controllers with jumpers which take the place of the display for my front-motors' controllers.

      However, I wanted to be able to adjust them--so, I ordered a single display that I could just use as a programming device.

      Today, I tested out if it'd work or not. I wasn't sure if the controllers would "remember" the display's settings. I've gotten the impression reading various entries here, that in some systems, the display does all the "thinking and remembering" -- and in those systems, it sounds to me as if the controllers are just basically follow-along devices for the screens. So, I hoped my plans would work, but I wasn't going to be sure until I tried.

      To adjust the controller's settings, I first unplugged the jumper, plugged in the display, then powered it up. Following YouTube guidance for the relatively generic display, I set the wheel-size, then just scrolled through all the defaults, until I reached the setting to limit amperage--which I set to 50%. Then, I powered everything off again, removed the display, replaced the jumper, and moved on to the other front-wheel controller. Interestingly, the settings didn't require modification for the second controller--perhaps the screen sent them in automatically upon connection, but just to be sure, I still scrolled through each menu, and clicked the "okay" button to (re)register each of the selections in the menus. Then, I powered it off again, removed the display, plugged the jumper back in, then put the display back into the toolbox.

      Result: The controllers accepted and remembered the modifications I made to the settings, and did not care that the display had been removed.

      The front-motors do not do funky things involving speed-governing anymore. Gone too, is the asymmetrical pulling, even at max speed, cruise control or not. It's gone. My max speed (front-motors alone--real-world) is now +/- 28 KPH, and now seems more dependent on the motors' own limitations. It just seems they reach max RPM, and hold there. Smoothly, evenly. No more cycling on and off as speeds rise and fall--just steady. And yes, I realize for many of you that the pace is not crazy-fast--but that's exactly what I ordered. These motors were wound for higher torque, lower speeds after all. Plus, I've got them on 20 inch wheels, so they'd be faster on 26's or larger too.

      Though I've turned the amperage down, the motors aren't weakened noticeably. I may in fact need to reduce that number further. But for now, even with all three motors on max-throttle, I'm now remaining under the continuous 50A my BMS is designed to be delivering. I like soft settings, because they let me know that if ever there's an emergency situation and I need to really mash the throttles, that I'm going to get the absolute most my system can safely give me--and that I'm not going to start either a BMS or motor-controller fire.

      That's reassuring.

      I keep saying this. But it's really remarkable. Compared to before--with the Cyclone 4KW by itself--the machine rides so nicely now with its three-motor system, that it's hard to effectively describe. Though obviously like any other three-wheeled conveyance, it remains extremely prone to tipping over, for the most part, it's cornering has become a lot more stable. Still, corners which are "banked" the wrong way, or places where one must ride "along" a slope--those are still sketchy. But overall, the improvement is so profound, that I'm now completely convinced that this front-heavy beast-of-a-machine has truly come into its own with AWD.

      More to follow, I'm sure.

      Tklop
      Last edited by tklop; 07-12-2018, 03:04 PM. Reason: for clarity

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        #33
        My biggest drawback is the added battery drain--when it comes to the tri-motor.

        I think the advantages gained in stability and performance made AWD well worth doing, but it may mean an even bolder choice for my next battery (or maybe just set up a second one--as a range-extender).

        Also, I am planning next month to order another set of these hub-motors, but with disc-brakes. They should be enough for what I have, but I'm also running with more weight and power than an "average" bakfiets of my type. I'll restring the roller-brake versions--one into my city-bike's front-wheel; one into the front wheel of my ex's Giant Mio (mamafiets). I'll probably just order new batteries for them too, but I've thought about just taking apart my current one (it's still pretty new after all), and use it to power both bikes (my 16s 3p can turn into 3 each; 16s, or one 16s, and one 16s 2p).

        And now--I'm also beginning to wonder which forum I ought to be posting in... The beast began it's e-bike life as a Cyclone conversion--so I am hoping that as long as it's still got the mid-drive working on the rear-frame--it's cool to stay here...

        Maybe more. Maybe later!

        Tklop

        Comment


        • calfee20
          calfee20 commented
          Editing a comment
          I would leave it here. You have such an interesting bike that you should consider posting to endless sphere. I have really been enjoying reading about your build....calfee

        #34
        I think one day I need to condense this information down.

        I see that I repeat myself a lot, for one thing.

        This forum serves as my sounding-board, and this is the place where I go from dreaming up crazy ideas, to figuring out how to actually implement them. As I learn, the narrative evolves. I hope anyone reading along will keep this in mind, as they encounter my countless incongruities.

        I still am interested in experimenting with the idea of a dual-controller to operate the front two motors. These are the kinds of controllers used to power robots, or electric wheelchairs, etc. They're set up to provide electronic differential, which would honestly really be the last possible improvement to the way the bakfiets handles.

        Handling and stability:
        ----------------------------



        Preface:

        The Babboe Big bakfiets, is a tip-over prone top-heavy, front-heavy (and for that matter altogether heavy) kid-hauler/cargo-box-bike. The model comes in various configurations, for dog-owners, pizza or ice-cream delivery, or just for kids and groceries (like mine). The various models are also available with their factory-installed, wimpy geared hub motor in the rear-wheel. I do not imagine it gives you a lot of range, but I do see many of them out and about. It's doable--is the point--if you're willing to cough up that extra pile of cash--to get a ready-made, off-the-factory-floor e-bike version. What I have done, is purely voluntary. When all is said and done, and all my various conversions and mods are in-place, it's possible I'll have spent close to what that "factory model" costs--but I can do a lot more, and travel a lot further than their version--so there's no doubt about it: I've gotten one heck of a lot more for my money than I'd have gotten buying "pre-made". This posting will hopefully help explain more specifically why I feel that way about it.


        So, here's how Pythagoras begins as a rival, yet turns out to be a nervous ally in the end:

        The geometry of the Babboe Big in particular, is such, that the pivot-point for steering is exactly centered between the wheels, at the axles. But the coupling is also tilted slightly; as though the pivot-bolt were leaning forward. This angle, assures that as the box-portion is twisted left or right, the rear-frame also "leans" along (though only slightly--and not really enough to keep you from tipping over the other way). Because this is a "slight-but-inadequate lean", instead of being helpful, it actually further shifts the machine's weight (and the pilot's weight) naturally toward the outside-edge of the turn. Though it remains a problem--especially with negative road-camber--I've been able to compensate for this a little bit. Though I can't change the tilt-angle, by sitting higher, my weight shifts further inboard (though higher up) with a longer seat-post.

        The Babboe Big bakfiets comes standard with a pretty low saddle-height, and not a terribly long seat-post. Now, I am a little on the tall-side for an American, but pretty much dead-average in height--compared to Dutch men--but it's not made for only us. The Babboe Big is also made for women to pedal--that's why the seat is positioned fairly low. By using a longer seat-post (which required a spacer as well), I'm able to shift a little bit more weight with that "small-but-inadequate-tilt", which helps some--but I can also lean a little further, or if feeling extra bold, I can even "hang" a little bit off the inboard-side off of the bike as it goes through a curve, by standing on the inboard-side pedal (which feels really "wrong" according to all my cycling muscle memory) which helps shift some more weight away from the dangerous side. Hanging even further off the inside would be even more effective, I bet--but it's a super-duper deadly-sketchy idea. I mean--if one could practice it, learn to feel the balance of it--then yeah, it could be pulled-off regularly. But then--it begs the question--how do you practice something that is almost impossible to get right, and which will kill you (and maybe others too) if you get it wrong even once? Yeah--for now, I think I'll leave that trick for the stunt-men to figure out!

        When turning, geometry also dictates that the wheel on that outside edge of the turn, happens to also be further from the rear-wheel, as well as closer to the center-line of the bike. As the turn gets progressively sharper, this is exaggerated. The contact-points of the wheels always form a triangle, obviously. But when turning, the footprint goes from Equilateral to Isosceles--with the weight shifting to the least tip-resistant side; the longest of the triangle's three sides (and then, almost all the dynamic forces of turning exaggerate this weight-shift).

        In practical terms, that means its natural tendency is to under-steer. But because there isn't any suspension (except for tire mushiness), there's no way it can just start to skid, and "plow" forward like an under-steering car might. Instead, the three-wheeled Babboe Big bakfiets opts to deal with those forces in a simpler way--it just abruptly flips over on its side.

        Yes, a terrifying certainty awaits the unforewarned and inexperienced: Once a hapless Babboe Big pilot has entered into a corner "too fast" there is no way out. You're going to crash, and it's going to hurt. Best hope you ain't got kids in the box (or your dog).

        Which brings me around, to where I got my very first clue, which would eventually support the idea of adding the front-motors--as a means to help solve this instability; the notion of using the wheels to generate forces that could shifting the bike's weight in the opposite way to all those "trying-to-tip-me-over" forces...

        One day, still fairly early in my Bakfiets on-the-fly learning-curve, I found myself careening down a twisting curve. Already nearing maximum-controllable-speed, and knowing how touchy the front-brakes could be; I could sense the rapidly approaching ragged-edge of "too fast--time to crash" (thank goodness with no kids on board); and not having an anchor to toss over the side, I did the only thing left--I applied the rear brake in that turn... Mind-you, I didn't have high-hopes. The bike's drum-brakes are very strong, and the rear-brake alone can stop the machine. But from say 30 kilometers per hour, level ground, it'd probably take twenty meters (+/- 20 mph to stop in +/- 60 feet). No, it's not like I really expected a lot. But it gave me instantly a small, but noticeable extra measure of unexpected stability--and then less dramatic, but most importantly, I was able to keep my descent from gaining any more speed. That difference in stability wasn't immense--but quite a welcome and noticeable relief at that particular moment, believe me--and I took note of it.

        With practice, I found I could handle roughly 5% more speed entering a turn, if I used the rear-wheel to "brake through the turn". Of course I had no chance in hell to actually stop in such a turn--but it meant I now could still manage to swoop through in a pinch, without losing control.

        It seems, when you drive something this inherently unstable, every little compensation you discover, has the potential to give you another margin of safety--and each offers in its own way, the chance for slightly broader "operational limits. " Naturally, it seems you learn these little things by having to play "test pilot" in emergency situations--but after that, if you discover something useful, you either practice it intentionally, or you get a little more practice at them with every repeated emergency--but eventually, these skin-saving little control-enhancement techniques can be adopted as part of your repertoire--part of your own riding style...

        In terms of the forces involved, when I activated the rear-brake, having that drag-force coming from the rear-frame, meant it wasn't only pulling in a rearward plane--but also in a downward plane; working to tilt that box rearward--instead of forward. No, not by very much--but nonetheless, still shifting the bikes weight just a little bit rearward, just a wee-bit away from that outboard front-wheel, and back toward the rear-frame--just that teensy little-bit was enough to allow me to maintain control. By imagining those pulling-forces from the rear-brake being reversed, you can also see that pushing forces from the rear-frame, would work to worsen the inherent instability, while attempting to turn under power.

        Because so much of the turning-energy of the bakfiets is being transformed into "try-to-tip-me-over" energy--the front-wheels have to absorb a tremendous amount of strain, whenever I'm turning enough to "feel" the turn at all. The tires are constantly trying to "roll under" (especially the one on the outside of the turn); and the lateral-stresses I put on my wheels is (or must surely be) really huge. Often, in a curve, the bakfiets' inside-wheel will come off the ground (or float over potholes, etc). That's got to be an awful lot of lateral stress on the outside wheel--don't you imagine? Thank goodness for Ryde Andra 40 rims. 1/4 inch welded steel drop-outs! (I can get it up on two-wheels intentionally too, and even hold it there for a while--but it seems to scare other road-users).

        Remember the coupling's tilt-angle? Well, because it's "not quite enough" tilt to truly "coordinate" the steering-lean; it also means that any forward-pushing-forces from the rear-wheel aren't going to be "coordinated" with the turns either. Instead, those pushing-forces are working to shift their energy (and the bike's weight) even further toward the same outboard-edge wheels. Oh, yes. More tipping-over incentive--just what I need, right? That goes for leg-power, of course--but when you add a motor to the mix, well, the motor's greater forces provide a greater exaggeration of the same balance issues... Suffice to say, it's not ideal.

        I didn't start this project thinking I'd be able to solve the stability problems. I didn't even start out thinking electric at all--though you don't pedal one with legs alone for very long, before you start fantasizing about assist! That's when I discovered this forum, and started to lurk and learn. My non-powered kid-hauler bakfiets was already amassing a lot of good mid-drive components, simply through the process of trying with each replaced component, to make sure it was an "upgrade"-- to help get my setup as "heavy-duty" as I could make it--even if I was still just pedaling it with human-power. In the mean time, I continued for a few years fantasizing about converting the beast.

        After the wife booted me out, there wasn't any reason not to just go for it. So, I took the plunge. I knew, because of my design, that if I wanted to go mid-motor, only the Cyclone would fit my frame; and then I chose the Cyclone 4KW motor, because it's the most energy-efficient motor Cyclone makes--and I figured extra power is always nice to have on-tap. It's both beauty and beast!

        Going with the mid-motor, put that motor's weight further forward than a rear-wheel geared-hub motor would have been, but I felt that since I'm also alway sitting back there on the rear-frame, the weight-shift is probably negligible--just as is the lack of a battery on my rear-rack. I may be wiry, but I'm plenty heavy enough to hold the rear-frame down.

        What did shift weight to the box, was the +/- 30 kilogram battery. I tried to mount it so that its weight could be a help instead of a hindrance; placing it on the floor of the box, with most of its mass just rear of the axles. That proved successful, allowing maybe another 5% speed through the turns (assuming the involvement of no other top-heavy loads that might cancel the advantage).

        And then, of course, I introduced the front-wheel hub-motors: The wheel-motors added some weight to the front of the machine--right at the box's center of gravity--and low. This added a little more stability, allowing perhaps a little more speed through the bends. Even coasting, that's still a benefit.

        But when pulling, the wheel-hub motors (if you think about the forces involved) are teaming up together to tilt the box in the opposite direction of the wheels; trying like hell to tip that front-box backward; pushing that rear-wheel down; shifting the bike's weight rearward... Well--jeez. Whaddaya know! That's exactly counter to every one of those "tip-me-over" forces!

        So, yeah. That's the Great Big Gigantic Mega Factor in why I get so much extra stability from the front-wheel motors; the reactive forces produced (as they use their energy to pull the box forward) are aligned perfectly to counteract all those negative trying-to-tip-me-over forces. Jackpot! Eureka! Whoo, hoo!

        Now too, the Cyclone's energy can be spent more efficiently: Instead of trying to push the box forward (most inefficiently and against its own will, whenever turning--as I explained above), the rear-frame now takes on a totally different role. The rear-frame now, having been fully relieved of it's box-pushing duty, now acts simply as a self-propelled and stable anchor-seat for the operator, whose arms control the pivot-angle for steering. The Cyclone mid-motor now can focus on hauling me, whatever's in my saddlebags, or on the rear-rack--and of course the rest of the rear-frame. Sure, it maintains "positive pressure" to the box--but now, the rear-frame acts almost like a self-propelled one-wheeled trailer. I would assume this is a much more efficient use of its energy.

        While they're pulling, the front-wheels affect the Babboe Big's stability in another way too. Because both front-wheels are powered together, there's a sort of "caster" effect. Their symmetrical pulling-action tends to make the box want to go in a straight-line. This means when under power, the machine will have a tendency to resist its pilot's efforts to steer. It's not a super-strong effect, but it certainly is unmistakable. To be honest, when you're wanting to go in a straight-line, this caster-effect actually gives a very nice, sure-footed and stable feeling. The same applies when coming out of a turn--it's a downright delicious sensation--especially in light of how horrible it otherwise can be!

        Yet as with so many things, there's a negative-side to this caster-effect as well. When my motors are producing energy which I have to overcome, resist, or push-against with my arms--that energy is sort-of wasted energy--if you really think about it. It's energy getting taken up by my arms, instead of being taken out on the roadway! Whenever my machine is spending electrical energy to resist my physical operational inputs--it's wasting a little bit of my battery-power, and eating away a little of my range. I'm not going to cry about it, but this is one reason I remain interested in electronic differential as a function to enhance stability (a little more) and to increase efficiency.

        When compared to pre-assist, or even when compared to when it is powered by the Cyclone mid-motor system alone, it's as if I've a whole new machine--just as soon as those front wheels' motors are activated. I simply point the box in the direction I wish to go, and its motors take it there--relieving all the "pushing stress" from the Cyclone. The rear-frame follows obediently behind, while its Cyclone relieves all the "towing stress" from the front-motors. It is so sweet, when the front and rear systems are in balance... It's magic. Pure effin' magic!

        Because the front-wheels are essentially constantly working in a "climbing up and out" direction, the soft-surface handling is pretty magical now too. The box never digs in anymore. At the same time, that action of the front-wheels' motors applying more downward force to the rear-wheel; improves traction for the Cyclone system too--helping to keep it from spinning-out. Now, not all the beast's instability is gone; certainly not!

        The machine remains a backwards-facing tricycle. So, no matter how much praise I pour upon it, the thing remains inherently unstable in the corners. Too much speed coming into a corner, and the same inevitable and painful crash awaits the hapless Babboe Big pilot. When maneuvering in tight-quarters, and turning sharply, and accidental too-much-throttle burst from either system can also cause a scary launching-forward-tipping-over incident to happen. That's also not good. And I certainly cannot risk riding "along" banked surfaces either. The actual "tipping angle" isn't something I've measured, but the machine cannot take very much. I can go up or down a steep incline, but I have to keep the front-wheels pretty-much level to the horizon, if I don't want to tip over. Corners with negative-camber must naturally also be navigated at obnoxiously low speeds. Pythagoras--he keeps me on my toes. This tilted-roadway problem is obviously made worse by my taller seat-post--turning my tall-sitting self into lots of mass, placed high-up, and leaning in the unhelpful direction.

        Yes, many of the same old stability problems are ever-present, and lurking patiently, waiting for the chance to spring up and get me. To compensate, I use the simple strategy of entering corners easy, and then accelerating out of them--as you would in a front-wheel drive car. Naturally, if sight-distance or visibility, or traction, or other factors are involved, I just enter turns at a speed low enough that I'm sure I can safely stop within that sight-distance, in spite of the factors (defensive driving takes precedent always).

        And then, when it comes to stability--we've always got to think about stopping: Well, for stopping a Babboe Big, nothing beats a straight-line, with nice pavement. But then what about stopping in a curve? Braking with the front-wheels while turning, further shifts the weight of the bakfiets forward, and onto that same furthest-away front-wheel. Back to "what we don't want". Applying the front-wheels brakes in a curve is another sure-fire way to rapidly toss the machine onto its side.

        When taking a motorcycle rider training course a long time ago, they taught us two strategies for stopping on curves: One, was to brake while maintaining yourself along the curve; gradually straightening up out of your lean as you came to a stop. Since the Babboe Big doesn't lean (well, not in any kind of actually helpful way), this first method isn't going to work. The other stopping-on-a-curve technique, was to sort-of divide the turn up into a few straight-lines. You'd "square the handlebars" (putting the motorcycle in a straight-line path), then you'd brake hard, then you'd come off the brakes and turn a little further through the corner--then you'd "square the bars" again, braking hard, then turn some more, etc. until you're all the way stopped. I think the instructor said this method was good when you needed to get stopped very quickly on a curve, but was especially helpful whenever there's issues with the road-surface, traction, or stability--or... Maybe I remember that a little bit wrong--it was a long time ago.

        Anyways, that same second emergency-stopping-technique works with the Babboe Big bakfiets too. Square the handlebars, brake hard, turn enough to keep on the roadway, then square again, brake again, etc.

        [short excursion into dream-land]

        I think maybe an electronically controlled braking system could lend a degree of stability to this problem, but the system would have to work differently than ABS. Because the weight shifts so dramatically when turning, the front-wheel on the inside of the turn sometimes hasn't much weight on it at all, and will skid easily. A smart braking system could sense this, and use that as a signal to relieve braking pressure to both front-wheels, and to shift extra power to the rear-wheel's brake. Now, that might be unpleasant for the rider, who mashes his or her brakes, but only gets a wimpy slow-down out of the deal, but if it'd prevent a few tipping-over scares, it might be worth it. However, this is technology that (as far as I know) doesn't exist yet.Brake. Closest thing I've seen was the diverter valves on 1980's VW Rabbits. The rear-suspension had a linked trailing-arm design, and those valves would sense when the car's weight shifted forward, and relieve some rear-wheel brake pressure, to aid in skid prevention. Because the bakfiets has no suspension, nothing like that would work. It doesn't change shape when it tips--it just tips.

        [okay, I'm back now]

        All things considered, the advantages so far, seem to outweigh the costs. I'm looking forward to getting my parts, and getting the Tri-Motor 3WD system up and going again--this time with the disc-brakes.

        I'm not so much looking forward to unlacing and re-lacing those rims again though--so I hope this'll be the last time for a while... Hmmm... Then again, when I get my new motors, I think I'm going to take a look at them. If the covers are interchangeable (and it seems to me that they should be), I won't have to restring anything--just swap the covers with the fittings for the disc-brake for the covers with the fittings for the roller-brakes--and install the complete wheels. I can then put the other motors into rims at my leisure--and those motors will be brand-new inside, for the other two projects. I hope that works out. If there's a difference in the axle-shaft, then it probably won't work, but otherwise--we'll see, when the motors arrive, and not a second sooner!

        I am hoping, that even though the front-wheel motors have a lower efficiency-rating, and even though they're wasting a little energy resisting my arms' inputs sometimes--that when using the disc-brake versions, my range won't be too compromised. I do not know how much of the loss-of-range I experienced with the tri-motor configuration, was due to those roller-brakes dragging. In any case, if any drop in range remains limited, that's a plus. If not, I may just opt to purchase another battery--one I can rotate (dividing the cycles between the two batteries should make both last longer), and then when needed, I can take both batteries along--for extended cross-country trips.

        More to follow, I'm sure...

        Take care, everyone!

        Tklop
        Last edited by tklop; 10-03-2018, 03:28 PM.

        Comment


          #35
          Okay--going off into "dreamland" again here:

          The last potential gain: Differential.

          I'm thinking actually, that one day I may experiment (as I'd suggested) with a programmable, and "smart" dual-BLDC motor-controller.

          These are frequently used for robots, wheelchairs, or any number of things which have side-by-side wheels driven by separate motors.

          The ones I've seen at Uncle Ali's Place have lots of features, allow for various formats of control inputs and include an "electronic differential" effect.

          Since obviously differently configured robots would have different turning-radii, these type controllers must be able to be either programmed for, or to be able to "learn" a given vehicle's turning radius, in order to produce an useful "differential effect."

          If that assumption is true, then I think I may be able to make it work; and here's how I am imagining being able to control it:

          I think I would mount a joystick-type steering-control module onto the underside of the box. It would mount upside-down (and also rotated 180 degrees if installed aft of the axles) on the center-line, and pretty close to the pivot-point where the rear-frame bolts to the box's frame. I'd provide a way for the joystick's downward-dangling toggle to be engaged with the rear-frame--so that the joystick moved as the box is twisted left or right. I'd probably keep adjusting its position, until the full-deflection box-twist nearly caused the full-deflection of the joystick. In this way, I'm imagining I'd be able to use the joystick to sense the turning-angle of the box, relative to the rear-frame. I'd then send this signal to the left-right steering control inputs on the controller--telling it when, and how much electronic-differential-effect to apply. I'd also intend to continue to use the thumb-throttle for speed-control input.

          If I had "electronic differential" effect, I'd also like to be able to switch it off--synchronizing the front-wheels as they currently are--for off-road soft-surface use. I'm not sure how it would work out with the "electric differential". Sensing box-angle might already lessen the odds of wheel-spin, but when it's really soft (like in sand) the machine sometimes starts to "swim" a bit, and I think this may produce unwanted behavior from the controller--with electronic-differential actively working.

          This isn't currently an issue at all. When driving through soft sand, the current simple set-up, with its synchronous pulling-action of the front-wheels allows the machine to stay on course--toward wherever the box is pointed--no matter how much it is "swimming". Sometimes though, the rear-frame might drop into a groove, or "swim" out to one side or the other. In this instance, I do not want the bike to actually turn. The controller has no eyeballs, but I do. I may be keeping the box-end pointed steadily down my path the whole time--but if the controller thinks I'm turning, it'll want to increase the speed to the outside-wheel, decrease to the inside. It's in circumstances like this, where the bike's rear-frame begins to "crab" or side-slip relative to the box-angle, when I'm afraid the differential-effect which would be so helpful during on-road use, may become the enemy of the operator.

          When it comes to limited traction situations, I'm also in the dark as to what other benefits and liabilities might come with these controllers. I'm just not sure what these controllers can or can't do. Are they "smart" enough to be able to sense motor-speed, and use that data to offer traction-control--or even if in a more limited sense--simply to detect and compensate for wheel-spin? I've no idea. About a lot of it.

          Normal (non-limited-slip) type mechanical differential axles on a car, when encountering soft-surface or slippery conditions, can actually increase the chance of wheel-spin. Clearly, that's not what anyone needs in those moments. I'm pretty sure (someone correct me if I'm wrong here) that's also why four-wheel-drive vehicles employ a "differential lock"; it helps when it's hard to get traction.

          At any rate, based upon my experience so far, the bakfiets has driven right through everything I've attempted, and quite well--with the two motors controlled as they currently are (and zero differential-effect). This suggests to me, that this will probably remain the "mode" I prefer, when I need to navigate over soft-ground, sand, etc., and again--why I want to be able to also engage an "electronic differential-lock" (or just turn off the differential effect) as I wish.

          As a side-note, a controller like that would naturally also be capable of powering me in reverse. But a reverse-gear would only be available to me, if I bought different motors. It just isn't needed though, for a cargo-trike like this one. Once the rider hops off, the back-end of the bike can just lifted (by the back of the rear-rack), and walked around, until the machine is facing the other way. Basically, reverse might be a nicety, but not a necessity. No matter what my load, or how difficult the surface, I've never, ever needed any need help to get turned around.

          Though not in a position to afford a lot of expensive experimentation, I'm still on the quest to bring the absolute most out of my bakfiets--this being my goal from the start. I feel by introducing three-wheel-drive to the mix, I've already achieved more than I ever thought possible in terms of enhancing stability and offering greater versatility. As I see it now, that leaves only one large technical goal to be achieved: Finding the way to make my tri-motor system work in the most energy-efficient possible way. Electronic differential might be the answer, if I can find a way to achieve it.

          Among the issues and unknowns:

          1) Can any of these dual-BLDC motor-controllers work (or be programmed to work) with e-bike BLDC geared-hub motors? If so--can they also work with mine?
          2) Okay, these robot-controllers are "smart"--but how "smart" are they? Can they at least "learn" my turning-radius?
          3) How exactly shall I best set up the controls?
          4) What other useful features might I achieve? Traction-control? Tip-over sensing?

          Have I mentioned I'm not sure? I do not know if I'm going down the dual-controller rabbit-hole or not. But I must be honest with myself too. The way this whole project has gone so far, I have a feeling that if I get all the right answers as far as the parameters and compatibilities are concerned--I'm probably eventually going to give it a try.

          If I do, and the machine ends up riding like a dream, with all the same stability, but also feather-light non-operator-resistant controls (and I expect it would) I'll be sure to offer an update.

          I've seen robot controllers for four separate BLDC motors--I wonder if there's one for three? Surely there are three-wheeled robots in the world, some of which would need three BLDC motors to work together. Would their controllers be "smart" enough to be able to offer three-wheel electronic differential? (When turning a trike, all three wheels will be rotating at different rates).

          And, can these types of controllers handle different kinds of BLDC motors at the same time--on the same machine? Could one be set up to power my Cyclone 4KW mid-drive, as well as the hub-motors? I've no clue. Maybe so, but I have a feeling probably not. There's an awful lot I don't know.

          I'd welcome any feedback on my ideas / theories / dreams when it comes to this. It seems I'm venturing into some uncharted waters with this project. At least it feels that way, and has for some time now. I'd welcome any corrections, advice, feedback, or other relevant input. And encouragement is always welcome too!

          In sharing my developments here, I'm not only thinking of my own project. Like many others here, I hope the things I learn may be of benefit to others.

          I'm imagining there must be at least a few guys and gals out there with front-heavy trike-designs like mine, who would like more stability, and the ability to operate on softer surfaces. If sharing my experiences here helps unlock that potential for others, that's fantastic!

          Many cargo-bikes (though not with my own) are made with all three wheels on the trike the same size (26" is common). For trikes like that, maybe all three wheels could be equipped with matching-output geared-hub motors. This might really help simplify design. Even if run cheap-and-simple with their three separate stock controllers, three matching motors could easily be activated with one throttle-signal, and it'd made for a pretty wicked little machine without a lot of fuss...

          And now, I plunge off into the deep waters. Want to dream along with me?

          Picture this:

          I'm thinking three-wheel-drive super-duty cargo-trike that can go fast (relatively fast), and is balanced enough to slither through curves like a snake. Though the components would need to be really strong, developing a trike with that "carving" type front-wheel geometry would be a whole new level of incredible--if made all-wheel-drive! Of course, this "carving" mechanism also has to be able to be "locked" into a non-tilt mode--for safety's sake, when hauling heavy or top-heavy loads. But in "Pike's Peak" streamlined and screaming mode--"Carving" through the twists would be totally effin' unreal!

          With or without the option to "carve"--I imagine a flat-bed front-end-loading cargo-hauler e-trike. Maybe equip it with a fold-out ramp for loading or unloading rolling cargo. I'm picturing a low-slung super-strong cargo platform, set between the front-wheels. Maybe, this platform could be height-adjustable too (for higher ground-clearance--as an example), or even be equipped with a lift-mechanism, able to raise it all the way up to standard loading-dock heights. If this lift-mechanism were well-designed, the platform could even potentially be lowered all the way to the ground. Roll your cargo in and out without a ramp at all! Perhaps the cargo platform itself might be hollow on the inside--or perhaps it might be built in a couple layers--but I'm thinking it ought to be made like a sandwich--pretty-much solidly packed with batteries. When in the low-slung position, the weight would give extra stability whether loaded or unloaded. And clearly, you'd want lots of insane capacity for something which was meant for heavy use. I'm imagining personally, that you'd want no less capacity than a 120 mile range (at reasonable speeds, unloaded).

          A flat-bed design would also allow for almost limitless configurations. Bare-bones, the platform could be equipped with simple anchor-points for cargo-hauling. In that simple, open-flatbed state, you could use it to take your brand-new washing machine and dryer home from the appliance store. Or maybe haul the engine and transmission out of your buddy's 4 x 4 pickup truck across the valley to the machine shop for repairs--whatever. You could set it up like a "stake-side" truck, with interlocking removable sides to haul uneven loads (trip to the recycling center with a load of scrap-metal, say), or you could even develop lightweight drag-reducing fairings--for streamlining various configurations of rider and cargo.

          Perhaps you could rig up a removable folding (tent-material) convertible-top--to keep you out of the sun (or those rare Southern California rains). Maybe those anchor-points could also be used to mount a couple (or four) bucket-seats with five-point harnesses, so you can carry terrified passengers around at high-speeds; perhaps you might develop a bolt-on roll-bar, for more passenger safety on such adventures.

          Wouldn't it be a blast at any rate, to have such a crazy beast of a cargo-trike as your "Luna Cycle Shop Truck"? That would be fun as heck--even if it was only a "one-of-a-kind" experiment--built only for use by specially trained, qualified, tested and licensed Luna employees!

          Even in the simplest of design configurations, you could still strap an old couch to the platform, and offer strangers rides up and down your local So Cal beaches (where permissible) through the high soft dry sands. Now, if that kind of capability didn't drop some jaws and turn some heads--and attract a new customer or two--I don't know what would!

          So, what do you say? Come-on, fellas, go for it! Do a tri-motor trike! Maybe it's something to for this winter, when things slow down in the shop. Just piece together a simple prototype, and give it a whirl--even if you plan to later recycle the parts into something else more useful if it turns out you don't like it... But I'm pretty sure you'll like it!

          You good folks did an electric Big Wheels--I absolutely love that you built that gorgeous drifter! But after launching that little beauty, you can't tell me you guys are afraid of going down rabbit holes! ;-)

          Luna Cycle always hits the ball out of the park--is my point--so of course I'd love to see Luna Cycle's take on the concept of a tri-motor trike. No matter what they came up with, it would be amazing--whether they built a blistering-fast high-performance land-speed-record-setting e-monster recumbent-trike; whether they built a 3WD fat-tire beach-crawler (or another 3WD kid-hauler); or if they went with my suggestion for a mad-crazy cargo-trike "shop-truck". You know it would kick ass.

          Anyways...

          Take care everyone!

          Tklop
          Last edited by tklop; 09-20-2018, 01:25 PM. Reason: for clarity

          Comment


            #36
            Best. Phone-holder. Ever. I wanted to post this to that "stuff I wish I knew / products I wish I'd discovered sooner" thread--but I can't find it.

            Remember folks--my bike fell in a ditch thanks to a failed (and more expensive) phone-holder!

            This is the one I have now. I've used it for months--copies on each of my three bikes. It is hands-down, the best, sturdiest, most solid handlebar-mounted smart-phone holder I have ever found. After I bought the first--just to see--I immediately bought three more! (two are on the bakfiets, one is on the Brompton, and one is on the Batavus). It is all-metal, and uses no wimpy spring-mechanisms at all--which your expensive device can pop out of.

            GUB is the brand-name. The phone-holder can be found (among other places) at Uncle Ali's place here: https://www.aliexpress.com/item/Adju...27424c4dzOJaCD

            Hands-free is the law here, even for cyclists. While driving, or cycling, you are not allowed to have a mobile device in your hand. Not taking it in or out of a pocket, not ever--not even for one second. So, depending upon where you live, the law can provide another solid justification to have a decent hands-free mount on your handlebars.

            But for my e-bakfiets rides, my mobile-device is also the closest thing I've got to a "dashboard". (I don't have any other displays at all--thank goodness). I usually only log-in to my BMS's Android app. I use the Bluetooth "Locking Feature" to switch power off and on (at the BMS), which renders the bike immobile. So, to "unlock" the bike, I need to open the app. While riding, if I choose to leave the app open, it provides real-time monitoring of my current rate of speed, my estimated remaining available distance, battery and BMS temperatures, and amperage drawn. So, my "dashboard" functionality--is another good reason for a solid hands-free mount.

            When I'm going someplace new, it can also sometimes help to have some navigation help--and there's my smart-phone (with Google Maps or the like) solidly fixed to my handlebars--and ready to deliver.

            And, if I have the kids along, they like to listen to music--and yeah, my HTC One Life smart-phone provides that too.

            Honestly, I'm not someone bound to my phone. I don't feel compelled to check it all the time. I'm usually the only person in any given place without their "device" in their hands--on the train, at the doctor's waiting-room--you name it. Furthermore, since I don't have any friends, I don't get texts; and because I don't participate in social-media, there's none of that endless distraction either. My phone stays pretty quiet. But I do have kids, and I want their mother to always be able to reach me; and that's the biggest reason I carry it with me all the time.

            When taking it along for the non-e-bike rides (with either the Brompton or my Batavus), my wheel-hub dynamos will keep it charged--thanks to my B & M Luxos U headlights. When I'm using my own leg-power, I don't like pedaling the wrong-way. Backtracking stinks when it's not part of the plan. So again--I find it helpful for navigation. And sometimes also to check the weather-radar, In either case, a smart-phone with a dead battery won't help much.

            Anyway, it's good to have a handlebar mount that I know I can rely on--and this is the first I've ever found. Even the nice enclosed zip-up ones for motorcycles are extremely poor quality--I wasted plenty of my money on a couple of those too--before finding the GUB one.

            Take care, everyone!

            Tklop
            Last edited by tklop; 09-25-2018, 05:26 PM. Reason: for clarity

            Comment


              #37
              I now see I've kind of shot myself in the foot--by wanting to make the bakfiets 3WD. No more lighting simplicity and reliability--no more hub-dynamos! Yes, I've bought 12V lights and a transformer, but I haven't any work space--so I can't install them any time soon.

              So--yeah--I'm not too big to admit it. This is a written tantrum of sorts.

              It's too bad nobody makes a wheel-hub motor with an integrated 6VAC hub-dynamo--same kind used on millions of bikes' front wheels the world around.

              I want the best of both worlds, dammit!

              If that product existed, I'd buy it.

              Think of it--the advantages of a hub-motor, but no more stupid quests to find the right voltage bike lights--no more battery-powered glorified flashlights. Done with all that garbage! Shoot--there's hundreds and hundreds of lighting choices out there already for hub-dynamos--in all price ranges and styles...

              Even if it sounds like it, the following is absolutely not a product promotion. Call it a review if you want to--I'm only calling it my experience.

              As far as bike-lights go, I've been through a bunch. So far, I am most impressed by the lights made by the German brand, B & M. Their high-end models are phenomenal, truly--but with a price to make you stagger backward in dismay Things made outside China cost more--okay--but hello, sticker-shock! That said, my Luxos U headlights truly are amazing. I've one on the Brompton and one on my city-bike. They're really well-designed, putting the light on the road where you need it, instead of in others' faces. The best way to describe the level of illumination, would be to say at night, the light-field and intensity is bright enough to be able to see broken bits of glass on wet asphalt--while riding at speed--in time to avoid them--and again, without blinding anyone. If you ask me, that's a pretty good test-standard for any headlight that's going on a bicycle.

              The light has various modes; off obviously would be one option. But when switched on, it has a daytime-mode (with intense daytime running-lights for good visibility), which automatically switches to "night" mode via a sensor. When either "off" or in "daytime" modes, momentary activation of its "on" button causes a signal-flash to be produced. In night-mode, activating the button places the light in "high beam / intense-flood" mode. Another push of the button returns it to normal mode. The light comes with a "remote" button you can place where you like (I like it under my bell), to turn the lights on and off (or to activate/deactivate the high-beam / intense-flood mode, or for the "single-flash-signal") so you don't have to reach down to the light itself if you don't want to. There are also status lights to indicate what mode the headlight is in, as well as whether my tail light is functioning properly.

              The Luxos U model automatically adjusts the depth of the field of illumination. Lengthening it, stretching out in front of me in order to match my speed; and then the opposite--directing more intense light at close-range when I'm going slowly. The light's beam-pattern is designed so that as the bike is leaned, a more intense pool of light comes down onto the roadway, precisely into the path of my front-wheel. I never more have to "turn into darkness".

              When stopped for traffic lights, or to unlock the gate--whatever it may be, the headlight also continues to shine for about five minutes (due to a built-in capacitor circuit--no batteries). And as if all those features weren't already pretty good, it also has a USB outlet to charge whatever I like--thus the U in the name. I use B & M brand tail lights in conjunction--again, they stay on when stopped--but no batteries. And the ones I've got include B & M's "Brake Tech" feature which can sense the dynamo's speed, allowing the tail lights to provide a brake-light function.

              Now--with just a little-old dynamo added to the e-bike wheel-hub motors, all this would be available--totally independent of an e-bike's high-voltage electrical system. It'd all work just the same after crashes, the same after submersion in water, the same after e-bike system and/or electrical failures, the same when the e-bike's battery is completely dead. Even if you left the e-bike battery at home--you'd still have lights--still have the same safety level at hand.

              Wouldn't that be great? Or is it just me.

              Seems to me, as if the safety-factor alone would be good enough reason to offer this. Nowadays, a busted e-bike is as dark as the road it's ever-so-slowly rolling down (or more than likely--along). Odd none of the manufacturers have found that to be particularly concerning--in light of an already existing super-simple solution.

              Less importantly perhaps, but also worth considering, is that this would also be better for e-bike conversions. Almost all the bikes here have wheel-hub dynamos, so they'd all be able to keep their lights, same as ever. It might not be huge, but that'd still speed up conversions a little, and reduce the project costs a little bit as well.

              Well, I figure if I can imagine it--someone else can too--probably already has. So who knows, maybe it's already in the pipeline.

              If I had a mid-motor-only bike, I'd never bother with anything but hub-dynamo lighting.

              But boy--I'd sure as heck be interested in a hub-motor with that dynamo-feature.

              It's really too bad it doesn't exist yet!

              Take care, everybody!

              Tklop
              Last edited by tklop; 10-04-2018, 10:39 PM.

              Comment


                #38
                I rode back to the beach today, to see how the 3WD does on the nearly impossibly soft sands there.

                In order to be sure I didn't run out of battery, I rode quite miserly on my way there; pedaling along--enough to keep myself warm--for the +/-50 kilometers to Katwijk Aan Zee; and Katwijk Strand. On the way home I did some higher-speed stretches, but was able to balance my riding enough to make it home with a few kilometers' reserve.

                The beaches here are all dredged sand. Super-fine, super-soft, and not dense really at all--not even when wet. I figured this would be a hell of a challenge--and I was right.

                I headed down a ramp, and stopped for a moment--scoping out the path ahead. It was clear, that I'd be in a lot of deep soft dry sand for about thirty meters, before I got to the slightly damp sand, and another ten or so to the wet sands.

                I wasn't sure at all how it was or wasn't going to go, but I also wasn't going to go back home without trying...

                So--off the solid-ground I went...

                It took lots of throttle.

                It was slow-going.

                But I made it down to the water, and along the water for a while...

                The wheels sunk in much more deeply than they had on the horse-paths.

                The front wheels' hub motors were strong, and though digging-in, they kept steadily pulling the heavy box forward.

                I pretty-much had to keep both systems full-throttle, but things actually balanced out pretty well that way. Though turning a little faster than the sands passing beneath, none of the wheels ever "spun out'. I could've used much wider tires--and I've room for them up front--but not under my current fenders. I can't go any wider on my tail-end, the seat-stays are too narrow.

                Worth noting:

                I just went with everything "as-is"--I used the same settings for the trip, that I used at the beach. A baseline.

                I made no adjustment to soften my tire-pressures for the sand. That would've probably helped some.

                I've still got the Cyclone "turned down" too--limiting it to about 30A max.

                The front-wheels' controllers are also still "turned down" to try to limit abuse to my BMS (designed for 50A continuous). If they weren't turned-down, I bet their 10A controllers would've cooked! But if they had beefier controllers--they'd have been even more capable.

                Now--having said all that, as soft as it all was set--I still also triggered my "over-current protection" for the very first time on my BMS. I think that's triggered at 60A. Anyway, It's a handy feature--no harm, no foul. I just powered everything off, then briefly "locked" and "unlocked" the BMS--and was good to go again. But I also took that as a sign that there'd been enough "testing" for one day.

                For comparison's sake, (again--based on current setting), when I mash both throttles fully--with the Cyclone in its hardest gear, the BMS rarely spikes over 45A--in spite of that max-effort better-hang-onto-the-handlebars acceleration. It was working very hard at the beach.

                After that, I pointed the beast straight up the beach, and then--just trotting beside--to keep up--I did the same thing as before; full-throttled my way through the deep soft sands... But not having to haul a rider, the machine wasn't in threat of another over-current; and in no time I was back to solid-ground.

                Lessons learned:

                On the positive-side, this almost impossibly-configured machine--even as it is currently configured--can get into and out of unbelievably challenging conditions--if required. That is very reassuring.

                But if I really want to spend a while going up and down the beaches,

                1) I need to swap over to that 100A BMS
                2) I need to swap those wimpy front-motor controllers out

                I am sure wider tires up-front would make a huge difference in the sand, but it seems like everything wider is knobby--and for that I'd pay a huge price in rolling-resistance. I'd need new fenders to make anything bigger work. New fenders will be an eventual necessity--I'm not blind to how "crowded" they are right now. In front I could go wider with tires, but not axles. I've got basically the full 100mm bracket-width for the entire fender-well--a fully-inflated tire could be 9 centimeters wide (on a nice true wheel) and it would still fit. That would be crazy--yes. But it I had an eighteen-centimeter wide front-end footprint (wider with squish) I'd sure sink in a lot less! But I would not opt for wider rims. Sacrificing strength for wider rim-width would be a poor choice for my application.

                At the moment, I don't think there are a lot of street-pattern wide balloon-tires with any decent leak-protection; at least none that are any wider than the Super Moto-X's I've already got. I've got a while until my current tires wear out, so maybe by then there'll be more options.

                -------------------------------------------

                I still want hub-motors with built-in dynamos. I still strongly feel lighting should always be able to function--no matter the state of the e-bike's battery.

                For now, I've gone cheap-and-cheerful.

                Until I can get myself a decent work space, I've decided to just go with super-cheap interim DIY lighting.

                Simple, waterproof USB-powered adhesive light-strips. White underneath the box--forming a pool of warm white underneath, and a strip to outline each corner in front.

                On the rearward-facing corners of the box, I did the same, but first took a permanent marker and colored a the light-strips red. I positioned a third down the center of the rear-fender.

                If I ride at night, I can just bring a couple USB power-banks, and plug the suckers in. Charge them up when I get home.

                I can do better, and will--but for just a few dollars' investment, I'm plenty visible.

                More to follow

                Take care, everyone

                Tklop
                Last edited by tklop; 10-06-2018, 02:09 PM.

                Comment


                  #39
                  I think as time goes on, I'm wanting to delve further and further into some of the options out there.

                  I'm happy with my front-motors, but when they eventually wear out, I'm already thinking of the next iteration...

                  I've read a lot of the articles at electricbike.com. They helped me arrive at the choice for the Cyclone system. Invaluable information--absolutely invaluable! Thank you--all of you--very, very much...

                  But, I didn't really focus super-intensely on hub-motor articles at the time, because I had no plans for one.

                  I've seen hub-motor powered bakfiets models out there. They're not bad, but also not very strong.

                  Now though, I've found my (relatively wimpy) hub-motors, when combined with the Cyclone--can allow for (comparatively) blistering acceleration. It is not an exaggeration to say I need to hang on firmly--and I'm talking about 200+ kilograms combined with rider.

                  This has me considering other design options...

                  My whole idea from the start, was to have things modular--easily swapped to another Babboe Big non-powered frame, when mine finally rusts away.

                  But now that I have gone AWD, I'm wondering if a new approach to my choice of motors may be worth considering (for future replacements--I don't plan on trashing anything that ain't broken yet)...

                  I will re-read many articles, to help guide me--and then proceed to the posts those articles (and my requirements) seem to point to--just as Í did before to lead me to the Cyclone...

                  I'd love to be able to use direct-drive motors, but (if I remember correctly) they're maybe not so ideal for ultra-low-speed high-torque demands (traversing a stretch of soft sand for example--at approximately walking speed)... But am I totally off-base in thinking that way? And especially in the light of how much more efficient the power-distribution works with the three-wheel-drive system, perhaps they'd be able to give me greater efficiency--and despite not being perhaps ideally suited for monstrously heavy cargo bikes--if working as a trio--maybe they'd be just outstanding!?!

                  So....

                  I'm curious about that...

                  If I could use direct-drive motors, I don't know if could use regen--but I could certainly save a lot of brake-wear with electronic-braking anyway (which would be a huge advantage due to my weight). It would be quiet too--direct-drive motors are whisper-quiet... That would be nice.

                  Even if I left the rear-wheel powered by the Cyclone, the harmonics wouldn't always have to be buzzing through the rear-frame. Even now, I can always just go Front-Wheel Drive if I want to go into Stealth Mode (the geared-hub motors are comparatively quiet too)--and then just kick in the Cyclone for when I need rapid acceleration, or when plowing through the dunes, etc... As a matter of fact, I busted the drive-chain on the Cyclone, and just elected to use the front-two motors for a few days, simply pedaling along with the back-end on leg-power alone. The redundancy of having a three-motor system is so awesome--I even did a single-front-motor test today, and though asymmetrical, one single front-motor was still enough to pull my 200KG three-wheeler up a steep grade. Yes, the top-speed wasn't as high, but it accelerated steadily to about 28 kilometers per hour--going uphill. On level ground, just one motor was an annoyance, but very much manageable.

                  One thing I've noticed for certain, in all the various tests and arrangements--is that the Cyclone is a lot more efficient than the geared-hub motors are. I've also yet to try them with the heavier-duty (with many more mosfets) controllers. It is possible, that if the new controllers invest less of their electrical energy in working to make themselves hot, maybe that'll affect the efficiency numbers; lift them up a bit... But they'll never come close to the Cyclone.

                  My Cyclone 4KW motor is rated at 97.6% efficiency. That's the best Cyclone makes. I think it is probably due mostly to having more copper mass--being 34 mm longer than the 3KW version.

                  My front motors cannot even come close to that. I will need to dig into the articles, to see what there is to learn... What are the efficiency numbers like for DD hub drives?
                  I'd love direct-drive motors on the front-wheels, if their performance would be acceptable--almost more for the electronic braking, than for the power... Braking with this beast remains an issue (though I've yet to install the motors with the disc-brakes yet).

                  That's going to be another story. I'm familiar with the technology in aircraft and in cars; however disc-brakes on bikes---are a new thing for me.

                  I went with some pretty nice-looking TRP Spyre cable-actuated mechanical calipers. I hope they were a decent choice--but I did note that they squeeze from both sides--rather than "deflecting" the disc toward one stationary pad. I heard (and read here) that was important--don't be cheap; symmetrical was better. The description says they're compatible with mainstream Shimano brake-pads too--and compatibility is usually a good thing--so that sounded quite reasonable. I didn't want to have something "proprietary" and impossible to find (or afford) replacement parts... But I freely admit that I honestly haven't a clue about them yet. When I've done more than just stare and play with them, I'll feel more ready to offer an opinion. To me, they do look like they were well designed and manufactured, and they appear to be strong. And they look snazzy. I hope they're not junk!

                  But again--because I'm going for simple-to-swap and modular, I did think it best to remain with cable-actuation, rather than hydraulics (despite the many advantages of hydraulics, there'd also be the issue of somehow activating two brake-calipers with one brake-lever----and that's another battle for some other time).

                  I'm still not happy about my lighting situation--and there's a part of me that's also intrigued by the idea of seeing if I can somehow fit a hub-dynamo inside a wheel-hub motor--so I can have my way-more-efficient-than-off-the-battery lights again--enabling them once more to work just as well with the battery removed completely.

                  And yeah... It all sucks, because I have no place to work--literally no place at all. And now it's almost freezing in the bike-shed... That's good--for fewer mosquitoes... But it's bad for arthritic fingers on cold steel tools and parts! I know--cry me a river--right?

                  So, that has hindered my progress significantly, and prevented me from "prettying" stuff up...

                  I've also plans to repaint. I'm sick of the flames. I think I'm going to go with Fenway Park green--nobody will recognize it here, but it'd look great. When I want to be seen, that's what I've got lights for.

                  So... That...

                  And I've got an upcoming meeting with a guy at a bike-shop who wants to hire me (though I've never worked in a bike-shop before)... And I'm honestly stressed out about it. I'm uncertain of dealing with Dutch customers for one thing--and I also don't know everything about bikes--far from it! I only really know what I've learned working on my own bikes... If hired, I do not want to screw up too many times (though I'm realistic enough to know at least a few screw-ups are probably inevitable)... And for other reasons related to my disability, I"m not sure how well it's going to go...

                  So... That too...

                  Now--it I got that job, and if my boss would let me use the store's workshop (after hours maybe--once in a while)--that would sure help me get some things tidied up on the bakfiets...

                  But that is getting pretty far ahead of myself.

                  More to follow, I'm sure...
                  Last edited by tklop; 2 weeks ago.

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                    #40
                    Well, just like the first time I went through the various articles, it seems everything I had--opinion-wise--about direct-drive motors remains.

                    For my project, it's apparent that DD motors will never work. The braking benefits (especially if supporting regen) would've been the greatest advantage for me, but the motors are just too weak a design.

                    According to all the info I'm finding both in electricbike.com's articles, and according to others as well, direct-drive motors would just be totally inadequate for my project. direct-drive hub motors are not suitable for heavy, slow machines.

                    I knew I'd read that before, but was wanting to re-evaluate the articles, in light of what I've now learned about the way my bakfiets presently works.

                    But this time through the articles, I really can see the biggest obstacle: Heat. My bakfiets will fry even the very best of the direct-drive motors out there--and probably in just one ride. It is slow, and heavy, and would basically always be needing to work as though "climbing a hill". The articles' descriptions of the motors' weaknesses primarily had to do with poor heat dissipation--a universal direct-drive problem--only partially lessened by the use of aluminum motor-frames. The descriptions in the articles imply that they're woefully inefficient at low speeds, where they apparently are better at producing heat rather than torque--and where they're most vulnerable to the ever-present heat-buildup weakness.

                    Plowing and swimming my way through soft sand at near walking-speed, would not be kind to a direct-drive motor.

                    Punching holes in a DD motor to let water inside--in order to slightly postpone the still-inevitable overheating--is akin to putting on more deodorant, when you stink, instead of taking a badly-needed shower. Any motor which under normal operation will get so hot that it will destroy itself--is a failed design. If I were a retailer, I'd refuse to sell them myself; explaining to my suppliers their design mistake. "Go back to the drawing board, and try again."

                    The idea of venting the things isn't without merit, but it fails to recognize the basic realities: Bicycles aren't made to operate in gymnasiums. They're made to be used outdoors. Here on Planet Earth--it rains. So, all components used on outdoor-objects like bicycles--all their various bearings, all the lighting, motors, controllers, switches, throttles--all of it--should be made to withstand years of service on a jet-ski. If it's not made that well, it's a piece of garbage.

                    Now--my front-wheels' motors actually came with an IP rating (I'll look it up and update this with it)--but I think it was at least IP28 or something. I thought that was pretty decent, and their power-cables have nice waterproof connectors (aided with silicone grease). But show me a waterproof throttle--and I'll order ten of them tomorrow! ;-)

                    Oh, I know you're not listening, Luna--and that's okay. But I can dream here!

                    The way I see it, Luna Cycle is a pretty major retailer, and as such, you guys have discovered you've got the ability to leverage higher quality from suppliers. In fact, you guys brag about that fact in your store's listings--actually many times; and hell yes--you absolutely should brag! This allows Luna Cycle to deliver much better products to your customers. Between that fact, and the support you offer through this forum--well... You fellas at Luna Cycle are heroes in my book--seriously! Yet I wonder: Out there in Sunny SoCal--do you concern yourselves much with weatherproofing? How many of the components and battery-packs sold in your store can be ridden several miles through an intense thunderstorm, with wind-driven heavy drenching rains? How many of these components won't mind at all if they're mounted on a bicycle which is parked outdoors in the Seattle rains for sixteen days in a row? How many of the items you sell will work after being left outdoors during a Canadian ice-storm--after the half-inch of ice encrusting the entire bike thaws out? Yeah--I'm willing to bet the number is probably a big, fat ZERO! It would cost a fortune to fully weatherproof some things, and others are beyond your control (components like throttles and the like). But it seems to me, you should be asking yourselves these questions--because these are the real-world conditions e-bikes encounter every single day in the world. So--Luna Cycle should also work on weatherproofing. First of course, for those items you folks assemble or manufacture yourselves--but then you should also use your market-leverage to try to demand weatherproof components from your suppliers. Tell them you've got exclusive customers that demand super-high quality... I dunno...

                    It may not rain much in SoCal nowadays--but it does in the rest of the world--and there's no telling what climate-change has in store for the future anyway. But the biggest point of all, is reliability here: When riding in rains that will make a rider wet right down to his or her heels--drenched--soaked through to the underpants--the bike beneath that rider had damn well better keep on working. How angry would you feel--if your system fried itself in the pouring rain--twenty-minutes deep into a forty-minute commute?

                    Questions to ask oneself as a retailer/distributor--include: Would you dare warranty your current selection products for use in all weather? And if not, how can you possibly justify that? Well, that's the real-world. That's the kind of conditions e-bikes need to be able to reliably perform in.

                    Consumers want better--and consumers like me would happily pay fair-market prices for real quality goods.

                    Anyone send me a link to the e-bike throttle designed well enough for long-term use on a jet-ski--and I'll buy it--even if it's eighty-five-bucks plus shipping. Just saying... And in fairness, my throttles are hanging in there fairly well--but I've also got an indoor parking place at home. When I start work the bike will be outside, all day, every day--whatever the weather...

                    And--I've got something most bikers don't have--I've got the wooden "Box"--so all three of my controllers, and almost all of my connections, can be safely tucked up in there out of the rain. Everything in the box is of course still subject to humidity--if the bike is parked outside--but the stuff inside at least stays out of the rain.

                    My e-bakfiets is my car. I ride it everywhere--and no matter what the weather. So, I do hope my throttles don't die a premature death on the handlebars. I've got a couple of spares, but yeah--not really the point.

                    So...

                    Sigh. Disappointment. No direct-drives for me. They're just too weak a design for my purposes. Even taking the suggested extreme measures to modify their failed design to allow for slight improvements in cooling--will be inadequate to make them effective for my bike. They'll still just overheat and burn up. Still, I guess it's good to have clarified that for myself!

                    It's the lure of that idea of regenerative braking that keeps making me want to go there. Darn. The efficiency that could offer me, even in this flatter-than-a-pancake place--would be a big plus... Dag blast it! Oh, well.

                    As I continue to gain experience with the bakfiets' handling, and become more accustomed to the best timing and application of throttle inputs--it's becoming more and more an extension of me while I'm piloting it... Sometimes it's still a wrestling match, but less frequently... My car-replacement really is becoming more and more enjoyable to ride.

                    Even today... It was raining like cats and dogs--and I had a job-interview at my former LBS (I've since moved away--but it was indeed once my LBS). On the way home I got drenched, but the bike--in spite of non-Jet-Ski components--performed once again, flawlessly.

                    My latest settings-adjustment was to just go ahead and turn the Cyclone all the way down--as soft as it would go.

                    Now, even my 50A nominal 80A Peak Instantaneous BMS doesn't overload, even if I mash both throttles. It might peak at or near 60A for a split-second, but even if climbing a hill, the bakfiets will rapidly reach top speed, and then the current-load will drop sharply.

                    ...(Tim's train of thought jumps tracks)...

                    I hope I can find a place with a great huge undivided expanse of parking-lot ice this winter (I'd be too scared to try a pond). But I'd love to play around with "drifting" my 3WD bakfiets. If the weather cooperates, I know I shall not be able to resist! I found a muddy patch a couple weeks ago, and though small, I could tell it will be loads of fun. When all three wheels are spinning wildly, the fact there's a bend in the bike--will make it very fun! If I had any friends, I'd ask them to make a video to share on my YouTube channel... Maybe I can get a stranger to cooperate...

                    Anyways...
                    Last edited by tklop; 2 weeks ago.

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