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  • tklop
    commented on 's reply
    From what I can gather, the following things seem to be true when it comes to regen--in bikes anyway:

    We've got two separate things gong on, "Regen" and "E-braking"

    From what I gather, regen--is binary; it's either on, or it's off--and on its own, regen doesn't provide much braking help--not much rotational resistance at all.

    And it's my understanding that electric braking forces don't help regen at all, but actually consume battery-power--reducing the effectiveness of regen with each progressively stronger setting.

    If those assumptions are correct, I believe I will be able to recover more energy than average, for a couple reasons:

    1) I have two-wheels working together. Logically, I'd assume that at any given rotational speed, I should be getting double the regen--with two wheels regen-ing--as opposed to only one.

    2) I have a lot more inertia to work with--which means I can brake earlier--increasing the length and duration of coasting/braking regen-periods. By taking longer to stop, I expect greater energy-recovery results.

    Now---if it turns out I'm wrong--and none of that matters at all, and I only get what most users are recovering--that is to say between 5% and 10% generally speaking--I'll still be totally happy with that.

    I've just got the feeling I'm gonna do a little better.
    Last edited by tklop; 18 hours ago.

  • tklop
    replied
    Got the DD hub-motors dropped off for building today. When they're done, I'll still need to swap controllers in order to make the install work. I might also need to swap to another type mechanical disc-brake-caliper (ain't much clearance on the wheel-side of the disc)... I'll have to see how tight it is--perhaps swapping the DD motors' screws for a style with a lower-profile head (round-head, or pan-head might work better) --if lucky, perhaps that might be enough... With every advancement comes new hurdles--naturally.

    DD motors will mean another slight improvement in terms of stability. They're heavier. More weight at the wheel-axles, shifts the center-of-mass lower (even if only slightly). Every little bit helps.

    I have tried to imagine ways for further lowering the center-of-mass. Perhaps I could do a floor-battery----that is, lay out say 72V and 200AH (or maybe more) worth of LiFePO4 cells--basically covering the plywood floor of the bakfiets--maybe one layer of cells, maybe two--then drop another plywood floor on top--turning it into a plywood-battery-sandwich. Wire it all together, with the BMS in my electronics-bay (under the bench). That'd be pretty awesome.

    Also: Speaking of batteries...

    Since repairing my 2nd suitcase-battery, I've been doing some various runs with it. It too has a Bluetooth interface, but doesn't display speed, or distance, or effieciency--or really anything all that terribly useful. It seems to be doing alright. I can punch both throttles, max-demands from all three systems, and there's no issues at all. The BMS isn't even getting hot. So--yeah... So far, so good.

    I need to really stretch it out one of these days--and see if I can determine what its effective range is (and calculate its "real" versus advertised capacity).

    More to follow--I'm sure.
    Last edited by tklop; 1 day ago.

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  • tklop
    commented on 's reply
    My DD's are 30H which should be less severe than your 45H's (I assume). And the rig is comparable to your trike--maybe a little heavier... But with two of them working together, I do expect the braking could be quite strong (though I doubt it'd be a linear comparison--when added together, that's 60H worth of magnets under my cargo box). I requested the motors for high torque, low top speed--maybe that'll also make the e-braking more severe.

    Fortunately, I've got nice heavy bar-stock type steel dropouts--about 1/4" thick steel. I'll get them locked down one way or another!

    I intend to delve into the programming. The controller's programming guide says that the "best regen" setting offers the least e-braking; and as the e-braking incrementally gets stronger, the regen becomes less and less effective. This at least seems to imply, that some sort of double-compromise should be attainable--selecting perhaps the second or third best regen-setting, while being sure I've adequate braking (the discs can take up the task for emergency stops). If the braking isn't too severe, I don't expect it'll cause much overheating either.

    I've found that even with the 350W (which are actually 750W) geared-hub motors---when I've got two motors pulling together, they deliver a heck of a lot of power. I'm hoping at least--that by teaming the front-wheels up, the e-braking force will be similarly enhanced; allowing me to select a fairly soft e-braking setting, and hopefully leaving a semi-decent amount of regen effectiveness. My plan also, is to adjust my riding style--to lengthen my stopping distances; hopefully turning as much of my intertia into regen as possible. I'm eager to experiment.

    If budget constraints allow--I'm going to drop the motors off at the wheel-builder. (short tangent) Being in The Netherlands is pretty awesome. I've got a shop just across town, does nothing but build bicycle wheels... Next-day delivery or pick-up. How cool is that? This place is about as bike-friendly as any place could ever be! You can bring in your own hub, even your own rim--or order from their extensive in-stock warehouse. And--it's so cheap, that I see zero reason to attempt to build my own wheels ever again. Awesome!
    Last edited by tklop; 4 days ago.

  • calfee20
    commented on 's reply
    My trike and my bike have the same 18 fett controller but the trike has a 35mm stator and the bike a 45mm stator. The windings are also slightly different to with the 45mm having a winding for a little more torque. Anyway the 45mm motor has an insane amount of regen "braking" it was almost like slamming on the brakes. I had to go into the programming and tone it down. Both bikes are about 100 pounds, 45 kilos. That will be 350# with me on it.

  • tklop
    commented on 's reply
    I'll see how they do with the stock controllers (KT48ZWSRK-TY01C is the model, rated 22A continuous, 45A peak). What info I can find lists them as sine-wave, but I'll just have to try them out. If they're awfully loud, then a controller upgrade isn't out of the question.

    I'm intrigued to see how they work out too--with regen... I suspect that when it comes to regen, my added intertia (because my machine is so heavy) may mean I get a lot more value from regen than most bikes (which would be featherlight in comparison). If that proves true, and regen proves successful, I may eventually set up a trailer with DD's--using them exclusively for regen and braking. If inertia is my freind--when it comes to regen--then a regen-trailer might actually work quite well--when loaded down (it would obviously be frightfully dangerous to power a trailer).

    Crazy stuff I think about...

    Soon I'll get those wheels built, then give it a try--and then I'll start to get some answers. Speculation is fun--but I want to get to testing!
    Last edited by tklop; 4 days ago.

  • calfee20
    commented on 's reply
    They are very quiet especially if you use a sinewave controller.

  • tklop
    replied
    Originally posted by calfee20 View Post
    I have a KMX trike that has 20 inch front wheels. I put a set of Super-motos on it and they are great. You don't need that much pressure either 35-40 psi should be fine.
    I've dropped that PSI--and have ridden for a while that way now. Yep. Better. Much better. Thank you!

    October didn't end up being DD month. Maybe November.

    I hope they're quieter.

    The banshee-wail of the geared-hub motors is a bit much. I love their performance! But the noise sometimes startles the hell out of people--other times clearly annoys.

    I hope they're quieter.

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  • tklop
    replied
    A quick note:

    Two more e-bike conversions launched into the world... Both belong to my ex...

    First, a 28-inch wheeled Batavus Yakima--which isn't gonna last a lot longer (due to corrosion mostly). It's a 48V system, with a 15AH LiFePO4 rack-battery, powering a 350W Suring front-wheel hub-motor, with KT-LCD3 display, throttle, and PAS. That's my ex's daily-commuter bike. I wanted to do a TSDZ2 mid-drive, but the bike is in too poor condition for that. When it dies, I can swap the front-wheel hub-motor to her next bike, or convert that next one to a TSDZ2--whatever works out.

    Second, a Giant Mio -- Mamafiets (Mamma-bike). That one is another 48V system--this time with regular Lithium Ion 18650 cells in a fish-battery, powering a 750W TSDZ2 mid-drive. Barely fits. The nature of the frame, means the motor really can't swing forward and up--and in fact, there's no room whatsoever for the rear-support bracket. I've got everything tightened down, and if needed, I can always manufacture a new bracket, or even potentially machine down the existing one until I can make it fit, but for now--I'll just see how it goes.

    More notes may follow on these two builds.

    That makes a total of five bikes I've now made electric (though the thee-wheel-drive bakfiets should almost count as three separate conversions--I've still only counted it as one).

    I'm not a pro at this--and I don't want to be. But I generally satisfied with my results so far.

    Leave a comment:


  • calfee20
    commented on 's reply
    Don't go that far.

  • tklop
    commented on 's reply
    I think the weight-distribution / center-of-gravity data might be interesting to see. The most useful data would be "including rider" --and then perhaps "rider plus cargo" (various configurations, if applicable).

    I'm imagining it might be hard to read the scales when seated. If you leaned and twisted in order to see the dial, you'd affect the readings. Perhaps another human would make that a lot easier... Telescoping mirror maybe--but then the readout would be backwards... Surmountable challenges.

    You could also take weight-measurments with the trike parked along a slope to simulate the weight-distribution while cornering (and if you were really good at math, you could likely extrapolate--though I'd not know where to begin).

    Maybe you're right. Maybe the information would be ultimately impractical, or useless... But yeah--curiosity sometimes demands answers anyway!

    Now I'm going to have to go buy a bathroom-scale myself!

  • calfee20
    commented on 's reply
    You have me thinking now. Maybe I should put a bathroom scale under my tires and see what the weight distribution is. I don't know maybe just more useless information.

  • tklop
    commented on 's reply
    That is a very handsome machine!

    Listen--I'm with you. I love the Super Moto-X's at lower pressures. At 45psi, on my Ryde Andra 40 rims there's nice cushioning, and the control remains crisp and swim-free. They really do ride like a dream at 45 psi. I remember reading your description and initial-review of the tire--which pretty much echoed my own opinion and experience with them. Just like with the Big Ben's, there is still some mild street-noise/vibration, but it's also that texture that lets them work on all kinds of surfaces so well. And my bakfiets, with its powered front-wheels gets just delicious grip with the Super Moto-X's!

    I only mentioned keeping my eyes open--in case new stuff comes along--but I can also say, unequivically, that the Super Moto X's are by far the best tires I've chosen for my project--to date!

    Maybe it's just because my machine is heavier... I'm pretty sure it has a narrower wheel-base than your KMX too... Maybe the geometry, and weight-distribution play a role in how it all behaves--that would make sense to me. But at 45psi, not long after I first installed them (some time last year I think), I had one bottom-out on a pot hole, and it dinged my rim.

    After that, I decided to keep them pumped up to 55psi--and though I've hit more potholes (and a couple curb-cuts too) I've not had any more dinged-rim issues. But riding empty, it's not as nice as it once was at 45 psi.

    If I put an extra load in the box, the tires "squish down" giving me more like that 45 psi-style shock-absorption again (and loaded--the risk of bottoming-out obviously returns). If very heavily-loaded, I won't even mind going up to the max-rating 65 psi--and can enjoy that same stability and shock-absorption--whereas riding heavily-loaded at lower-pressures, it's "swim-city" for sure.

    Due to its heaviness, and the fact that it's a cargo-hauling box-bike, I've felt keeping a bit of extra pressure in there seems sensible--"ready for the next load" --so to speak.

    Now, I've also got to admit--that I'm not religious about tire-pressures. I only do a pre-ride "thumb-sqeeze" pressure-check most of the time. I might put a gauge on them and top them off back up to 55 psi maybe every month or so, but not any more often. So, it may very well be, that I'm riding them closer to 45 or 50 psi--a lot more frequently than I think I am!

    In my way of thinking, a little extra pressure--helps afford me the luxury of not having to be religious about tire-pressures--whereas if I kept them on the low-side, and paid them only cursory attention for a month--they might get too low--and I'd be back to dinging up my rims.

    But you've got me thinking. Perhaps I overcompensated--by going from 45 to 55 psi. I think I will try to drop 5psi--go with 50 for my next few rides--and see if that's still alright. Maybe another 5 psi after that--if all goes well!
    Last edited by tklop; 09-19-2019, 05:34 AM.

  • calfee20
    replied
    I have a KMX trike that has 20 inch front wheels. I put a set of Super-motos on it and they are great. You don't need that much pressure either 35-40 psi should be fine.

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  • tklop
    commented on 's reply
    Knowing that I'll have some extra room underneath my new fenders, I've been poking around to see if I can find any other tire-options for my machine.

    The bakfiets has no suspension, so obviously all the ride-cushioning has to come from its tires. For non-suspension bikes, balloon-tires are one decent way to tame the severity of the bumps. For my 20" front-rims, the Schwalbe Super Moto-X tires [erto 62-406] running at +/- 55psi are currently (as far as I can tell) the best option out there for my front-wheels. I haven't been able to find any other tires with equal (or greater) air-volume.

    The next-closest ones are in the family of high thread-per-inch high-pressure BMX Street/Ramp tires. Those tires typically lack any leak-protection, but are otherwise in many ways really great tires--depending on the application. I've used them on the bakfiets before--back when the machine was "me-powered" (non-electric). Street & Ramp tires are really awesome in terms of super-low rolling-resistance, and are excellent for on-asphalt grip... But without suspension, they're hard as rock, and feel as though you're riding on wooden wagon-wheels. At e-biking speeds, that's horribly jarring--and completely unacceptable. Eliminating those 20" Street/Ramp tires, from my list of viable options, leaves only a scant assortment of knobbies...

    As of this posting, I haven't yet been able to find any balloon tires broader than those Super Moto-X's; and I haven't found any "fat-tire" options whatsoever.

    Of course new products come along all the time, and I'll keep my eyes open. But for now, I'm sticking with my 20"x 2.4" 62-406 Super Moto-X's--at +/- 55 psi.
    Last edited by tklop; 09-15-2019, 12:22 AM.

  • tklop
    commented on 's reply
    I'm going to bookmark that controller.

    I like the BT.

    I've got a couple 40A Cyclone BT controllers... I'm not sure if I'll be able to get them to work or not, but if so--they'd offer me good performance and options... I'm not sure if I can pair one device with multiple Cyclone BT controllers... Maybe only one at a time. That wouldn't help with temp-monitoring of both--though it would at least allow for setup and configuration. I'd have the same questions about the controllers in your link...

    Since the motors are side-by-side, I could sort-of infer that the temp of one, is approximately the temp of the other--but to actually actively monitor both front-wheel motors, I'd need to be sure I can pair more than one controller simultaneously (monitoring maybe via split-screen apps--somehow--I dunno). Otherwise, I'd have to bring two Android devices along--one per controller--and that really wouldn't be ideal. Honestly, what sounds good about now--would be a dual temp-gauge--with needles on it--like for a multi-engine airplane. Maybe an idiot-light or a buzzer--for when either motor gets too hot...

    The price of the motors I've got was quite reasonable (about $130 each--before shipping anyway). Because it's not a huge investment, I guess I sort-of see this as a kind-of "proof-of-concept" thing.

    I know my DD motors are less than ideal--but that's also because all of the motors available for my dropouts are all of essentially the same less-than-ideal designs. They'll all be more prone to the very issues that temp-sensing, auto-shutoff etc. are meant to protect.

    I get that.

    Due to these inherent design-limitations, it seems as if I'm going to have to be fairly gentle with them most of the time, to prolong their service-life (with or without temp readouts).

    Though perhaps misguided, my hope--is that this generally gentle use, will also mean that the risk of overheating is reduced--if not eliminated.

    I know my bakfiets is a jumble of juxtapositions sometimes.

    It's very heavy--normally, unloaded probably about 200 kilograms (with rider and battery).

    But on the other hand, that weight is being propelled by three motors.

    With my 350W (750W) geared-hub motors, teamed up with the 4KW Cyclone (+/- 2500W at my voltage) --when I've got that 4KW working together--well... That amounts to what--1,333W per wheel? That's a lot. The performance can be quite exciting; hang-on-to-the-handlebars exciting... And that's not really even peaking-out those front-motors for more than a few seconds--before I'm at my (unimpressive) 34 kph top-speed. Would not more powerful motors experience less stress--when working to provide similar performance? And couldn't that lower-stress performance also be available--from those more-powerful motors--with less heat-buildup? I honestly don't really know... I guess I'll find out.

    I'm experimenting now, (still with the geared-hub motors) with some advanced settings--for slow-start and whatnot. Though I still woud not trust any other person at the controls, I do work to continue to "tame the beast" --though it remains quite powerful (the acceleration-curve isn't as steep, but at their peak the front-motors' displays still show each topping out briefly at 750W).

    If I'm using similar "detuned" settings--with two 1000W DD motors up there instead--with the same three-level slow-start; even with low PAS settings; I expect they'll give me a very nice level of performance. If in general use, each operates in the 50W to 350W range my geared-hub motors do--to maintain my unimpressive top-speed; and if on the way up to that speed the DD motors only occasionally peak at 750 to 1000W --for annoyances like blue-smoke belching two-stroke scooters that I need to pass in order to breathe; or for other acceleration emergencies--like lahar-escaping or dump-truck avoiding; ---well... My thinking, is that usually, I'll be pretty gentle. And if I'm only pushing them hard like that intermittently--only on occasion--well... That's just not a lot of "hot-rodding"--and so I hope I won't face a lot of issues with overheat.

    I intend to likewise experiment until I can find the lowest effective e-braking settings--to hopefully avoid a lot of braking heat buildup. If I'm anticipating my stops well, I'll still use almost no pad-material--and as long as I've full braking-strength available mechanically, that should minimize e-braking heat-stress.

    Now... Loaded heavily? Maybe that's another story. And if I do decide to take the bakfiets on those "for demonstration purposes only" beach-runs, well... In those cases, I'll have to watch things closely, or I'll seriously risk cooking these DD motors--and I totally understand that.

    I did get temperature-tolerance numbers from the motor's manufacturer too, so if I do find a way to add probes, I can make sound decisions off what the readout says. But even if I do cook them--I'm really not out a ton of money. Concept will still be proven, and I can then improve with the next iteration... Better to have done things right the first time... But still--next time, I want temp-sensors, and I want a "reverse-gear" function too (I can get temp-sensing on the standard controllers with the KT-LCD3 displays; or I can get my reverse-gear with the Cyclone controllers--but neither controllers have both).

    October... Will be Direct-Drive month! :D
    Last edited by tklop; 09-08-2019, 11:50 AM.
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