Announcement

Collapse
No announcement yet.

First Cargo Bike Build: advice welcome!

Collapse
X
  • Filter
  • Time
  • Show
Clear All
new posts

    First Cargo Bike Build: advice welcome!

    Hi everyone, first time poster here, thanks in advance for any comments or suggestions! Like most newbs on here, I’ve done a lot of research but the questions just keep coming!

    I am building an xtracycle free radical “long tail” conversion on an old favorite mountain bike that I hope to use for commuting and kid hauling. I am about to pull the trigger on Luna’s BBSHD mid drive kit with a 48v 17.5ah battery, UNLESS one of you has a better suggestion!

    My commute is about 22 miles each way, and I ride it regularly on my regular bike (human power). I am an avid cyclist and enjoy the commute, but recently I’ve needed to carry a lot more weight, hence the cargo bike conversion.
    I also have two kids that can fit on the “hooptie” child carrier kit, so I’m hoping to leave the car parked for errands and shopping, etc.

    I have lots of experience as a bike mechanic, but zero ebike experience. I do not care about top speed at all, what I really want is RANGE! We live at the west end of the John Wayne trail, a rails-to-trails project that crosses our entire state. My dream ride would be to take my cargo bike with camping gear and maybe a kid or two, ride up and over Snoqualmie pass (about 40 miles), campout, and then ride back down to my house, without charging the battery. I plan to ride the bike “unassisted” whenever possible in order to save juice.

    Am I looking at the right battery, or should I spring for the massive 23.5ah version? Any comments are super appreciated. Excited to join the community, you guys are very generous with the knowledge and I’ve already learned a ton!

    #2
    Hello, and welcome!

    I grew up in the Pacific Northwest--you have a lot to enjoy on your rides, that's for sure.

    I suggest you just get the biggest battery you can reasonably afford.

    Though completely unscientific, my suggestion--is to consider (pretty much as a bare-minimum) about 2/3 of your project's total cost--for the battery. If your kit costs you $1000 then you should be able to dish out $2000 for a satisfying battery.

    From your description, it sounds like you're planning on using the bike a lot. As a car-replacement. Your idea to keep things slower is wise, it'll make all your components last a lot longer--offering you the reliability you will want in a car-replacement.

    Personally, as far as range is concerned, I want my bike to be able to take me where I want to go, let me enjoy myself there, and take me back again.

    I do not expect to get crazy numbers of hours of riding out of my battery between charges. Though I could theoretically go four hours on a charge--I do not want to sit that long on the bike seat. Any rides that long, are bound to need a break in the middle.

    However, I certainly can get an entire full day's worth of activities in. I can ride a few towns over, to visit with my kids; I can take them on some e-bike adventures (I've got a bakfiets--Cyclone mid-drive, with a 48V 60AH battery), and I still have more than enough left "in the tank" to get back home again. Of course it depends on the speed I'm riding, wind-resistance, etc., but tor my own purposes, anything less than a 100 kilometer range would be insufficient.

    So, yeah. I will repeat myself: Get the biggest battery you can afford--you will not regret it.

    I have never EVER heard anyone complain that the battery they chose had just too much
    capacity--but the opposite is quite often a huge cause of heartburn!

    Best of luck with your project!

    Take care,

    Tklop
    Last edited by tklop; 1 week ago.

    Comment


      #3
      Originally posted by tklop View Post
      Hello, and welcome!

      I grew up in the Pacific Northwest--you have a lot to enjoy on your rides, that's for sure.

      I suggest you just get the biggest battery you can reasonably afford.

      Though completely unscientific, my suggestion--is to consider (pretty much as a bare-minimum) about 2/3 of your project's total cost--for the battery. If your kit costs you $1000 then you should be able to dish out $2000 for a satisfying battery.
      ...

      However, I certainly can get an entire full day's worth of activities in. I can ride a few towns over, to visit with my kids; I can take them on some e-bike adventures (I've got a bakfiets--Cyclone mid-drive, with a 48V 60AH battery)...

      Best of luck with your project!

      Take care,

      Tklop
      Excellent advice, thank you! WOW 60ah, that is some capacity. Your needs sound similar to mine, so it looks like I need to be looking at quite a bit more battery. Did you get that one from Luna, or another distributor? Thanks again.

      Comment


      • tklop
        tklop commented
        Editing a comment
        My battery came from another vendor. That's the main reason I bought "extra" capacity--well, basically all the capacity I could afford to--just in case the battery turned out to be less than advertised. However, I do believe I got what I paid for--and I'm grateful for every bit!

        My bike is very, very heavy. Yours, with kids and trailer and groceries or whatever-the-heck will also be very heavy. I've got the 2000W-4000W Cyclone mid-drive motor. I've got things "turned down" to make it gentler on my bike-parts, but the motor is a monster, and needs feeding. Of course the motor will only do 4000W at 72V--it's basically a 50A motor--so at 48V it'd be maxing out at +/- 2500W--and as I've said, I got it turned down from there. The motor is rated at over 98% efficiency, so it does quite well all things considered. But I knew I needed both a big motor, and a big battery to push my big heavy bike!

        I completely believe Luna, when they claim to have good batteries, with good quality cells, and decent BMS's; but I have not personally bought from them so cannot speak from my own experience.

        Still, yes. I do think you will want a lot more "oomph" than you were planning on.

        Perhaps, with the high-quality cells Luna Cycle uses, a pair of these (currently on sale) 48V 24AH batteries might get you close to where you want: https://lunacycle.com/triangle-48v-p...er-long-range/

        You have a couple things going in your favor: You're intending to use your bike for low-speed goals. That means lower wind-resistance, and MUCH improved range. Furthermore, you are prepared to "help" with your legs. The more you do so, the greater your range.

        I do not know your specific neighborhood, but I know the area generally, and it is indeed often hilly and demanding.

        I personally would consider purchasing two of those units, but only one charger--keep them both ready to go for longer trips (carry the 2nd one as luggage someplace), and then just alternate between the two, when using them stand-alone for shorter (or not so heavily loaded-down) runs.

        I'll be honest--if the taxes and import fees weren't going to kill me, I'd have ordered from Luna myself.

        But things being what they were, I took what is pretty much the only other option--AliExpress.

        If you order anything at all from AliExpress, make sure to contact the seller first, and get all the clarification and information you need ahead of time.

        Personally, I'm happy with my battery. I've yet to do any "testing" to determine its "actual" versus "advertised" capacity. I may one day do this, but honestly--I just figure I got my money's worth in terms of range--so I'm good. Naive? Probably. If one day I figure out it's only a 20AH battery--instead of 60AH--that'll be a bummer! But as heavy as my machine is, I just do not believe I was cheated on capacity.

        I do not work for Luna, nor do I sell batteries. I'm just another newbie who is beginning to enjoy his first project!

        But I do remain certain you will want LOTS of battery capacity--for what you are intending. Car-replacement--essentially.

        Wow. Long-winded. It is a well-established fault of mine. Sorry.

        Take care,

        Tklop
        Last edited by tklop; 1 week ago. Reason: for clarity

      #4
      Thanks a ton tklop! I didn’t think of buying two batteries, but that actually makes perfect sense. One will be fine for my commute, and two for that dream ride. Argh back to the Luna catalog!

      Comment


      • tklop
        tklop commented
        Editing a comment
        I am glad to hear you found my comments helpful!

        Even when we were kids, the darn juice boxes were always too small. Now we're all grown up, we can choose for the big one. I say, go for it!

        I think that the limiting factors when choosing a battery should come down probably to your personal budget constraints first; and then perhaps to weight considerations secondarily--but yeah. Not enough capacity? You got issues! Too much capacity? Well... Yeah... I still don't think that's actually possible!

        Capacity gets you further. Capacity also gives you the potential to unlock a lot more capability too.

        Having plenty available (I hesitate to refer to it as "extra") gives me options others wouldn't dream of wasting their precious battery-energy on. I've already got a 48V to 12V converter, which--whenever I get around to wiring it up--will allow me to power auto-accessories too--off my battery. That'll provide a 12 power-outlet, which will serve mostly to keep my phone charged underway. Because my phone serves as my "dashboard", that's going to be a very handy thing--that 12V circuit. I can also use that power outlet to keep my beverages cool--in a 12V super-high-efficiency igloo-type (not brand) cooler--for enjoyment in an hour and a half when I get to the beach! Anyways, I do plan to also wire up a horn, and turn-signals, and possibly some retro-looking modern-tech LED motorcycle headlights--one for each side--who knows? But if I hadn't a lot of capacity to work with, I'm not sure I'd have wanted to risk adding the extra drain.

        Having about two and a half kilowatt-hours of power available, I've also considered keeping my eyes open for a decent 48VDC to 120/240VAC inverter (preferably "marine" but then probably 2nd-hand--due to my budget) to power regular stuff--laptop, lights, portable fridge--whatever--for use when I'm camping. After all, many places will let you charge up your battery, or other electronic stuff at their Main Office (offering a small "donation" for the service sometimes helps grease the wheels of commerce), but a lot of places have no power available over at the tent-campsites themselves. A roughly 350W 220VAC solar set has also crossed my mind. In conjunction with that camping/inverter idea--it would double as a recharge option for when I'm "off the grid" altogether. Heck, with a wise assortment of spare parts, a good assemblage of gear (and especially with a solar-set for recharging), I'd take my bakfiets on a cross-country camping trip for sure!

        The madness never ends!

        Though I've set her up to be (relatively) slow (I cruise at just over 25KPH), the motor and battery really unlock the bakfiets' full potential. It was already built with all the sturdiness I need, and capacity space-wise; but adding the battery and motor combined to really round out the package.

        I guess that's the thing. When you're thinking "car replacement" you know you're going to be compromising on speed right away, as well as comfort and weather-protection--so it is natural to not want to make too many more big compromises. In my configuration, I can keep my passengers and all my stuff under cover, out of the rain/snow/sleet/hail all nice and dry--but the operator (me) is left out in the rain and wind.

        I want to be able to carry both my kids, and take them someplace an hour away (by bicycle-speed). I doubt I could make them sit in there any longer than that at a stretch anyway--but yeah. Taking them places--that's important to me.

        If I go to the store, I want to be able to haul six or seven bags of groceries home with me. Eight if I want to--or more. (I've done as many as ten--plus both kids--back when it was a pedal-powered bakfiets).

        I want to be able to haul inconvenient and heavy objects sometimes--dirty things too--gravel, shingles, sacks of concrete, dirt--whatever--and not have everything break on me.

        I want to be able to go camping--with about the same amount of crap I used to bring along when I went with my car.

        That--is I guess what I think of--when I think "car replacement".

        And that is also why I believe you will want all the battery you can afford.

        Anyway, I hope you find what meets your needs.

        And again, best of luck with you project!

        Take care,

        Tklop
        Last edited by tklop; 1 week ago. Reason: for further clarity

      #5
      Just re-read your replies, I am basically following in your footsteps! Love the 12vdc and even 110vac conversion ideas, I plan to do the same.

      i went a different direction with my motor than I had planned; I decided to go with a simple and reliable DD hub motor on the front of my bike. It’s a 9C 1000w motor, and I will start with a 50v 30ah battery and see where that gets me. Super excited to get the build going, thanks for the help!

      Comment


        #6
        I am glad to help--such help as I can offer.

        I am not the only one here, but yeah--if you look at my project thread, you'll see I've no shortage of other wild ideas.

        One of my latest, is to add power to the front-wheels of the bakfiets, with a couple of high-torque low-speed 48V 350W motors--so I'll end up with the option for Front Wheel Drive, Rear Wheel Drive, or All Wheel Drive. Soft-ground is typically a big obstacle for a front-heavy beast like mine, and one which I intend to eliminate in this way. I'm not sure how it'll all balance out just yet power-wise, but I'm hoping to run all three motors off the same throttle signal.

        Anyways, my new hub motors and controllers arrived today, but I've still got other stuff to collect before taking the plunge (new pair of 20 inch "Andra 40" rims, spokes, nipples, a new pair of tires, tubes, rim-tape and rubber liner, a couple buss bars to simplify electrical power distribution, circuit breakers, switches, and of course a whole bunch of terminals). Maybe in a couple weeks, I'll have that stuff (and whatever else) collected, and then I can get started assembling and testing.

        Feel free to follow in my footsteps--but be careful: If you follow too closely, no telling how far into madness I'll lead you!

        Take care,

        Tklop

        Comment

        Working...
        X