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15" Motobecane Boris FS NX - 100 mm or 120 mm BBSHD? What size ring gear?

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    So here's a follow-up on my gearing.

    I followed the Park Tool video to adjust my rear derailleur.
    Now I am able to use all 11 gears.
    I think that the 30 tooth gear is just about right for me.
    I can go 27 MPH on flat road in 11th gear, but still have tons of hill climbing torque in 1st gear.
    No more slipping, or skipping noises... Yay!


      Good to hear you sorted it out - no reason you can't use all gears if your chainline is reasonable - 30t will be a torque monster more suitable for throttle instead of PAS. I'm not sure what your low gear is on the cassette but after a lot of playing around for pedaling use as long as the first gear has ~10% more teeth than the chainring it will be suitable for PAS climbing up the steepest stuff albeit it may take the full 1500W! E.g. with a 42t first gear a 39t chainring works well and with a 46t first gear and 42t chainring works well and if I go with only a 39t chainring feeding 46t it's a bit low for pedaling since the bike is moving too low to be stable. I can't pedal all that fast (only one leg) so you may find ~20% might work for you.


        I'm curious to know what kind of range others are getting from their batteries with a similar build bikes.
        I'm a little disappointed that I'm only getting around 18 Miles on a charge.
        I know everyone's situation is different, but I'm hoping to get a feel for what is normal.

        For my typical riding:
        I'm 295 lbs.
        I pedal a little, maybe 8 to 10% of the time, usually helping to go up hills.
        26" x 4.0" tires inflated to 12 PSI.
        30T chainring, and 11T to 42T 11 spd cassette
        Bafang BBSHD set to 1500 watt max
        Luna Wolfpack GA 14S4P battery pack 58.8V full to 42.0V at BMS cutoff (13.5Ah, 704Wh, 50A cont. rating)
        This area is hilly, but not mountainous.

        What real range are you getting?
        Also I notice 4 to 5V voltage drop (read out on Bafang display) at full power. Does that seem normal.

        Thanks in advance
        --Bob W.
        Last edited by Wozzy; 09-09-2018, 05:12 PM.


          Drop is reasonably normal although 4-5V is a bit more than I see. On old worn out 48V/11Ah packs even thrashing I'll get 20mi. That's not where there's a ton of climbs and I'd expect less then. I'm also considerably lighter weight. With twice my weight and lots of hills your not out-of-bounds.

          Getting my controller setup properly made huge differences in range so I'd start there. t pedal almost 99% of the time. That's not to say I'm contributing much, I just pedal for control and every now and then get raceface and push hard.

          There's also a learning curve in managing how your riding affects the battery.

          Anyway - how's the controller setup? It's darn near infinite the possibilities and you might consider tweaking...
          Last edited by AZguy; 09-09-2018, 02:51 PM.


            What terrain are you traveling on? is it pavement, hard pack, gravel, loose dirt etc....? If your on pavement or hard pack you may want to try increasing your tire pressure a bit. lower pressure is good for traction not so good for gas mileage so to speak. Your ride may be a little more bouncy but it should help a bit...worth looking at anyways
            2018 Motobecane Boris Fat Bike BBSHD Build


              I had a severe motorcycle accident when I was 16.
              That accident really screwed up my knee.
              My knee hasn't gotten much of a workout in the past few years.
              One of the main reasons that I built this e-bike, was to try and get back into shape and rehab my knee.
              As I gain strength and mobility, hopefully, I'll be able to increase my range.
              I have already seen major improvements.

              My Bafang BBSHD controller is setup factory stock. I have a programming cable on order.
              Any suggestions for settings to increase range?

              The terrain I'm typically riding is mostly pavement (85%), with some loose gravel/cinders (10%), and some hard packed dirt(5%).
              I probably should pump up my tires a little. I'll experiment with tire pressure this week.
              Last edited by Wozzy; 09-10-2018, 05:45 AM.


                I'm missing half a leg just a few inches below the knee and the lack of using the leg in general and the limited range of use was giving me problems and one of the greatest benefits I've gotten from the ebike is that it is now far better off. I pedal pretty much all the time but it's pretty obvious (just by the size difference between the legs) any power coming from me is coming from the good leg and the other is just along for the ride. The constant motion has been very good for it and I'm having a lot less issues.


                  To help with my bum knee, I have a full sized crank arm on the right side and a short 4 inch crank arm from a unicycle on the left.
                  It's funny to watch someone else try to ride the bike that isn't expecting it.


                  • AZguy
                    AZguy commented
                    Editing a comment
                    Hmmmm... magnet....

                    I wouldn't want to put anything like a metal plate on the outside of the shoe (click, click, click when walking) and a plate inside the shoe would likely be too far from the magnet on the pedal to do much good but I suppose I could tuck a magnet in my shoe..... but then again I suppose I'd be picking up anything ferrous when walking.... Not sure how to make it work from a practical standpoint...

                    The shorter crank would be pretty easy to try though... not much to that...

                  • Wozzy
                    Wozzy commented
                    Editing a comment
                    I got mine here:
                    These fit the BBSHD, but I guess only useful for the the left side without the chainring.
                    Last edited by Wozzy; 09-26-2018, 03:20 PM.

                  • AZguy
                    AZguy commented
                    Editing a comment
                    Those are small - they look..... cute =]

                    Thanks for the link - It's my left so I'm good like that...

                  I am the six........ errrrrr.... thousand dollar man? Well heck it all cost closer to six million dollar really.... obvious that when that show came out medical costs aren't what they are today =]


                  • AZguy
                    AZguy commented
                    Editing a comment
                    Haha... never did care for eating that stuff.... just made me "confused" for waaaaay too long... Other routes of administration (various forms of inhalation) the worst that can happens is maybe 20minutes of "confusion" and that ain't no big...

                    I had one or two of the "there I was thought I was gonna die" with the divers but those are best left for beer time =] A few on other sports too.

                    At least my ebike riding isn't terribly fast.... even 25mph feels too fast especially without protective gear. For good or ill I've developed excellent crashing skills from doing it since I can remember LOL... So far nearly all my spills are at a stop or close to zero speed because that expensive leg don't always end up where it should be. Had maybe two or three get-offs but according to GPS never faster than about 12mph although you still pick up a scrape and bruise or two at that speed...

                    Been saving up for a new leg next year... going for the best I can do without spending my meager retirement account for it... Likely ~$8K after insurance.... lighter, faster, stronger....

                  • xcnick
                    xcnick commented
                    Editing a comment
                    for eight grand it better be clipless too. and another thread we highjacked. Sorry dude.

                  • AZguy
                    AZguy commented
                    Editing a comment
                    Oh well

                    ̅ \_0_/ ̅

                  OK, Let's get this lame thread back on track ;-) pun intended.

                  I was lamenting the range on my bike earlier.
                  This past weekend I took my bike to the Delaware River Canal Towpath.
                  As you can imagine, it was very level. The surface was pea gravel or hard packed cinders.
                  I pumped up my 26" x 4.0" tires to 18 PSI.
                  I pedaled gently almost the whole time (High gear, PAS level 3 or 4 of 9) and tried to keep off the throttle.
                  The ride was 20.8 miles total, and I I used about 25% of my battery. (I started out at 58.2V and ended at 54.1V)

                  All in all this seems very reasonable to me.
                  I'm guessing my range issues for my normal local rides are due to all the hills and stop signs around here as well as my low tire pressure.
                  Once the tires wear out I'll probably replace them with something less aggressive as I'm not really doing much difficult trail riding.

                  I gotta say I'm really pleased overall with the setup of this E-Bike.
                  It's one of the funnest things I've owned in a long time, and the fact that I'm getting out and getting back in shape is great.

                  The icing on the cake would be to be able get a Luna Ludicrous Controller for my BBSHD.
                  Last edited by Wozzy; 09-25-2018, 08:02 AM.


                    I vote Ludi. Voting on build reports would be a great way to allocate Ludis. Battery sounds perfect. Even if you don't get stronger you will get skills to save. A goodie is to pedal with no assist at a stop light for a half crank or so before using any power. In theory you could drive the Ludi low enough to still get range, but human nature is such that an occasional blip of the throttle and you have undone all your hard work.


                      I went through the first set of disc brake pads in 350 miles.
                      Tonight I upgraded the front brakes to 203mm rotors and metalic pads.
                      I haven't been able to test it yet (RAIN!), but hopefully it'll give me more stopping power, and longer brake life.
                      I already have the hardware for the rear rotor, but I'll try just the front first for a while, for safety's sake.


                      • AZguy
                        AZguy commented
                        Editing a comment
                        I'm really hard on brakes but 350mi is way less than my worst case... make sure you have the caliper adjusted properly - 350mi seems like something is out of whack.......

                      FYI, So far the front & rear 203mm rotors and Metallic shoes are holding up well. The only problem is that they squeal sometimes. I've got about 650 miles n the bike now.


                        That's typical with metallic pads and one of the reasons most shops go for the faster wearing organic pads - better to wear out fast than to have the customer constantly complain about squealing. If it's any consolation mine don't squeal any more for the most part...


                          I updated my gearing. I had my jeans get caught in the chainring which broke a tooth on the chainring, and caused my rear derailleur to crash into the cassette, bending several of the aluminum gears. So I swapped out my Mighty-Mini 30t for a Mighty-Mini 36t, and replaced the SRAM PG-1130 11-42t cassette with a Suntour 11-46t with steel gears. I also had to get a longer chain. This setup is much better suited for me. I seems that it matches my cadence better for when I pedal, There's still plenty of torque at the low end, and it's topping out at 30 mph at the high end. So far I'm very pleased with this new configuration.
                          Last edited by Wozzy; 12-16-2018, 06:34 AM.