Announcement

Collapse
No announcement yet.

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

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

  • AZguy
    replied
    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.

    Leave a comment:


  • Wozzy
    replied
    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.

    Leave a comment:


  • pure_mahem
    replied
    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

    Leave a comment:


  • AZguy
    replied
    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.

    Leave a comment:


  • Wozzy
    replied
    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.

    Leave a comment:


  • AZguy
    replied
    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.

    Leave a comment:


  • Wozzy
    replied
    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!

    Leave a comment:


  • AZguy
    commented on 's reply
    I can't speak for mighty mini chainring but I'd bet it's no better than the 130adapter - with my 197 I have a good chain line, not "optimal" but only a little short of it

    To be fair I shimmed mine with 1mm washers, presently on a 42t. that also works with 39t which is the smallest that's readily available - there are 38t but that may require removing a little material here and there on the adapter so it doesn't interfere with the chain - I dunno

  • pure_mahem
    replied
    Curious if the chain line using the mighty mini chain ring is any better on the 197?

    Leave a comment:


  • AZguy
    commented on 's reply
    I just bought a spare chain (same type of course) and add several links from it whenever I replace the chain

  • Wozzy
    replied
    More about the gearing on my build:

    The chainring I'm using is a Luna Mighty Mini 30 tooth.
    It only has 8mm offset so the chain line is pretty lousy.
    I does have gobs of torque however.
    Due to the poor chain line, it seems that when in the 2 lowest gears the chain will pull off the rear sprocket if I apply full throttle while pedaling.
    Using the provided spacer, the BBSHD is mounted as close to the chain stay as possible, with less than a millimeter of clearance to the gear housing.
    The provided spacer looked like a remnant from the bottom bracket wrench cutout, but It fit perfectly.

    So I'm still trying to find the optimum setup for gearing.
    II tried to install the 46 tooth Bafang sprocket but the original 112 link chain was too short.
    I have ordered a spare 126 link chain to keep as a spare, so I can use that to tryout the 46 tooth sprocket.
    That will give me a chance to see if the additional offset helps, and check how the bike will perform with a larger sprocket.
    Because of the BBSHD gear housing, it seems that 42 tooth is the smallest size chainring available with a decent amount of offset.
    Last edited by Wozzy; 08-27-2018, 06:42 AM.

    Leave a comment:


  • Wozzy
    replied
    Hi, Sorry I'm a little late here, but I just found this thread.
    I recently completed a very similar build.
    Motobecane 2018 Boris FS SRAM NX 1X11 Bluto.

    I have a 21 inch black frame.
    The motor is a Luna 1000W BBSHD (100mm) with 30 tooth chain ring.
    My battery is a Luna 52V Wolf Pack.

    I have had it working for about 3 weeks now, and am very pleased with this setup.
    The kIt went together quite easily, and all the needed parts and spacers were included.
    I did have to do some filing and grinding inside of the bottom bracket as there was some weld and tool marks protruding inside.
    I've put almost 300 km on it so far.
    It's a definite head turner and gets a lot of interest as E-Bikes are really not very popular around here yet.

    I'm a very large guy (6'4", 290#), [193cm, 134kg] and the performance if this E-bike is outstanding IMO.
    One thing is... I have a totally screwed up Left knee from an old motorcycle injury, so I replaced the Left crank arm with a short 102mm crank arm.

    This area is quite hilly but the bike has enough torque to climb anything so far both on and off road. whether I pedal or not.
    I'm a little disappointed in the range, as I'm getting only 17 to 20 miles on a charge, but again given the conditions noted above, I guess it's not too bad.

    I'm considering a larger chain ring, but I'll need to get a longer chain as the supplied 112 link KMC X-11 EPT chain is not long enough for anything much larger that 34 tooth

    Here are a few photos:
    (sorry for the image quality, but my camera has been acting wonky)

    Leave a comment:


  • RiderRalph
    replied
    Sorry I have been MIA for some time. Summer got in the way of my posting.

    I did finally get my order from Luna and have my build 95% done. Still need to optimize some things like moving throttle to left side, add gear shift sensor, add brake cutoff sensors, etc. Also, I have already come to terms with the fact that my build will likely always be at 95% b/c there will always be something more to add, tweak, etc. The further I get in my build the bigger my list of desired add-ons becomes.

    Anyway, the above posts were super helpful in influencing my order and build. Based on above, I purchased the 100mm BBSHD to fit on the 19 inch version of this frame. As mentioned, Luna provided a couple spacers (I think one was 3 mm and one was 4 mm). I used the 3 mm one but as already mentioned a 1 mm spacer would be perfect. When I get around to it, I will swap out the 3 mm spacer for a 1 mm one. I too had to due some work on the bottom bracket to get the BBSHD to slide in (I used a Dremel, WD-40 and some elbow grease). Also based on above, I went with the 40t 130mm bcd Chainring Adapter and it appears to be a near perfect fit. Since my frame is 19 inch, I had no battery fit concerns and decided to go with the 52V Luna Wolf (Samsung 30q 12ah).

    Also, I have a new problem impacting my ability to get further on my build: the bike is so much fund to ride that I tend to want to ride it now more than work on it.

    Thanks so much to all of you that posted above!

    Leave a comment:


  • AZguy
    replied
    I've got a 17" boris (197mm dropout) and a dolphin won't fit and shark will - barely so I think any of the water bottle batteries aren't going to fit on the downtube.

    Since I run dolphins and sharks I put a rack and dolphin mount on the back of the bike. People say ohhhh it's terrible to have that weight back there but it doesn't give me any grief whatsoever.

    YMMV

    Click image for larger version

Name:	boris_2258.2xcrp.jpg
Views:	525
Size:	1.31 MB
ID:	70214

    Leave a comment:


  • Thane
    replied
    Hey Spooky,

    How did your build turn out? Could you post some finished pics please? I'm particularly interested in what battery you went with and how you fit it on your bike because I bought a 15" Boris for my girlfriend and I'm having a helluva time trying to figure out what battery will fit.

    Thanks!

    Leave a comment:

Working...
X