Bafang BBSHD, 1000W, 68mm-120mm BB

not sure why you think a muddy trail is much harder on the drive train than winter road riding
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Experience!

I was never suggesting a different chain line. Please do not miss represent my suggestions.

The problem with many of the existing rings is they don't leave enough material to easily mount other sprocket choices. Easy fix if your machining the whole thing. The first ones with a spider that gives the correct chain line and a choice of many different material/ tooth counts will own this. The BBS still suffers from a limited range of smaller sprocket options for crawling along unless you go to a terrible chain line. No way too fix this with the current reduction case design.

Review of the HD is not as promising as I hoped. Will be interesting if they hold up to some hot rodding and if some controller mods are more possible.
 
You can't make a spider and preserve the chainline, 104BCD or 130BCD won't overlap the motor geometry.

Can anyone specify the 5 bolt BCD of the new drive? I believe it's different to the old ones.
 
Spent some time on Aliexpress site. Noticed few things.

First - 11.11 Sale next wednesday. The drive will be almost $100 cheaper.
Second - one of these monolithic chainring/chainguard combos. Just machine off the 5 "ears", drill something like 10-15 small holes to the chainguard part and mount it to homemade flat adapter plate?
Not bling or elegant, but hopefully functional offset chainring. And around 3-4 times cheaper than Bling Ring. Unfortunately just 45, 47 and 53T options available.
 
View attachment 1

What I would like to try is the bling ring up front at 42tooth. Then hack something like a 46 tooth front chanring onto the rear cassette somehow. Epoxy, rivets or what ever it takes but get the 46 tooth on the rear cassette and also get the benefit of the thin thick profiles of the race face rings working on both the front and rear. Having two large sprockets like this for hill climbing is what I want to do. Even if I make it a one speed with no derailer that tops out a 15-20 mph and a nice chain line I will be happy. I also think it may last for a long time. The trick will be to hack the 46 tooth front ring somehow onto the cassette. I figure its worth the effort and while a person is destroying the cassette in the process make it so you can space it in place on the freehub for a perfect chain line.
 
I did not know these large cassette sprockets were available so thanks for this Speedmd. Sounds like just what I will want.
 
The internal nylon reduction gear is officially confirmed?! :x
 
speedmd said:
Has anyone not overheating the BBS02 destroyed one of these gears? If not, the metal gears on the drive side is and has been the significant/ bigger problem.
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I think Karl made butter of one.
 
speedmd said:
Has anyone not overheating the BBS02 destroyed one of these gears? If not, the metal gears on the drive side is and has been the significant/ bigger problem.
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I ripped one to shreds early on. http://i244.photobucket.com/albums/gg23/phillyzj/Ebike/IMG_20150520_1840018_rewind_zpswlyvzty9.jpg

This was with 50-60 miles on it i think. I blame it on user error, i was running 25A and 60V and slammed the throttle on. Didn't fail immediately, waited until i was on my way to work 7.5 miles from home to go all the way...oops.
 
I've always wondered whether the nylon gear acts as a fuse. If overloaded, it will strip first without destroying the metal gears? Cheap and replaceable.
 
wompus said:
I ripped one to shreds early on. http://i244.photobucket.com/albums/gg23/phillyzj/Ebike/IMG_20150520_1840018_rewind_zpswlyvzty9.jpg
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Thanks for the info. That is actually a fairly artsy looking picture you took there. I was tempted to order the canvas print from photobucket, LOL. :lol:
 
Lurkin said:
I've always wondered whether the nylon gear acts as a fuse. If overloaded, it will strip first without destroying the metal gears? Cheap and replaceable.
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Not nearly as simple to replace as a fuse. I am classifying it as bad design - errr cheap shit design. There isn't much in the powertrain that is in need of protection from catastrophic/dire results to machine or human if it weren't to melt/break. If there was potential of say locking up the wheel and causing one to wreck or if it we were talking about motorcycles here and it somehow could cause the bike to throw the chain and destroy someone's leg and crack their engine block as sometimes happens on sportbikes, then I would buy that theory, but otherwise it is just cost cutting.

Quick story:
I developed a healthy respect for motorcycle chains about 10 years ago when riding with my buddy. He was on a zx9r and I was on a zx7r I had shoehorned a built 900 into. His chain snapped and was flung out the back of his bike and whizzed right past my head (I was following him - luckily in proper staggered lane position) while we were accelerating hard at about 60-70mph. His motor immediately started puking oil, but he kept it upright until he came to a stop. Yep, it cracked the case and messed up part of his tail fairing before making its way at me. We both considered ourselves lucky that day!
 
IMHO material is nylon because of silent operation. Mine has 3200km in 8 months and shows no sign of wear (using in steep wood uphils)

And that silence I enjoy a lot.. 8)
 
ginekolog said:
IMHO material is nylon because of silent operation. Mine has 3200km in 8 months and shows no sign of wear (using in steep wood uphils)

And that silence I enjoy a lot.. 8)
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Yes, I think the "nylon gear is an accident waiting to happen" argument is overused. If there were an appreciable number of failures, Bafang would change the material or suppliers would just stop selling the things as they'd lose money on all the returns, support and maintenance.

Yes, it can happen, but seems to be so rare as not to be worth thinking about.
 
The BBS system is already louder than DD hubmotors, what is a little bit more noise? Not worried about an accident, but I prefer reliability when climbing steep hills out in the woods which means I want stronger parts. This is something that would not be a fun trail-side fix. I have felt the 750W BBS02 case during longer rides and after long pulls it gets uncomfortably hot in my opinion. These things are still relatively new, but there is a growing number of people who are claiming problems at the 3-4k mile mark with their BBS systems.
 
Review did not specify if the nylon gears were much different if at all. Running these hot will soften them quite a bit also, so that should be considered for folks in warmer climates or running them hard. Still, we are talking a good increase in power and torque with the HD. Controller has been bumped to 30 amps and built with components that should be able to easily drive 40+ amps. I can see a few wrong program settings easily tearing up a borderline gear train unless it is way overbuilt. IMO a standard bike chain should be the weakest link or it is a design fail.
 
GNG? haha... I would avoid it too, unless you want to be fixing everything on it, except maybe the plastic gears. The 750W Bafang seems like a better deal; for superpower looks like Cyclone might be the better choice with all metal drivetrain... or just get something DD hub...

G.
 
how long does that gear take to swap out? even if you get 2k miles out of it, doesnt sound bad if its a cheap and quick swap. thats if you run it hard.
 
1KW said:
how long does that gear take to swap out? even if you get 2k miles out of it, doesnt sound bad if its a cheap and quick swap. thats if you run it hard.
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"The rotor is extremely difficult to remove, you must carefully pry it out using a screwdriver on either side at the same time in order to access the nylon primary reduction gear. This takes way more force than you think it should.
The 3 Phillips head screws that hold the cover plate of the nylon reduction gear are torqued down way too tight. I couldn’t get mine to loosen no matter how hard I pushed and turned. Recommend putting drive unit in a bench vise and pushing down with all your weight on a large screwdriver while turning the screwdriver with a pair of vise grips. These screws should be torx or even hex. Philips are the wrong screw for the job here. Replacing Nylon reduction gears is going to really suck.
Reassembling the axle into the freewheel was extremely difficult. You need to push it back together carefully while at the same time turning the axle to try to get the 3 catching teeth to fold down while pushing it together at the same time. It takes a lot of finesse and brute force will not cut it here."
 
1KW said:
how long does that gear take to swap out? even if you get 2k miles out of it, doesnt sound bad if its a cheap and quick swap. thats if you run it hard.
Click to expand...

The BBS02 was easier to replace the nylon gears, maybe 30 minutes. http://electric-fatbike.com/2015/08/24/replacing-a-peanut-buttered-nylon-primary-reduction-gear-on-the-bbs02/

The BBSHD is a bitch to get the rotor out and on the nylon cover plate I couldn't get the Philips screws to budge. You will likely need an impact wrench with a hammer to knock them loose. China should be banned from using phillips screws that are likely put on with impact tools.

https://www.youtube.com/watch?v=dMLHvEraXhQ&feature=youtu.be

At 30 amps it will probably be fine for most people. I'm gonna run mine with a 18fet lyen controller till something breaks. Because it will be fun to watch it burn.

I'd bet my favorite hamster that the nylon gear will be the first thing to go.

Karl
 
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