Well, the title sums it up. There is an abundance of blog entries and forum threads mentioning an annoying creacking sound when pedaling. I ve noticed it on both bbs02 and tsdz2 kits. It can be very irritating, and make you hate pedalnig. While there might be other reasons involved, at least in my case, it s definitely due to some play between the bike BB shell and the motor shaft. Since the shaft has to slide into the BB, this is kind of a necessity, and no matter how hard you tighten the shaft nut to the BB it will always slide a little bit when applying pedal pressure. So I d like to start a thead dedicated to fixing this issue. The problem is how to clamp the motor shaft hard enough so it won t slide even when you are standing on the pedals, without ruining the BB. I ve been on the look for a removable filler, like thermoformable plastic, or metallic glue, and had litle success so far. So what would you guys recommend?
Definite guide to suppress BB creacking noise with mid drive kits
- Thread starter qwerkus
- Start date
Rassy
1 MW
Good idea for a thread. I've had a BBS02 on my tadpole trike for over 4 years and over 3000 miles. Recently it started making that creaking noise you described and of course I ignored it for a while. The torque arm had loosened a bit and the BB nut had loosened. After fixing it all, including making the torque arm mounting better, the "pedal creak" has lessoned, but not gone away.
In my case, I think the original fit was very tight, so there was no noise. However, the frame of my trike is alloy and the bottom bracket wore a bit when everything was loose.
Since I have probably damaged the bottom bracket I'm thinking of using a small amount of JB weld on each end. If I experiment with the drying time, I might be able to pull the BBS02 out when the JB weld has barely set up, let it finish hardening, and then reassemble everything. An alternate plan would be to lubricate the BBS02 so the JB weld would only stick to the bottom bracket threads. Or maybe just grease the inside of the BB shell.
In my case, the BB is part of the tadpole boom and I think I could just purchase a new boom if I ever wanted to permanently remove the BBS02.
Still thinking about this, and will come back here and update my results if I ever do anything to "fix" it.
Edit: I've not noticed any "creaking" on my delta trike, which also has an aluminum frame. The BBS02 is positioned up firmly against the frame and doesn't depend on a torque arm to keep it in place.
In my case, I think the original fit was very tight, so there was no noise. However, the frame of my trike is alloy and the bottom bracket wore a bit when everything was loose.
Since I have probably damaged the bottom bracket I'm thinking of using a small amount of JB weld on each end. If I experiment with the drying time, I might be able to pull the BBS02 out when the JB weld has barely set up, let it finish hardening, and then reassemble everything. An alternate plan would be to lubricate the BBS02 so the JB weld would only stick to the bottom bracket threads. Or maybe just grease the inside of the BB shell.
In my case, the BB is part of the tadpole boom and I think I could just purchase a new boom if I ever wanted to permanently remove the BBS02.
Still thinking about this, and will come back here and update my results if I ever do anything to "fix" it.
Edit: I've not noticed any "creaking" on my delta trike, which also has an aluminum frame. The BBS02 is positioned up firmly against the frame and doesn't depend on a torque arm to keep it in place.
Found a decent workaround: aluminium foil!
Sadly I have no pictures of the process,but it's fairly easy: cut a 80mm (! not 68-70) long strip, roll it over the BBSxx spindle case - in my case I needed 2,5 turns, fold the 1cm protruding ending over the bearing, flatten everything as good as possible and insert it sloooooowly into the bikes BB. The BBSxx BB insert is slightly conical, so it will end up compressing the foil quite a bit. Since creaking noise only come from the drive side, this is exactly what's required. Took me a hour, and no more creaking noise. A nice side effect is that the multiple foil layer protect the BB shell threading should you want to remove the motor.
Sadly I have no pictures of the process,but it's fairly easy: cut a 80mm (! not 68-70) long strip, roll it over the BBSxx spindle case - in my case I needed 2,5 turns, fold the 1cm protruding ending over the bearing, flatten everything as good as possible and insert it sloooooowly into the bikes BB. The BBSxx BB insert is slightly conical, so it will end up compressing the foil quite a bit. Since creaking noise only come from the drive side, this is exactly what's required. Took me a hour, and no more creaking noise. A nice side effect is that the multiple foil layer protect the BB shell threading should you want to remove the motor.
Another option would be to pull the drive out and drill and tap some holes in the bottom bracket and install set screws. Tighten the set screws after reinstalling the drive. Loctite on everything.
fechter said:
I thought of this one, but I'm afraid you'd need fairly large bolts (like 2x M8) to reach a meaningful clamping force. Not sure about BB shell integrity with such large holes. I'd also worry about bending the spindle case resulting in bearing misalignment and premature failure. The torque pushing/pulling on this spindle is quit insane. Best way to solve this issue would probably be bafang making the spindle casing 0.1mm larger, but this would make installation in steel frame more difficult.
I guess it depends on how much play you need to fix.
Something like epoxy would work but you would have a really hard time removing the motor if needed.
Another possible option would be some cone washers at either end that will wedge into the ends of the BB. Something that resembles the plastic washers used on sink drains, only metal. The washer would probably need to have a slot so it can tighten onto the drive. At least this would be easy to remove.
Something like epoxy would work but you would have a really hard time removing the motor if needed.
Another possible option would be some cone washers at either end that will wedge into the ends of the BB. Something that resembles the plastic washers used on sink drains, only metal. The washer would probably need to have a slot so it can tighten onto the drive. At least this would be easy to remove.
Deafcat
100 W
qwerkus said:
This will basically not work, due to the thin wall and well below the minimum number of threads required for a reliable set screw hold (6-8 threads of engagement!)
The aluminum foil trick is the best so far, but it could also be steel or brass shim, or even paper. Whichever is used, I would also coat the shim with grease, to keep water out and to reduce friction, which both allows a tighter shim to be fit, and to prevent any wear from movement and cut down on any chance of creaking noise.
The big advantage of a shim technique, is that you can change the thickness by choice of material and number of wraps. I have used this same technique in many bikes, cars, and heavy machines, it's very reliable and effective (and a very old trick as it turns out... I've found paper shims in old machines that were probably a hundred years old, still intact and legible old pages, translucent from oil absorbsion).
onemorejoltwarden
100 W
A few threads on this.
My BBSHD has pedal creak that has groan (sorry)
and I was reviewing them before teardown to shim and grease .
? Any feedback on whether the AL or paper shims have held up?
Epoxy sounds like it could add to problems
See:
Creaking bottom bracket: anti-seize? (Finish Line green oil + Tri-flow soak)
BBSHD creaking noises under load (Shims BB)
BBSHD - Creaking Sound (epoxy BB)
and this one.
Also crank arm and crankwheel bolt as possible source
among other myriad potential spots.
My BBSHD has pedal creak that has groan (sorry)
and I was reviewing them before teardown to shim and grease .
? Any feedback on whether the AL or paper shims have held up?
Epoxy sounds like it could add to problems
See:
Creaking bottom bracket: anti-seize? (Finish Line green oil + Tri-flow soak)
BBSHD creaking noises under load (Shims BB)
BBSHD - Creaking Sound (epoxy BB)
and this one.
Also crank arm and crankwheel bolt as possible source
among other myriad potential spots.