Fitting a BBS02/BBSHD to Trek Carbon Fibre Frame

[d8veh]

A friend has asked me to help him convert his Trek Top Fuel 9.9, which has a carbon fibre frame:
http://mountain-bikes.gearsuite.com/l/3154/2012-Trek-Top-Fuel-9-9-SSL

Hub-motors are out of the question because the rear axle is a through axle of some sort - no drop-outs. I was looking at mid-motors, which would still create some problems because it has a BB92 bottom bracket, though this friend has access to a machine shop, so we should be able to make some adapters. There's one thing that I can't find info on: What is the clearance between the motor part and the axle on a BBS02/HD? I need to know this because CF frames are quite thick around the BB, and it's made worse by having cables exiting in that vicinity.

Has anybody converted a similar bike in any way?

 

[leo99]

On the site of em3ev in the pictures it says 13mm for the bbshd
Here is the link http://em3ev.com/store/index.php?route=product/product&path=36&product_id=215

Leo

 

[d8veh]

Thanks for that info.

I decided to go ahead with this project to fit a BBSHD. I have one last question. Does the BBSHD only come in one length for 68mm and 73mm bottom brackets, or are there two different versions?

 

[nutnspecial]

Bafang now makes the newer BBSHD model available in a variety of sizes (6 to be exact) : 68, 73, 92, 100, 110, and 120 mm

https://www.empoweredcycles.com/blogs/news/101474694-bottom-bracket-standards

Just noticed when reading about the shells bbsxx are made for and compatible with, tho I'm not sure if everyone would be stocking all 6 sizes. But 68 can be used for 73 also, tho not visaversa I think.

 

[KINNINVIEKID]

The 68/73mm motor is the same one..you just tighten the nut an extra 5mm on a 68mm BB.

 

[33du]

I have installed 100mm version to 73mm frame with machined piece of "pipe", axle is 15mm longer on 100mm (175 vs 190) version than in 68/73 so not so big difference

 

[Lurkin]

Check your chain offset first... need to measure middle of the frame vs where it will end up in relation to the BBSHD. I have been trying to track down the thread, but there were a few people disappointed with the fitment of the 68/73mm kit in terms of where the chainring ends up.

Bafang haven't been 100% clear on it, but the kit for 68 and 73mm is the same (similar to the Gen 1 units but in reverse. The 68mm kit could be used for 73mm if one of the lockrings were dropped, again, in some 73mm instances, fitment isn't always ideal). Bafangs own website if listing the kits as if they were seperate units (as it does about, which is likely quoted from them) but no one has come forward with specific kits - they appear to be range applied if that makes sense.

I'll have another dig for the thread. I should really summarise it to the wiki anyway.

[EDIT] ...and there we have it. This is the discussion I had in mind: https://endless-sphere.com/forums/viewtopic.php?f=28&t=68110&hilit=68mm+bbshd&start=350#p1186056

Trek bikes are usually 73mm? Can you confirm this is the case?

 

[Audiophiliac]

Thanks for that info.

I decided to go ahead with this project to fit a BBSHD. I have one last question. Does the BBSHD only come in one length for 68mm and 73mm bottom brackets, or are there two different versions?

You might be interested in this - https://www.empoweredcycles.com/collections/8fun-bafang-bbs02-accessories/products/shimano-pf41-bb92-89-5-92mm-to-bsa-adaptor-for-bbshd

 

[d8veh]

Thanks guys. The project is finished now. There were a lot of hidden difficulties, but we managed to overcome them all. I'm very pleased with the results - a 25kg all-up weight with a 19Ah 52v battery. A build thread will follow.

 

[robocam]

Do you have a link to your build thread?

Thanks guys. The project is finished now. There were a lot of hidden difficulties, but we managed to overcome them all. I'm very pleased with the results - a 25kg all-up weight with a 19Ah 52v battery. A build thread will follow.