BBSHD - Will it fit...?

[wirewolf]

Hey everyone


The last few weeks i've been browsing this forum and reading everything I could about hub motors, mid-drives,...
After some consideration, I decided go with the BBSHD on my 29" Merida Big Nine 500 2015 MTB ( bought it new and it's been standing in my garage for 4 years and has been ridden maybe 3 times...).

The problem I have is with the selection of the BB size...Maybe you guys can help me out?
I've read the following articles:

- https://electricbike-blog.com/2015/11/19/get-a-bigger-hammer-bbshdbbs02-installation-problems-fixes-for-non-standard-bb-intrusive-chainstays/
- https://electricbike.com/forum/forum/knowledge-base/motors-and-kits/bbshd/10736-how-to-order-the-right-bbsxx-kit


My BB is 73mm BSA threaded standard (so far so good);
After checking and measuring everything, I think my chainstay will get in the way of the geared hub. I need 68mm clearance for the hub to fit. To get that I need to place a 4/5 mm spacer. Which should leave me with 10 or 11mm of thread depending on the final spacer. (88mm shaft - 73mm BB - 4/5mm spacer = 10/11mm). I've attached some pictures if it might help?

I've read that going for the 100mm version would offset the chain to much so I would love to hear what your thoughts on this are?


Thanks!!

 

[wirewolf]

Little update

Just found a diagram from a EU seller claiming the clearance is 64mm instead of 68mm.
Just today, I read about people claiming a clearance of 62mm, 64mm & 68mm.

At this point I’m really lost on what the correct measurements are...

 

[Hyak]

Shim to fit the gear housing which is the 47x64 measurement. The gear housing has a rounded edge, so may not need the whole 64mm. You can then decide if the chainring fits and the chain line is right. You could go for a smaller ring that is offset to bring the chain line back in. Then look at the opposite crank arm. you could use an offset arm to center the cranks if it bothers you and you don't mind too large a q-factor.

 

[wirewolf]

Hey Hyak


Thanks for the reply.
Would you advise the 100mm shaft then instead of the 68mm?