BBS01B chainline


Apr 7, 2009

Having talked to Andy at Whoosh, I'm going to take the plunge and buy one of these, I think. I have the eBike I showed you the other day and it's fab but I think I am asking a lot of it, it's too big and I think it's ugly.

Can you let me know what the chainline measurement of a BBS01B is? Andy said it's adjustable but I might rebuild the bike as a hub gear (I love 3 speeds!) and they are a bit precious about chainline. I measured the 26" back wheel in my shed and it is 44.5mm (SRAM Torpedo 3 speed with drum brake (which I may or may not use).


Finding my (electric) wheels
May 25, 2023

this will get you a nice template showing different offset sprocket options.
But that's an American site that only talks about the 750W BBS02 and gives a quite different answer (53mm with Bafang chainring) from the drawing courtesy of Whoosh above (50mm).

So is the BBS02 fatter by 3mm? Are the people who say that BBS01 and 02 are outwardly identical, plain wrong?

Then on a another American website ( I find a comparison chart that gives an even further out chainline for the BBS02 of 60.8mm when fitted with a third-party chainring intended to make it LESS far out!

Which of these two Yanks is right? They can't both be.

Confusion reigns - especially when Americans are involved!


Esteemed Pedelecer
Feb 12, 2023
Here’s a German spin on a chain line template. They have this one for the BBS01/02 and there is another that I used for the BBSHD.

I know the BBSHD template works because I have used it. I printed it off, cut it out and inserted it into my BB and it was spot on. My chain line was perfect with the standard Bafang chain wheel.

So the BBS01/02 template should be good as well.

If in doubt buy some spacers as said above.
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