BBSO2 crank arms

tinasdude

Active Member
I am sorry if it has already been posted, but I did a search and could not find the info. What is the crank arm length of the BBSO2. I am short and they seem longer than my cheap fat bike.
 

chixter

New Member
Speaking of crank arm. Does anyone know if I can replace the factory crank arms with an aftermarket crank arm? While out on the trail the other day some soft sand divertid my line a bit further then I wanted and the right crank arm bump against a log. It was not a hard hit, but it bent the crank arm pretty good. I was able to take it to the shop and bend it back but now I'm thinking I should be putting higher quality crank arm on this unit. I don't see why that wouldn't be possible any ideas?
 

J.R.

Well-Known Member
Speaking of crank arm. Does anyone know if I can replace the factory crank arms with an aftermarket crank arm? While out on the trail the other day some soft sand divertid my line a bit further then I wanted and the right crank arm bump against a log. It was not a hard hit, but it bent the crank arm pretty good. I was able to take it to the shop and bend it back but now I'm thinking I should be putting higher quality crank arm on this unit. I don't see why that wouldn't be possible any ideas?
This thread may answer some questions http://electricbikereview.com/community/threads/can-i-use-my-own-crankset.1145/
 

chixter

New Member
Thanx JR. This thread does address the issue...the Bafang supplied crank arms do bend easily IMHO. I clipped that log at less than 10mph, a glancing bump really, and the crank arm bent almost 45 degrees. I'm going to look for suitable higher quality crank ARMS not a crank set with chain rings on it. My 42t Bling Ring is performing flawlessly. As long as the square taper and the internal threads match up, should be do-able. I've whacked crack arms on rocks much harder with my Shimano set without any deformity.
 

J.R.

Well-Known Member
Thanx JR. This thread does address the issue...the Bafang supplied crank arms do bend easily IMHO. I clipped that log at less than 10mph, a glancing bump really, and the crank arm bent almost 45 degrees. I'm going to look for suitable higher quality crank ARMS not a crank set with chain rings on it. My 42t Bling Ring is performing flawlessly. As long as the square taper and the internal threads match up, should be do-able. I've whacked crack arms on rocks much harder with my Shimano set without any deformity.
It does appear to be a weak point. The thread I note has many posts on changing the cranks, not only the chain ring. It also goes into the stock ones being weak. I remembered the bent cranks in that thread when I read your post and thought some of the posters there may be able to help.
 

chixter

New Member
The big problem here is trying to find a RH crank arm WITHOUT at least a spider fixed to it. I could just order spare crank arms from Bafang supplier and replace if one gets bent or broken...but I'd rather have an arm that can take a little bumping without bending like that. Trail biking, every now and then your gonna 1. fall 2. clip something. Another idea is to get a good quality alloy T6061 or better crank set and cut the spider off of the right side, or looking at the assembly close, I don't think a spider would even interfere with anything. I thing the Bafang engineers really didn't put thought into the crank arm design as they figured usage mostly for commuting or road/path riding, not crazy Americans riding single tracks through the woods.