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Hi there,
The standard length is 113mm for a 50mm chainline, so for the Speedhub's 54mm chainline would 121mm (113mm + 8mm with 4mm either side) be correct? I'd like to keep the outer ring position free to fit a chainguard.
Any insight welcome!
Cheers
Yes works fine - 121mm BB & 4mm ring in middle position
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When a square taper BB says for example 68/111 does that mean 68mm chainline and 111mm spacing?
Cheers snaps! That's one muddy looking bike. As it should be!!
1961Bikie - 68mm refers to the BB shell width ie. the width of the frame where the BB is installed and 111mm refers to the length of the BB axle itself.
Both hubs and cranks have chainlines i.e. once installed where they position the sprocket/chainring. The chain will run straight if these two measurements are equal. The length of the BB axle will influence the position of the crankarm and hence the chainline. Hope this makes sense?!!
My thorn uses a 113mm axle and runs the chainring in the outer position so your calculations make sense if you want to run it in the middle.
Thanks avdave2. That's reassuring, especially as I'm contemplating spending decent money on a BB and don't want to screw it up ordering the wrong length!