[ÆX]

so here is the deal.

my dh i am designing is running a ss
setup to the hight pivot. i need to get
my chainring very close the the frame
by using a narrow 73x108 bb and single
speed cranks.

so what is the standard chainline
for single speed cranks? 49mm-5mm = 44mm?

i have a pair of fsa single speed cranks and from the
face that touches the isis bb sholder to the inner ring
is 3mm. is that normal? my mtb fsa are 8mm.

thanks alex

 

[BikeGeek]

Depends on the crank. My ENO measures 47.5mm from the bb shell center to the chainring when using the recommended 113mm spindle.

The chainline for the FSA V-Drive MegaExo Singlespeed Crankset is advertised as 50mm.

Sheldon Brown sheds a little light on the defacto standard. He mentions that "stock MTB triple cranks usually have the outer chainring at around 52-57 mm; the middle is normally 47.5-50 mm." Since you ideally want to run the chain as inboard as you can, and the chainstays on most frames rule out the inner ring position, most use the middle ring position and industry has run with it.