Singlespeed & Fixed Gear - stupid chainline/bb/crank question

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habitus
10-23-04, 02:45 AM
ok, first: i've searched our subforum and can't find a sufficient resolution to my problem. lots have helped, but i'm still confused.

i have dura-ace 7400 double road cranks and a shimano 112mm bb. when i mount the chainring on the inside of the spider, it's too close to the chainstay (the chainring doesn't hit the stay, but the chain will), and when i mount it on the outside of the spider, the chainline is something like 45mm (way too long, of course). sheldon says that for my cranks, a 112mm spindle length is a good match (http://sheldonbrown.com/bbsize.html#dura). but this is assumes a 43.5mm chainline, which is the average of the chainlines if there were two chainrings on the double crank.

so, generally, if you need a straight chainline with one chainring on a double road crank, will you need to look for a shorter spindle than what's recommended (or mount the chainring on the inside of the spider, assuming that you have enough room)?

anyone have (older) dura-ace road cranks?


techone
10-23-04, 04:17 AM
How would the chain hit the chainstay?

habitus
10-23-04, 08:51 AM
How would the chain hit the chainstay?

yeah...good question.



it wouldn't.

i'm not sure why i thought that.