Classic & Vintage - Can an 8 speed crankset be used to replace a 6 speed?

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Sincitycycler
09-13-06, 08:11 PM
I have an 1987 Schwinn Letour with a Sugino 52/40 crankset with 170mm arms.

The drive train is a 6 speed.

Can I substitute a 90s Dura -ace 8 speed crankset for this? Thanks

Tequila Joe
09-13-06, 08:42 PM
Most 5, 6, 7 or 8 speed chains have an inner plate width of 2.35-2.45mm. So, you shouldn't have any problems swapping to a 8 speed chainring.

It is when you get to 9 or 10 speed chains where incompatabilites with older drive trains start as 9 & 10 speed chains have inner plate widths between 2.15-2.28mm
silversmith
09-13-06, 11:31 PM
I run a 10-speed Veloce 53-39 crankset on my 82 Letour.

I also swap between 8-speed cassette and 6-speed freewheel wheelsets on the old bike. No problems.


It is when you get to 9 or 10 speed chains where incompatabilites with older drive trains start as 9 & 10 speed chains have inner plate widths between 2.15-2.28mm

I do try to keep cross-chaining to a minimum, as there is so little clearance between the rings. I haven't seen any sign that the chain actually touches the adjacent ring, though.