9 speed chainrings

Steve · Post by **Steve** » 23 Jul 2007, 3:59pm

Can I use an 8 speed chain on a chainset designed for 9/10 speed (eg FSA CFJ compact)?

reohn2 · Post by **reohn2** » 23 Jul 2007, 5:33pm

I've been using 8sp chains on 9sp chainrings for about five years so I'd say yes,though mine are TA rings.

Post by Si » 23 Jul 2007, 6:06pm

I have too - mine are ultegra rings with a sram 8spd chain.

CJ · Post by CJ » 24 Jul 2007, 3:47pm

Centre-to-centre distance is the same, only the teeth are fractionally thinner and the rings below the teeth a bit thicker, so the narrower 9 or 10-speed chain can't jam in the gap between them.

Hence the only likely problem is the wider 8-speed chain rattling against the side of the next bigger ring when the inner ring is engaged with the small end of the cassette. But these will be duplicated "cross chain" gears, that are less efficient and wear out the chain faster than similar gears provided by the other chainring(s).

So no problem: any nasty noises will only help remind you to shift out of gears you shouldn't be using anyway!