Bicycle Mechanics - 8 who for 9 what?

OK, I hope there is a simple answer for this question.

I still have 8 speed drive train, mostly shimano STX-RC.
In trying to lighten the load Ive bought new cranks and BB, Race Face Prodigy XC, and SRX.
I checked with the LBS when I bought them, and they assure me that there is no problem using 9 speed front chainrings with 8 speed chain / rear cassette.

However, Race Face's website makes some claim of incompatability.

Ok who's blowin smoke up you know where....?

It's CYA. But, if you worry about it use a 9 speed chain.

7, 8, and 9 speed chains are all the same inside width 3/32". The outer width narrows. The suggestion to use a 9sp chain is a good one if you experience any difficulty. Spacing of chainrings is less critical than rear cog spacing. For practical purposes there is little difference between "8-speed compatible" and "9-speed compatible". I am using 9sp STI shifters with older 6 or 7 sp cranks on two of my road bikes..

Contrary to what pokey said.

I'd suggest sticking with an 8 - speed chain.

If you swapped out the cranks (i.e. 3 front chainrings) and kept the 8 speed cassette, you need to stick w/ an 8 speed chain.

The 9 speed chain is thinner and will not work well with an 8 speed cassette.

An 8 speed chain (wider) will work with 9 speed chainrings. But will NOT work with a 9 speed cassette.

I ran Shimano XT 8 speed with Race Face LP Turbine cranks and 9 speed rings w/o a problem.

BTW what is SRX????? I may be completely off base since I don't know what SRX is, so, if I am sorry Pokey!

L8R

As i rethink it, his 8 speed STX deivetrain may be IG, which shimano says requires an 8 speed IG chain which has a width of 7.1mm which is narrower than the HG width of 7.4mm. Sram says their chains work with IG cassettes ,and the 9 sped is 6.9mm vs shimanos 9 speed width of 6.6mm.what's it all mean.I duno.

Sory a2,

SRX is the type of bottom bracket, the new one... just so there is no confusion.
But I am using a SRAM chain, 8 sp, pc 68? damn if I dont forget!!

Thanks, I think that Race face probobly are just covering any angle... It going on tomorrow... :D

Next week, I ride like hell!!

:lol:

Originally posted by Scooby Snax

But I am using a SRAM chain, 8 sp, pc 68? damn if I dont forget!!

Next week, I ride like hell!!

:lol:

I ride like hell every week. But I keep trying to get better. :(

FWIW, I called SRAM to ask about the difference between the different chain models when they came out with the PC-99 "racing" model. I don't race, but if it were functionally better in some way I would have been willing to pay a little extra for it. The SRAM tech said there is no functional difference between the different numbered models, just cosmetic and weight differences.
PC-59 - has alternating black and silver links
PC-69 - all silver
PC-89 - does have heavier plate construction for heavy duty off-road use
PC-99 - has drilled plates for slight weight reduction
But the rolling/moving parts are basically identical.