Thread started by eddieboyinla at 05.26.08 - 5:46 pm

ANYBODY?

reply

I MEAN AND NEED A DERAILER FOR AN 8 GEAR DERAILER



eddieboyinla
05.26.08 - 5:47 pm

reply

FOR AN 8 GEAR CASSETE, I NEED A DERAILER



eddieboyinla
05.26.08 - 5:48 pm

reply

do you need a derailer for an 8 gear?



barleye
05.26.08 - 5:54 pm

reply

YES




eddieboyinla
05.26.08 - 5:55 pm

reply

You should be able to use any derailleur. The only thing that matters is the length of the derailleur cage, and that only affects the amount of chain slack it can take up. If you have a big difference between biggest and smallest cog or biggest and smallest chainring, you need a longer derailleur cage. Otherwise, all indexing happens from the shifter. Chains are also specific to particular drivetrains, though I am pretty sure 8 and 9 speed drivetrains from shimano use the same width chain.

Pretty much any derailleur with a cage length that is the same is your current derailleur will work just fine, the only exception is that some SRAM derailleurs only work with SRAM shifters and some recent high end shimano derailleurs are completely backwards. But in general, the vast majority of derailleurs will work just fine for you.

But why do you need a new derailleur? Is your old one bent? That's about the only thing that can 'break' a derailleur.






ideasculptor
05.26.08 - 8:08 pm

reply

i broke the hangeron the fraome, and now........shit forget it thanks guyz for the help, thanks



eddieboyinla
05.27.08 - 12:04 am

reply

ideasculptor: You're right for the most part, assuming we're talking about a newish Shimano setup.

However, Campy derailleurs meant for indexing do have a different shift ratio, so they are meant only to work with Campy shifters. This is in addition to the spacing differences between cogs. Old Dura Ace 7400-series derailleurs have a different shift ratio than all most Shimano derailleurs. It's all covered very well here:

Awesome CTC article on rear shifting

(AKA the page the bike industry doesn't want you to know about)

Of course this also means that Campy shifters pull more cable. This leads to interesting combos when mated with Shimano derailleurs. Right now I'm running Record 10 Ergopower levers with a Dura Ace 7700 rear derailleur and shifting a SRAM 8-speed cassette perfectly.

Sorry for all the bike dorkery.

(I run this because I like Campy levers better but I like Shimano/SRAM everything else better. SRAM Red is nice but HOW EXPENSIVE?)



cabhauler
05.27.08 - 1:15 am

reply