[lml1x]

I'm cobbling a second bike together and here's what I have to work with. A set of 9 speed ultegra shifters, an 8 spd XT cassette and an old Suntour XC Pro rear derailleur. Will this work?

 

[Squidward]

Yes...

 

[Al1943]

The derailleurs will work but you need a 9-speed cassette to go with the 9-speed shifters. It will fit the hub.

Al

 

[Spoke Wrench]

I'm cobbling a second bike together and here's what I have to work with. A set of 9 speed ultegra shifters, an 8 spd XT cassette and an old Suntour XC Pro rear derailleur. Will this work?

I wouldn't bet on it. 9-speed shifters and an 8-speed cassette aren't going to work together very well. Shimano shifters and a Suntour derailleur isn't a match made in heaven either.

 

[Squidward]

The derailleurs will work but you need a 9-speed cassette to go with the 9-speed shifters. It will fit the hub.

Al

I guess I should explain my answer above. I completely forgot that there are two different series of Suntour derailleurs: pre-95 and post. Pre-95 derailleurs move more per cable pull than Shimano derailleurs. As it turns out, a Shimano 9-speed shifter moves enough cable to shift a rear Suntour derailleur across 7 and 8-speed spacing as long as you use a Shimano cassette. Shimano cassettes have equal spacing across the entire cassette and they change the amount of cable pulled between the two highest gears and the rest of the cluster. Suntour did the opposite: they widened the cluster at the two highest gears and kept the spacing of the shifters the same. Post-95 they copied Shimano.

My Bridgestone is running Shimano 105 9-speed brifters with a Suntour GPX rear derailleur (originally 7-speed - from '89) and Shimano 8-speed rear cassette/hub combo. Works like a charm.

 

[lavamantis]

Wtf?

I'm cobbling a second bike together and here's what I have to work with. A set of 9 speed ultegra shifters, an 8 spd XT cassette and an old Suntour XC Pro rear derailleur.

Dude, is this a high-school project?

One word: eBay