[laackund]

new f. der. help!

im trying to figure out what clamp size i need for a front der. i just got a used nrs frame a while back on ebay. would it be as simple as measuring the circumference of the seat tube where the old clamp marks are and figuring out the diameter in mm?

 

[Zanetti]

Measuring the diameter of the tube is all you have to do. Most mountain frames today use either 1 1/4" (31.8mm) or 1 3/8" (34.9mm) front derailleur clamp.

 

[laackund]

Measuring the diameter of the tube is all you have to do. Most mountain frames today use either 1 1/4" (31.8mm) or 1 3/8" (34.9mm) front derailleur clamp.

does it matter if i run an 8 speed system with a "9" speed derailleur. ive always thought it doesnt matter, but xt discriptions on jenson/pricepoint... say they are designed for 9 spd.

 

[Zanetti]

does it matter if i run an 8 speed system with a "9" speed derailleur. ive always thought it doesnt matter, but xt discriptions on jenson/pricepoint... say they are designed for 9 spd.

The nine speed front derailleur cages are slightly narrower than eight speed. If you're using an indexed front shifter, you could run in to problems, but with a friction type shifter, it should work fine.

 

[laackund]

The nine speed front derailleur cages are slightly narrower than eight speed. If you're using an indexed front shifter, you could run in to problems, but with a friction type shifter, it should work fine.

does that apply to the rear derailleur? or will that work w/ 8spd cassette and xt rapid fire shifter?

 

[Hecubus]

does that apply to the rear derailleur? or will that work w/ 8spd cassette and xt rapid fire shifter?

The rear derrailleur doesn't care how many gears there are in the sprocket. It just needs to be able to reach the smallest to largest cog. The indexing is taken care of by the shifter. So to answer your question, yes you can use the same derailleur for 8 or 9 speed. Even 10 speed derrailleurs work on 9/8.