Front mech replacement

venster

I'm changing my front mech on my Trek 1200.

I've measured the diameter of the tube and it's 35mm, from what I've seen you can get 34.9mm mechs. And I'm assuming mine is a band-on type because I can take the whole thing off if I wanted to?

Does it matter if I get 9 spd or 10 because there seems to be very limited 9spd ones out there.......

( It's a compact chainset so a double is required )


Also, could I continue to use the band I have and buy a new mech and just swap it over ? Are the screw holes in the same place ?

geoff_ss

I don't really know but common sense tells me that the chain set can't 'know' how many sprockets there are on the cassette. So a front derailleur can be either 9 or 10 speed to choice.

Geoff

redddraggon

Geoff_SS wrote:

I don't really know but common sense tells me that the chain set can't 'know' how many sprockets there are on the cassette. So a front derailleur can be either 9 or 10 speed to choice.

Geoff

It's more to do with the chain width Geoff. A 10 speed derailler cage with be slightly narrower, meaning you're more likely to get chain rub when using a 9 speed chain on certain sprockets.

on the road

It might matter if you're changing up from a 9 speed.

venster

I'm having real trouble finding a 34.9mm band on double front mech, other than the expensive DA. All the cheaper ones are for triples.........

Does anyone know where I could get one ?

I've tried all the ' usual online places '.....

redddraggon

Just get a braze on mech and 34.9mm adapter - that's what I use on my carbon bike.

venster

Ahhh, i thought the adaptors were for the other way around :?

Thanks anyway, I can see light at the end of the tunnel now.

Pity really: I was getting the wife geared up towards the need for new bike !!!