Help needed - Front mech issues

[mk1fan]

Right, I may well be being stupid here but I just can't get the front mech set-up correctly on my old commuter - a Scott Roadster S2.

It's an 8-spd Sora mech but I've fitted a 9-spd set-up (I had been running it as a s/s).

The set-up is Deore XT 9-spd shifters, 105 9-spd rear mech, Sora 8-spd front mech. The rear is silky smooth but the front will only accept the chain being in the middle of the cassette otherwise it just rubs on the side of the mec.

Do I need to get a 9-spd front mech too?

BTW I've stripped and rebuilt it ready for selling, I'm not keeping it.

[atom111]

The shifter will determine the shifting, can't see why it would make much difference having an 8 front mech other than if the 8 mech is narrower

Does look like you are building the bike in a squat

[atom111]

Also googling around it would appear that a rubbing chain in some combo's is a symptom of what you are trying to do.

Maybe worth finding the cheapest 9 speed front mech you can and fit that at least it will save the inevitable and potential feedback issues

[mk1fan]

Wiggle do the Tiagra 9-spd item for £17.95 so I'll give that a go.

[rhinochopig]

I do nearly all my own maintenance and I have to say that some front mechs can be an absolute st to fettle. I took the front of my whyte 46 for something (can't remember now) and after spending a day at trying to get it to work I had to give up and take it to my LBS. Some FM are a doddle, others are a black art.

[Ren-Raku]

mk1fan said:

Wiggle do the Tiagra 9-spd item for £17.95 so I'll give that a go.

If you're going to be buying off the web, ChainReactionCycles.com seem to do some cheaper ones that should be just as good.

[gorisan26]

Two things to consider, is the front mech designed to run triple (they make two types) and also is it designed for drop bar shifters or normal flat bar shifters, the differance is how far the cable pinch bolt is from the top pivot. Ones for drops have the pinch bolt almost on the top pivot thus needing less cable pull between the gears.

A mech designed for triple cahinset has a longer more curver cage to cope with all three ring shapes!

Have you ever had it working on that bike?

P.s if you let me know what diamater of you're seat tube I can let you know the part number of the mech you need,

Hope this helps

[mk1fan]

The mech is the OEM item that came with the bike - which is a flat bar bike with a triple.

I had it working fine before I went s/s (it was still 8-spd rear).

Diameter of the seat tube is 34.9mm. CRC have a Deore 9-spd item for £14 ( http://www.chainreactioncycles.com/Models.aspx?mod... ) so I'll give that a go.

[gorisan26]

The deore one would be a little tight on a road triple, I'm sure you can get a tiagra flat bar triple that would work better, have a search or a word with a shop.