Setting up a front mech properly and chain rubbing
Setting up a front mech properly and chain rubbing
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Clio200pat

Original Poster:

157 posts

217 months

Thursday 16th February 2012
quotequote all
Afternoon,

I used to mountain bike when I was younger. Over the last couple of years I've started commuting to work on a road bike. I've always wanted to get into mountain biking again and over Xmas purchased a frame and all the bits and built one up. It's now all finished but I have a problem - for the life of me I can't set the front mech up properly!

Is it usual for the chain to rub on the higher or lower extremes of the rear block when in any of the three chain rings up front?

I know you shouldn't ever use top - top or little - little, but from memory on previous mountain bikes I've always been able to get all the gears on the back especially on the middle ring. I'm pretty sure it is setup correctly too.

Setup is 9 speed front mech, rear mech, shifters, cassette and chain. One thing that I thought was that it could be the spacing on the chainset which is RaceFace Evolve XC, so it might be 10 speed. Not sure if this make s a difference?

Any advice gratefully received.

Gooby

9,269 posts

263 months

itsnotarace

4,685 posts

238 months

Thursday 16th February 2012
quotequote all
Use the barrel adjuster to change cable tension until it stops making noise, cable is probably a bit lose is all. Make small 1/4 turns until it stops. You may need to adjust the (+/-) limit screws slightly as well. Again small adjustments at a time

deadtom

2,769 posts

194 months

Thursday 16th February 2012
quotequote all
ooh boy front mechs can be an absolute arse to set up

have you checked the height, angle, high/low limit and cable tension?
is it shifting correctly?
does it rub at both extremes of the cassette in all 3 front chainrings?

not sure if the RF evolve chainset is intended for 10 speed or not, but i dont think it would make a difference to the rubbing if it was, though shifting might suffer for using 10speed chainrings with 9 speed everything else.

shalmaneser

6,426 posts

224 months

Thursday 16th February 2012
quotequote all
the single most important thing with front mechs is getting the height right. Once you've done that then make sure the cage is completely parallel to the chainrings and the rest is a piece of cake.

Clio200pat

Original Poster:

157 posts

217 months

Thursday 16th February 2012
quotequote all
Thanks for the replies!

I am pretty sure I have got the height correct and it is sitting parallel to the chain rings. I'll have a look tomorrow and report back.

Cheers Patrick