Front mech woes

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SteviePCommencal
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Front mech woes

Postby SteviePCommencal » Mon Nov 12, 2012 18:54 pm

G'Day!

I am having trouble with my Trek Scratch and the front mech, its the 2010 9spd model and currently has an SLX direct mount currently fitted. I have removed the outer chainring and have fitted a 36 tooth chainring.

My problem is that the front mech sits far too high on the frame, I have lowered it as far as it will go but it still drags when on the granny ring and allows the chain to bounce off when on the middle.

My question is, would it be possible to fit a Sram 2 x 10 front mech?, they seem to have a much longer distance between the mount and the cage so would hopefully fit a lot better, there also seems a lot more adjustment on the mounting point

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The Rookie
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Re: Front mech woes

Postby The Rookie » Mon Nov 12, 2012 18:56 pm

As the current mech should be fine in the Granny (it was sold to work with it) it suggests you've messed something up?

What gears at the rear does it drag in?

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supersonic
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Re: Front mech woes

Postby supersonic » Mon Nov 12, 2012 18:58 pm

What model of SLX is it?

SteviePCommencal
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Re: Front mech woes

Postby SteviePCommencal » Mon Nov 12, 2012 19:03 pm

Right, just had a look for the model number but can't find anything

It's a 2010 high direct mount mech.

See, usually I bugger things up but on this occasion I don't think I have! There is a small amount of vertical movement and the chain is scraping on all but the largest 3 rings on the cassette. It is the standard mech and it is the standard 22 tooth chainring

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supersonic
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Re: Front mech woes

Postby supersonic » Mon Nov 12, 2012 19:07 pm

You have lowered it too much! You need to set it up as if there was a big ring still on there. Assuming it worked ok before?

SteviePCommencal
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Re: Front mech woes

Postby SteviePCommencal » Mon Nov 12, 2012 19:14 pm

Nah, it has been like this since I bought the bike (secondhand about 4 weeks ago)

Definitely doesn't need to be raised! Its almost as if the mounting hole on the frame has been drilled in too high

The reason I was wondering about a Sram mech was because there seems to be a lot more scope for adjustment, but I'm a little worried as they are narrower being 10spd

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cooldad
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Re: Front mech woes

Postby cooldad » Mon Nov 12, 2012 20:27 pm

Stick a pic up.
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SteviePCommencal
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Re: Front mech woes

Postby SteviePCommencal » Mon Nov 12, 2012 21:10 pm

Here you go..

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Image

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YeehaaMcgee
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Re: Front mech woes

Postby YeehaaMcgee » Mon Nov 12, 2012 21:37 pm

that looks WAAAAAAAY too high.

Chunkers1980
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Re: Front mech woes

Postby Chunkers1980 » Mon Nov 12, 2012 21:44 pm

Yeah, but not too sure what can be done about the height.

SteviePCommencal
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Re: Front mech woes

Postby SteviePCommencal » Mon Nov 12, 2012 21:45 pm

Yep!

But it won't go any lower!

New mech time, but what will be better?

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Cat With No Tail
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Re: Front mech woes

Postby Cat With No Tail » Mon Nov 12, 2012 21:51 pm

Edit: Never mind, was talking shoyte.

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The Rookie
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Re: Front mech woes

Postby The Rookie » Mon Nov 12, 2012 22:05 pm

I wonder if it's a trecking mech designed for bigger rings, you need the M number, most likely stamped in the back of the cage.

SteviePCommencal
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Re: Front mech woes

Postby SteviePCommencal » Mon Nov 12, 2012 22:09 pm

Just found it and its m661

I thought this was standard SLX

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The Rookie
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Re: Front mech woes

Postby The Rookie » Tue Nov 13, 2012 06:14 am

M661 is indeed SLX, I know direct mount can be funny, on-one do a guide for the 456's which show what will and win't fit.

Tech docs
http://techdocs.shimano.com/media/techd ... 686238.pdf

craigw99
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Re: Front mech woes

Postby craigw99 » Tue Nov 13, 2012 15:22 pm

did it work before you took the chain ring off?
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