front mech problems

[phil120867]

help, I've been building up a 2001 Gary Fisher big Sur and I've installed a Deore mega nine front mech, I was out tonight (in the pissing rain) but it would drop onto the granny ring as the pivot hits against the frame. I'm assuming I've bought the wrong part but what retro part do I need. Cheers
Phil

 

[Gerry Attrick]

Do you mean it would not drop onto the granny ring?

If your chainset is square taper, it could be it is going too far onto the bottom bracket, putting the chain line out.

 

[Bigtwin]

Do you mean wouldn't drop?

 

[phil120867]

yep i do I've still got mud in my eyes

 

[phil120867]

and its a new hollow tech 2 deore chainset

 

[Gerry Attrick]

You did buy the correct size bottom bracket for the shell?

If you did, what diameter is the seat tube where the mech clamps on? If is oversized, it could bring the mech too close to the chainset.

 

[Bigtwin]

Got the cage at the right angle?

 

[phil120867]

Ahh. I might have a few spacers left over so I might refit the BB and see it that works, you may have just saved me a few £. The cage is fairly spot on I've built up lots of bikes before but this is a new problem to me, I think it might be the BB size. Its been a pain in the arse to try to fit new kit on a 01 frame, i didn't think parts had changed that much!

 

[phil120867]

I just thought I'd let you know that I have just resolved the issue by fitting 2 spacers. Lifting the crank set a few mms further away from the frame seems to have done the trick. thanks for saving me a few quid!

 

[Gerry Attrick]

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