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[Closed] Help me understand front derailleurs

 Earl
Posts: 1902
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[#6486314]

I need a new fd for my Genesis Mantle. It has a cable the pulls from under the bb. Looking for a Shimano one. Do I just want a what crc describe as 'conventional'? i.e. not e-type, not top swing, not direct mount.


 
Posted : 15/09/2014 10:01 pm
 P20
Posts: 4265
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The pics on the site show a conventional mech where the clamp is above the mech. Top swing is where the clamp is below the mech. Conventional seem to last longer in my experience. Most mechs are dual pull these days, so they will do both top and bottom cable runs


 
Posted : 15/09/2014 10:04 pm
 Earl
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Ok - so as I understand I can go either conventional or top swing.

What is better for rear tyre clearance?


 
Posted : 15/09/2014 10:19 pm
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Get one with a clamp that fits around your bike's seat tube. It sounds obvious and yet...


 
Posted : 15/09/2014 10:19 pm
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It's generally best to replace with the same style mech as worked before. Unless the previous mech was ripped of by it catching on your tyre.


 
Posted : 15/09/2014 10:21 pm
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Conventional (high clamp) type are generally a bit longer lasting as the pivots can be built a bit more robust than the top swing.

Most shimano can do top or bottom pull these days.

I would advise getting what is on your bike already. Sometimes low clamp type cannot work if the seat tube flares or there are pivots and sometimes the high clamp dont work if there are bottle clamp bosses or other features in the way.


 
Posted : 15/09/2014 10:23 pm
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But it must state bottom pull or dual pull........ there may still be some top pull mechs knocking around, and that won't work.


 
Posted : 15/09/2014 10:24 pm
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But it must state bottom pull or dual pull........ there may still be some top pull mechs knocking around, and that won't work.

You can bodge this by running the cable over the top tube and back down to the mech. Best not though, innit.


 
Posted : 15/09/2014 10:27 pm
 Earl
Posts: 1902
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I bought the frame so there was no old mech to copy - that why I'm asking here. Conventional it is.. thanks.


 
Posted : 15/09/2014 10:40 pm