Front derailleur spec question
07-03-08, 10:33 PM
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Front derailleur spec question
I picked up a Shimano FD-M751 for $10, thinking to replace the el cheapo FD on my mtn bike. The bike has a 42/32/22 crankset, and a 7-speed cassette in the back. Now, according to Shimano (https://techdocs.shimano.com/media/te...9830611894.pdf), the FD has a 22T capacity, so my 20T capacity crankset should be fine, right? The doc also says the large/intermediate chainwheel *minimum* capacity is 12T; my bike has a 10T difference. Will this cause a problem? If so, a description or link to details would be very much appreciated.
07-04-08, 05:19 AM
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I'm thinking that you'll be OK. You might have to install the derailleur 1mm or so higher on the seat tube to keep the cage from hitting on the middle ring.
More important are what kind of shifters you are using and all of the mounting issues: top pull vs. bottom pull, top swing vs. bottom swing, and clamp diameter.
More important are what kind of shifters you are using and all of the mounting issues: top pull vs. bottom pull, top swing vs. bottom swing, and clamp diameter.
07-04-08, 11:28 AM
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Thanks, RG! Both old and new are top pull and bottom swing, and the new clamp fits the tube, so it looks like I'm off to installation and learning how to adjust front derailleurs (I've got two books plus websites for info on that at least). Happy 4th!
