Bicycle Mechanics - Front Derailleur Marked 42T

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View Full Version : Front Derailleur Marked 42T


tommyd49
05-08-08, 10:59 AM
I have a bike with a 42 tooth crankset which I want to change to a 48. I already have the right size BB and chain, but on the bike atm the derailleur is marked 42t. Will I need to use a different one or should this be ok?


DMF
05-08-08, 12:52 PM
The curvature of the FD will be more severe than an FD for a larger ring. (I'm assuming that you're talking about the largest ring?) And you'll have to move it up to clear.

The matching FD would shift better, but the current FD might shift quite well enough. I'd try to use it and replace it only if you don't find the shifting acceptable.

Al1943
05-08-08, 08:02 PM
I'm wondering if the 42T is actually the derailleur's total capacity instead of the chainring size.

Al