Front derailleur maximum chainring question
02-02-21, 04:09 PM
#1
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Front derailleur maximum chainring question
Shimano front derailleur specs list the maximum changing size, i.e., teeth. I'm waiting on a FC-T4060 crankset (44/32/22) that I'd like to use with a M4000 Altus front derailleur. But specs for the derailleur say max chainring size 40t.
Can I cheat it or would that be asking for trouble?
Can I cheat it or would that be asking for trouble?
02-02-21, 04:12 PM
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If it is a standard clamp on, don't sweat it. It will be fine.
02-05-21, 06:23 PM
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Apparently Campag brought out Euclid in late '88 to go on '89 model year mountain bikes. They appear to have offered a 24 chainring;
MOMBAT: Campagnolo mountain bike component History
MOMBAT: Campagnolo mountain bike component History
02-05-21, 07:06 PM
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Shimano front derailleur specs list the maximum changing size, i.e., teeth. I'm waiting on a FC-T4060 crankset (44/32/22) that I'd like to use with a M4000 Altus front derailleur. But specs for the derailleur say max chainring size 40t.
Can I cheat it or would that be asking for trouble?
Can I cheat it or would that be asking for trouble?
I have found when going to a smaller than recommended outer chainring, that setting it with a larger chainring/cage gap helps the upshift from middle (triple) chainring. I haven’t had an issue downshifting with the larger gap. But you do need to experiment to find the best setup.
John
02-06-21, 09:11 AM
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Depends on what crank. Record and Super Record 144mm BCD road doubles minimum tooth count was 41. Record triple was 36, although 3rd parties made compatible rings down to 30T. Triomphe and Victory 116mm BCD was 35T.
02-07-21, 10:15 AM
#8
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The curve of the derailleur won't exactly match the circumference of the chainring, but it'll be close enough to work. I've learned that you can mis-match them by quite a lot. The biggest concern is that you'll go past the total teeth difference that the derailleur can handle. For a triple, that's usually 22-24 teeth. I'm currently running a 58T ring on my trike, with a derailleur that's designed for 53T.
