Shimano Front Derailleur Height?
04-10-20, 10:24 AM
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Shimano Front Derailleur Height?
Hello,
The instructions for 105 and Ultegra front derailleurs state one should position the front derailleur cage 1 to 3mm above the teeth of the large chainring. Is there any advantage or disadvantage for how close the derailleur cage is to the teeth?
Thanks.
The instructions for 105 and Ultegra front derailleurs state one should position the front derailleur cage 1 to 3mm above the teeth of the large chainring. Is there any advantage or disadvantage for how close the derailleur cage is to the teeth?
Thanks.
04-10-20, 11:49 AM
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Too close and it won't clear when shifting. Too far and it may not catch the chain plates when shifting, and also if it does shift it may throw the chain off the chainring.
04-10-20, 09:34 PM
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Since the cage height above the large ring is adjustable it's simple to try different gaps and determine your own preference. Andy
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04-11-20, 01:49 AM
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I think the 1-3mm is intended to set tolerance, but basically as close to 1mm as possible assuming nothing catches usually shifts the best when everything is designed to work together.
04-11-20, 06:50 AM
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Modern cranks typically have shaped teeth and a some are shorter than the others. Be sure you set the gap over one of the full height teeth or they can hit the cage when you turn the crank.
04-11-20, 09:59 AM
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I usually use a dime for a gauge
