Crankset question
10-07-19, 11:27 AM
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Crankset question
Sorry for the rookie question in advance.
Why does a replacement crank set need to be matched to a certain gear cassette? I have a 3 ring crank how would a crank for a 7 speed differ from one for a 8 or 9 speed? Not alot of upgrade to match a 7speed cassette.
I have a 2017 Trek Verve 1, I'm looking to upgrade some of the components.
Also, with a hybrid, should I use mountain or road bike components. It is just a around town bike.
Why does a replacement crank set need to be matched to a certain gear cassette? I have a 3 ring crank how would a crank for a 7 speed differ from one for a 8 or 9 speed? Not alot of upgrade to match a 7speed cassette.
I have a 2017 Trek Verve 1, I'm looking to upgrade some of the components.
Also, with a hybrid, should I use mountain or road bike components. It is just a around town bike.
10-07-19, 11:35 AM
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The ring thickness and spacing is a "bit" different.
A 9 speed ring should be OK on 7 speed.
A 9 speed ring should be OK on 7 speed.
10-07-19, 12:43 PM
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I run 9-speed cranksets on all 3 of my 7-speed bikes with no issue.
10-09-19, 09:21 AM
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Yes, the ring to ring spacing and the ring thickness can be different. If the ft der is friction controlled then some of these differences are not in play, one just trims the ft cage (via the lever) to eliminate rub. But if your ft shifting is indexed then steps of ft cage movement might not agree with the rings' locations, and chain rub can be more likely. Andy
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AndrewRStewart
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10-09-19, 09:27 AM
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What no one mentioned are the consequences of not being close enough.
Bicycle chains come in different widths. Drivetrain components are spaced so the desired number of gears ends up on the cassette/ freewheel. The chain is matched to that. Having wider or narrower spacing on your chainrings could cause the chain to shift poorly, or even get stuck between rings. The good news is that 5-8 speeds are generally the same spacing, with 9 being close, beyond that, problems with mismatch, especially with indexed fronts.
Bicycle chains come in different widths. Drivetrain components are spaced so the desired number of gears ends up on the cassette/ freewheel. The chain is matched to that. Having wider or narrower spacing on your chainrings could cause the chain to shift poorly, or even get stuck between rings. The good news is that 5-8 speeds are generally the same spacing, with 9 being close, beyond that, problems with mismatch, especially with indexed fronts.
