Crank spin question
07-19-11 | 10:07 PM
#1
Thread Starter
Senior Member
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From: Gulf Breeze, FL
Bikes: Rossetti Vertigo
Crank spin question
Last night I was doing some bike maintenance on my daughter's BMX bike and my Giant. With the chain on I noticed that the crank on the bmx would spin around several times with just one big backwards throw, while the crank on my bike would only spin about 1 1/2 times around. Is this normal?
Last edited by pgjackson; 07-19-11 at 10:26 PM.
07-20-11 | 09:35 AM
#5
Sua Ku
Joined: Aug 2006
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From: Hot as hell, Singapore
Bikes: Trek 5200, BMC SLC01, BMC SSX, Specialized FSR, Holdsworth Criterium
07-20-11 | 09:36 AM
#6
Sua Ku
Joined: Aug 2006
Posts: 5,705
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From: Hot as hell, Singapore
Bikes: Trek 5200, BMC SLC01, BMC SSX, Specialized FSR, Holdsworth Criterium
07-20-11 | 10:30 AM
#8
The Recycled Cycler
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Bikes: Real Steel. Really. Ti is cool, too !
On my roadbike with Campy group I can give cranks a light spin and they'll spin several times - the bb feels like it has no friction at all. I think it should spin more freely than what you described.
07-20-11 | 10:35 AM
#9
Thread Starter
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From: Gulf Breeze, FL
Bikes: Rossetti Vertigo
07-20-11 | 11:11 AM
#11
Throw the stick!!!!
Joined: Apr 2003
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From: Charleston, WV
Bikes: GMC Denali
I have found that the freewheel can have a huge effect on how the crankset spins. With one wheel mine only spins once or twice, with a different wheel it will spin several times. Pretty simple to decide if it is the freewheel limiting the spin or the bb. Just take the chain off. 
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07-20-11 | 11:58 AM
#12
I got 99 problems....
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From: Does anyone know where the love of God goes, when the waves turn the minutes to hours?
