Bicycle Mechanics - Too much crank rotation until rear cog set engages

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jeff williams
02-24-04, 07:41 PM
my rear cog set is turning too much after coasting. almost half a rotation on the lowest gear till it engages- close to correct in highest gear.

I've been playing around with different chain rings- The one I am using now is from a 5 speed and I am running a 7 rear cog set. The teeth on the current ring are in a different position\ if you line up the bolt holes, the hills\valley are in opposition. I don't see this causing this slipping of my rear, but it might play with the chain tension.

Any ideas on the cause? and it's a cassette in shimano deore.
I'll put on different chairings and see if it alters, thanks.j

CRUM
02-25-04, 02:51 AM
Is the rear hub a spin on with a freewheel or a casstte/freehub? Regardless, the first thing I think of is one of the pawls inside the freewheel mechanism is toasted or stuck. This means only one pawl is engaging when you turn the cranks. The higher(smaller gear/rear) would only have to rotate a little to engage the remaining pawl. The lower(Larger gear/rear) would have to rotate a larger circle giving the impression of less engagement. In other words, I think the problem is in the rear, not the front.
madpogue
02-25-04, 04:33 PM
Yup, that sounds exactly like a sticky freewheel/freehub pawl. Very common when it's cold (which, I presume, it is presently in BC). You might be able to shoot some lightweight lube into it without taking it apart. Just make sure it's something that's gonna remain thin and slippery as the temp drops.

gwhunt23
02-25-04, 04:49 PM
Not sure if this will help, but make sure that you take off that little plastic guard that goes inbetween the cassette and spokes. This was causing a similar problem with my bike when I first got it.

Good luck!

-Garrett
jeff williams
02-25-04, 11:10 PM
Temperature 44 °F / 7 °C @ 9PM :D

No plastic chain guard, I'm far stripped for that, not even a bottle cage anymore.
I'm going to try the lube and perhaps a dis-assembly of the unit and have it inspected at the lbs.

Is the lubricant packed in say as lithium grease is? I'm wondering if cleaning of the cog set has quickened the breakdown of the lubricant (old)?