RISKDR1

on a ride this Sunday strange noises began coming from the drivetrain. Kind of snapping creaking sound. At first I thought it was the bottom bracket but on my bench today I think I have isolated it from the cassette. The bottom bracket is turning smooth with no noise. If I press down on the crank with my rear wheel immobilized I can hear the snap, ping coming from the cassette.
I doubt that it is traveling along the chain and manifesting itself in the cassette or is that possible?. I cannot remove the cassette because I do not have the chain whip tool to keep the cassette from freewheeling so will take it by a shop. Is this a possible broken axle?

Andrew R Stewart 

Just about anything concerning noise is possible. But there's a lot you can test for and/or eliminate easily. First thing I'd do is to ascertain that the cassette cogs are tightly held by the lock ring. trying to wiggle, rotate, pry them WRT each other might show some slop. Removal the rear wheel and it's QR skewer and check the axle's spin and integrity. Measure the chain's pin to pin length over 12" for chain wear. Squeeze pairs of spokes together to see if the spokes have notched each other at their crosses. Check for chain ring bolt looseness. Check for crank arm retention/tightness.

You say that you think the noise is from the cassette? How old is the bike/cassette/chain? How much rain riding has it seen? Is the chain dry of lube? can you duplicate the noise with the wheel removed and by hand trying to emulate chain tug on the cassette?

Do we even know if the cogs set is a cassette? Andy.

RISKDR1

I checked crank bolts for proper torque. OK. I checked BB moveable retaining ring for proper torque. OK. the chain and cassette are about 1000 miles. checked chain ring bolts. OK. I am quite sure it is from the cassette since when it makes the click/ping i can detect a small amount of rotationa movement. I will check spokes and axle for possible involvement.

Thanks for the feedback.

Andrew R Stewart 

The more you write the more I think of freehub/freewheel bearings and or ratchet pawls being raw. Andy

RISKDR1

This is a bike I built for a friend. He tends to be a clean freak and washes his bike down with soap and water followed by a hose just about every time he rides it. You could eat off the rear cogs. I am beginning to think he has washed all of the lube out of the freewheel somehow. I have the same exact hub and cassette on my bike and never wash the cassette. It has many thousands of miles and no noise.