chain skipping

[Moodyman]

Hello,

I've had a skipping chain for about three weeks and I'm now at my wits end. It was happening when laying down the power - i.e. from the lights but now happens anywhere.

I've gone through various possible cures - replacing the chain, cassette and chainring. Also took the rear hub apart, cleaned, greased and re-installed. The freehub is smooth.The bearings have been changed.

The rear derailleur is perfectly indexed and there are no stiff links.

Around the same time, I noticed a broken spoke (at the J bend) and bent QR skewer near the threads. I can only assume that I must have hit a big pothole and both of these occured together as neither was there during the previous week's maintenance. Spoke been replaced.

The cassette wobbles up and down slightly when bike is in the stand and the wheel is turning. This does not affect the gear change in the stand or on the road. Gear changes are slick and wheel runs true.

Before I order a new QR skewer, could this be the cause of the skipping chain and grinding sound coming from the hub?

The hub axle is straight.

 

[boydj]

If the QR was bent , the axle could be cracked - so it looks straight when not under load, but moving around when you are on the bike.

 

[MrJamie]

Have you checked the gear cable? I think even if it's indexed fine if the run of the cable isnt perfect or outers are gunky it can intermittently not release the cable fully on a shift to smaller sprocket. Also if it runs under the bottom bracket and isnt running perfectly through the guide then frame flex when youre pulling away hard can add tension to the cable moving the mech slightly making it possible to slip. Probably not the cause, but something to check?

 

[musa]

The barrel adjuster may need a tweak