[panhndl]

My drivetrain recently developed an odd clicking sound not unlike the free hub. This clicking sound sort of sounds like it is coming from the spokes, but only occurs on two of the gears on the cassette, no matter which chainring I am in. On one of the gears, the clicking sound occurs the entire revolution and on the other gear it only occurs half a revolution, when I'm mashing on my right leg.

I recently was fitted to my bike, and now hear the sound. I can't figure it out and my riding partner hasn't been able to either.

Any ideas? Oh...at the fit, we didn't use the rear wheel and didn't mess with the drivetrain at all.

 

[FBinNY]

It could be as simple as the sound of the chain passing a shifting gate on chainrings, and dependent on the feeding angle, which is why you only hear it in certain gears. Things like the condition of the chain, and the chain lube can affect this.

OTOH, it could be from cleats, pedals, cranks, BB, chain, chainrings, cassette, rear hub, saddle, stem/fork, or anything else. Try to use the timing to get a clue, ie. exactly where in the pedal rotation it occurs, then look at where the chain is engaging or dis-engaging at that time.

If that doesn't help, you need to start eliminating things one at a time, and i suggest you start at the simplest, like swapping pedals, or other easy component switches, before you getting into more complicated work like checking the bottom bracket.

You should also scroll through some of the "odd click" threads here for some insights to how frustrating this chase can be, and for some more places to look.