I am building up my first bike and need help diagnosing a noise I discovered tonight.
Tonight I installed the chain and rear derailleur. Functionally it works perfectly; shifts through all the gears without problem. There is, however, an annoying clicking coming from the rear derailleur area. When I spin the cranks at a normal speed, the rear part of the system just sounds noise. But when I turn the cranks really slowly, it seems to make one click each time a link on the chain enters the pulley on the derailleur. And that is where the sound seems to be coming from. But I can’t figure out exactly what is causing it or what I need to do to fix it.
Does anyone have any thoughts on what this might be or how to remedy it? SRAM components if it makes any difference.
Check the chain as it exits the top pulley and engages with the freewheel cogs. If the two are too close this may cause a slight “adjustment” for each link as it is trying to mesh with two different sets of gear teeth. Does the rear mech “jump” with each click, or does it remain still?
If you used a quick disconnecting link like a Connex, that could cause this sound. If you used a pin, then maybe the chain got pinched when you installed the pin. Check to make sure all links flex freely.
I would also check the alignment of the RD to the cogs. even though it’s shifting smooth without a load, if the RD is offset slightly to the larger cog it will cause the chain to catch the larger cog then slip down onto the intended cog…that can cause the exact sound you mention. If it’s coming from the bottom pulley then not too sure…but my guess it’s the alignment of the RD to the cassette or as previous poster mentioned the location of the RD to the cassette…also check chain length…if your chain is too long when it’s taking up the slack in a low gear it can rotate up into the cassette.