Clunking sound coming from rear axle

[FrostyCamel]

Hi this is my first post on this forum. I started bicycling about 6 months ago as a way to stay in shape, but seem to have become obsessed! I feel all out of sorts if I can't go on my daily ride.

I have a clunking sound that seems to be coming from the rear axle, but only when I'm pedaling. I have seven speeds on the rear wheel, and hear it the loudest in about 4th. I don't hear it at all in 7th or 1st. I have cleaned and oiled the deraileur wheels and have taken the rear wheel off and examined the axle, but did not take it apart. The bearings seem good and I can't detect any looseness that would explain it. Also, it only happens when I am riding. I have tried to turn the bike upside down and turn the crank, but I can't duplicate the sound. Also, I can feel the sound throughout the whole bike as kind of a thump.

I live in a small, isolated town in the rural south, so there are no local bike shops anywhere around that I have been able to find. I am generally a pretty good DIY'er, but I am baffled at what could be causing this sound. I have been riding anyway, but the sound and the thump keep getting worse. If anyone has any idea what this can be and how to fix it, PLEASE HELP.

 

[oldbobcat]

The problem could be a a worn out chain, worn out freewheel or cassette cogs, a damaged freewheel or cassette body, or damage inside the hub, like a broken axle.

Most likely you're going to have to take things apart and test the components, and to do this you're going to need some troubleshooting experience and a couple of specialized tools. Which ones you'll need you won't know until you know more about what kind of hub you have. Frankly, my best suggestion is to pack the bike into the back of a pickup and drive it to the nearest city and find a bike shop. Whatever is wrong, it's most likely you'll need parts, and you're going to need a shop's help finding the right ones.