Knocking while pedaling

[doctorold]

I have a problem of a knocking while I'm pedaling. Pedal or crank arm is not hitting frame. Pedal is tight. Crank arm is tight. It does knock at the same point of pedal stroke (left pedal straight up). I can actually sort of feel it in the bottom of my shoe when pedaling. It sounds like when I was a kid and the pedal hit the kickstand that was not put up all the way. Difference being it does not make the knocking sound on every stroke. Just most. Thoughts, suggestions, ideas on what this could be would be much appreciated.

 

[alfeng]

FWIW. If the sound isn't present when the bike is in a workstand ([COLOR= #808080]or, when someone is holding the rear wheel off the ground & you are turning the crank[/COLOR]) then [COLOR= #ff0000]check your cleats[/COLOR] ...

 

[davereo]

Originally Posted by alfeng .

FWIW. If the sound isn't present when the bike is in a workstand ([COLOR= #808080]or, when someone is holding the rear wheel off the ground & you are turning the crank[/COLOR]) then [COLOR= #ff0000]check your cleats[/COLOR] ...

Check your cleats as stated. I had a screw that held the gripper on a cleat back out just enough that it was getting caught on the spring retainer plate of my pedal making a noise like you are describing.

 

[oldbobcat]

Crank arm hitting the front derailleur cage? Just checking.

 

[swampy1970]

Possibly dead bearings in the bottom bracket

 

[doctorold]

I gave up trying to figure it out and dropped it off at my LBS. The guy there agrees that it's probably the bearings in the bottom bracket. I'll find out later after he gets into it. Thanks for the responses everyone.

 

[74extiger]

I had knocking from my crankset. Same symptoms and conditions you describe. It turned out that the bottom bracket was a little too short for the frame, so the inner chain wheel was rubbing the rear stays. The bike was custom built with Campy Ergo.

Who wudda thunk it?

Gary Curtis

 

[doctorold]

This is good....I get my bike back and tech tells me he took it apart, inspected all, bottom bracket is fine. Greased and put it all back together and it's fine (or seems to be). Took a few pedal strokes and no sound. I'll tell you after a few miles how it's going. But I loved what he said: "frankly, I have no idea what the probably was".

UPDATE: Rode 24 miles today without a peep. Running as smooth and quiet as ever. Great day to be out. 55 and sunny. Didn't miss the cycle trainer at all!