hi there,

changed chain and sprocket about 4 months ago, lined back up wheels ( if i free wheel with no hands it doesnt pull at all to any side which would indicate wheels aligned) . now i tightened with torque spanner to the 55nm as stated in manual along with thread lock. yday when pushing bike back to turn it heard a crunch. sprocket bolt had come loose and as pushing back pushed out sprocket cover cracking it!!!!!! have one ordered and dont want same to happen again. tightened it again and took for little spin and same shit, sprocket bolt loose again!!!! threads are fine, any suggestions please?

thanks for reading
blackduck

blackduck wrote:hi there,

changed chain and sprocket about 4 months ago, lined back up wheels ( if i free wheel with no hands it doesnt pull at all to any side which would indicate wheels aligned) . now i tightened with torque spanner to the 55nm as stated in manual along with thread lock. yday when pushing bike back to turn it heard a crunch. sprocket bolt had come loose and as pushing back pushed out sprocket cover cracking it!!!!!! have one ordered and dont want same to happen again. tightened it again and took for little spin and same shit, sprocket bolt loose again!!!! threads are fine, any suggestions please?

thanks for reading
blackduck

Sorry BD, but clearly they're not.

If you lather it up with strong threadlock you might be lucky enough that it stays put. I have also seen folk put a blob of weld to set the bolt to the sprocket, that'll do it, but you'll need to be careful with a grinder when it's time to replace the sprocket again.