A few days ago I had a knocking noise from the bike. Initially I thought it was the seat post worn, so I changed it for a spare I had kicking around. It seemed to stop for a few rides, but after I got back from my break in Scotland, and went out, it was back.
So i pulled out the seat post, re greased it and checked the torque on the saddle rails, checked the pedals and oiled the contact points. Next ride, nope knocking galore, especially on the hills.
OK, now its time to get serious. Loaded the bike up into the work stand and stripped the whole drive train down. I even removed and cleaned the chain rings. I removed the rear dérailleur and saw a movement in the hangar. It was loose. The two little screws that hold it onto the dropout had loosened, and given it a slight movement. This movement would cause it to knock on the frame when torque was applied. Could this of been the source? While this is obviously an issue, the rear wheel QR should of held this tight. But, of course it’s possible this was at fault.
However, the knocking and scraping resumed on the next ride. So, I thought back to changes I’d made. One of those changes was the seatpost. I’d installed a carbon seatpost, and out of pure laziness I’d greased it, rather than using gripper paste.
Removing the post, the grease had a “pooled” appearance. Cleaned the grease off, and cleaned the seat tube well. A good smearing of carbon paste, and refitted.
The next ride was better, but I did hear a couple of knocks/scraping but no where near as bad. It kind of sounded like chain sticking to the chain rings, and during the course of the ride, which was wet, it seemed to get better. Could of been the chain being sticky? Quite possibly as I may of over applied the squirt lube, and the rain cleared it off.
So a really good deep clean and a different lube applied. Let’s see what happens.