They do a little bit, I think this was brought up before but can't remember where, you can even notice it from a dead stop leave the bike running and pull the clutch in and out in neutral you can hear it, can't be sure what yours is though? My engine that was got for my bike before I bought it was crashed aswel, what you will never know is how long bike was on its side before engine was killed, u just don't know what parts wer starved of oil and for how long,