Guys, I have an 06 ZX10.... every once in a while I mistakenly take off from a stop in a higher gear than first. When I do I hear a rapping grinding sound. The bike has always done this and today I decided to ask the experts what the hell they think this could be. The front sprocket is solid with no play. When I first heard this I was thinking cam chain. But really if it was the cam chain I doubt the motor would still be running. Clutch? I just don't have a clue. When it happens it sounds really bad. But then I downshift and its fine. Any ideas where this noise could be coming from? It's been doing this for years. Thanks Mike
Hard to say for sure but my money is on the clutch. Firstly, I would suggest making sure you always start in 1st gear as starting in the higher gears puts extra wear on the clutch plates. Just give a double tap down on shift lever at stop to make sure. The grinding could be a couple things but in my older gixxer I actually had the bolt come loose that holds the shift plate on behind the clutch basket. Once torqued back down the grinding noise was gone and I was back on the road.
The simple fix is just start off in 1st gear! You say no issues when starting off that way so there ya go. However, if you want to dig deeper you should start by pulling clutch and check for anything unusual.
Also, check chain slack. Maybe chain is way too loose as well..
