QuestionHi, I recently bought a Kawasaki GPZ500. It's a 1997 model, but in good condition and has only covered 8000 miles.
I've noticed a strange knocking from the engine compartment on long runs - you can notice it especially when you drop the revs, (the knocking sounds as if you have the bike in the wrong gear and is about to stall) - when you put the bike in neutral,you can hear a strange rattling noise, but this soon disappears.
The bike runs ok though and there is no problem when running the bike at fast or low speed.
The knocking is annoying though and is accompanyed by a sound rather like the chain scraping against the frame.
Any clues ?
AnswerHi Kashif,
You provided good descriptions, but I would need to hear the sounds to accurately diagnose the source of the sounds.
The following parts may make noise as described: camshaft timing chain and tensioners, transmission gears, clutch, excessive valve clearances, oil pump, alternator, and final drive chains.
Connecting rods, valves, and pistons make noise, too when failing or defective.
I recommend having a local tech give a listen.
Try a mechanics stethoscope or long screwdriver with the tip against suspected engine parts and the handle end to your ear. Listen for the source of the sounds.
Respectfully,
Mark Shively
