Motorcycle Repair: engine noise, kawasaki ninja, leak down test

Question
hello mark i have a 1992 kawasaki ninja zx1100 it started to make a noise like it had a knock in the motor but it does it sometimes and sometimes it doesn't i checked the valves and they are fine could something came loose somewhere else. buck500@hotmail.com     thank you   buck

Answer
Hi Buck,

I suspect the knock may be caused by the combustion process. Especially if the engine runs quietly during other times.

Pre-ignition detonation may cause such noises and make you think the connecting rods are coming apart.

Try another fuel, clean or replace the spark plugs, and montior the problem.

Listen to the engine with a mechanics stethoscope. Check cylinder compression. Follow with a leak-down test if compression readings are not within service limits.

If the problem persists, have a lcoal tech inspect it for you.

Respectfully,
Mark Shively