Hello,
My mom has a 2003 EX500 with a loud ticking/slapping sound that I cannot figure out. She believes the noise is mostly in the crankcase, but in my opinion it is more near the top of the engine. When I do the 'screwdriver to the ear' test it seems loudest at the exhaust rocker arms, though that is all subjective diagnosis.
Things I have done thus far:
- Adjusted the valve clearances to within spec (0.006" on the intake and 0.008" on the exhaust)
- Replaced intake and exhaust camshafts (the lobes were showing signs of wear)
- Tightened exhaust manifold bolts (did not replace the gasket as of yet, but have thought about it)
- Inspected the CCT (it appears to operate fine, the plunger can fully extend and retain its position)
- Basic maintenance (oil/coolant/etc.) there were no signs of metal filings in the oil
Just had the tires changed on it and the service tech said he did not suggest paying for the rubber swap as he did not feel comfortable starting the bike at all.. maybe he is overreacting but it definitely does not sound good!
This noise persists through the entire RPM range and is present when the engine is both cold and hot. It has made this noise since she bought the bike and has gotten worse over several thousand kilometers.
She is not technically inclined so I figured I would try and fix the problem to reduce chances of her being stranded in the country when her bike inevitably self destructs.
https://www.youtube.com/watch?v=c02QBXI8ML4
Bump.
What you up serious internal engine problems from a noise like that sounds like it's in the valve system to me I would get a borescope and then take the spark plugs out and inspect all the valves turning the engine around seeing if any of clips or chips on them or something
Since this question was first posted I have removed the engine and split the crankcase. The crankshaft balancer bushings (the splash lubricated end) were all scratched up, so I will be replacing those.
On the top end, the exhaust cam bearing caps were damaged as well, so I am going to replace the cylinder head entirely. I suspect the previous owner did not install the caps in the proper order during previous maintenance which led to serious damage.
I clearly changed the camshafts with my eyes closed, or I would have noticed the damaged caps and would have determined the cause of the noise long ago.
Before reassembly I am going to clean each part thoroughly with some degreaser/parts cleaner to 'restore' the engine as best as I can. Heck the engine is torn apart anyways, may as well do everything possible to refresh it. The cylinder head gasket mating surfaces are going to be lapped as well.
Hopefully this is the last of the issues causing a noisy engine.
Thank you for the response! 🙂