XT600E - Funny Engine Noise?
I bought this bike about 8 months ago, it's a 1990 XT600E I bought with 4900 miles (7900 km) on the clock, and for about the past month it has been making an odd metallic squeak/whistle/rattleish noise from the top end area (valves?). It only does it when the engine is warm and at moderate-high RPMs (I have no tachometer). The bike now has 6700 miles (10800 km) if that makes any difference.
It also, on every so often makes a hollow knock when I start it, not every time and it's only on the ignition stroke.
Just some odd noises, any suggestions would be greatly appreciated.