My DRZ 400e (2003) has recently started to make new noises (never a good thing). At first it was just a hollow non descript sound from the engine area but two days ago its started doing something really odd. There is a top end hollow rattle as before, but when I get the engine up to high revs (97kmh to be exact in top 14/47) the whole bike resonates like a tuning fork and rings so clearly that I can hear it loudly above all other bike noises....

My first though was resonant frequency of some random loose bit, but I´ve had the bike stripped down today and can hear the start of the sound when the bike is at tickover stationary. It doesnt change when the clutch is in or out. All ancilliary bits have been tightened properly.

I used the old screwdriver as a stethoscope trick but its hard to figure out exactly where the sound is coming from (/unusual...). I think its top end area though. It also tends to be quiet on startup when cold and get worse as the bike heats up (oil viscosity related...).

I know diagnosing stuff over the internet is prettyy hard but any advice would be gratefully recieved. I am currently in Spain and need the bike in October for a desert trip and so have a little while to sort the issues.

All power is fine, the bike shows few other symptoms. The plug is perfectly healthy and the engione is otherwise behaving itself....

Ideas......Cheers as ever,

Dave