I rolled 1000 miles since getting my old Paso back on the road and after the last ride this past Sunday, the bike has a strange squeak to it. It is really, REALLY loud and I can hear it over the engine. Last night I pulled the bodywork off the bike and removed the timing belt covers. The belt tension is fine and all the bearings for the tensioners appear to be ok, also.

The squeak doesn't sound like a bearing and with how loud it is, it doesn't really sound like it is coming from inside of the engine. It sounds like two peicing of metal rubbing on each other at the same harmonic frequency as the idling rpm. It sounds like it is coming from everywhere on the bike, though. I'm thinking about dropping the oil and filtering it to see if there is any metal or other parts that should not be in it. I'm also thinking about going throughout the whole bike and check the torque of all the bolts. Other than this, I have no idea.

Here is a .MOV movie file of the engine running, so you can hear the engine yourself. Any ideas?

http://www.desmodemon.com/misc_pix/paso_squeak.mov

Clutch bearing??

Alternator cover bearing makes an awful, loud noise when it goes bad.

its really easy to pull the clutch cover to check that stuff out, since its a dry clutch theres no mess either. John

thinking of it and what John said, remove the clutch cover and start the engine, then you`ll know instantly if it`s that bearing or not.

the clutch bearing worn generates a vibration on the handle lever when you pull it lightly and stops when you pull it strongly.
The alternator bearing is easy to inspect and you might find it worn and rosty!
If you need some tip for the clutch bearing, I'll give you

Sounds like alternator to me too.
Good luck.

A screwdriver handle held to the ear and the tip placed around the engine (alt cover vs clutch), should help trace the souce. Use it like a stethoscope.

If you remove the sparkplugs and turn the engine over by engaging a gear and turning the rear wheel you will hear this noise all the easier and hopefully where it is from.

I've done a few checks and have listened to several points on the engine with a screwdrive-to-the-ear method and cannot pinpoint anything obvious. I'm probably going to borrow a mechanic's stethoscope from a buddy of mine and if that doesn't help me pinpoint it, I'll probably take the Paso back off the road until I can figure out what is wrong. I don't see a point in paying for insurance if it is going to sit, and I have to do a timing belt change and valve adjustment on the Monster, ST2, and 748 in the next few months. If I had the extra money to burn, I'd take the bike to someone else to fix for me, but I don't have the extra money to spend.

With the bike sitting for at least six years, I was expecting it to give me troubles once I got it back on the road, but for some reason, this has drained away the last of my motivation when it comes to motorcycles. I haven't touched a bike in over a week (other than starting up the Paso and trying to determine what is wrong with it). I'm hoping to kick myself in the butt and start commuting tomorrow.....and I've got the Ducks Fly South rally sponsored by US Desmo in two weeks, so I'm hoping that motivates me, again.

I am wondering if this squeak can be caused by the starter sprag - if that might be another possible source. Early on my bike developed some chirping, but it was the throw out bearing.