I have 40000 miles on my 96 f3, i bought it with 25k and since i purchased it it has always made a buzzing sound, sounds like bb's rolling around in a tin can, it gets louder under load and is gone when you toll off the throttle, the noise is linked to engine speed not wheel speed, i only recently started trying to track it down and cant figure it out and am hoping for some help, first the things ive tried.
I replaced the exhaust gaskets hoping it was a leak, did nothing, I thought maybe it was the cct so i replaced it with an ape, tried it both loose and really tight and it makes no difference, then i thought clutch bearing so I replaced the throw out bearing with no change in the noise. I suspected the clutch bearing cause when you pull in the clutch the noise is gone, i think thats just because there is no more load.
Im now thinking maybe the valves? Could be valve train noise but its just strange that it gets louder under load and its gone when you roll off the throttle, maybe if these engines had variable valve timing but the valves shouldnt be changing time right? Anyone experienced anything similar or have any advice?

 

Anyone have any idea on what to start looking at? Would it make sense for the clutch to make a noise that changes under load?

 

The noise and behavior you state strongly points to cam chain rattle. If you've replace CCT with an APE unit, then my guess would be that one of the cam guides is either missing or broken. Take the valve cover off and check the top one. Also remove the side cover and I think you can check the other 2. And also make sure the APE CCT is putting tension on the rear guide properly.

 

I recently had toreplace my stator and while i had the oil out i decided to pull the clutch cover and pull the clutch out looking for the problem and didnt see anything in there but the oil pump chain that could be loose, is it normally loose? Nothing around the chain was scored so it didnt look like it was rubbing on anything, anyway, i tried to get the timing cover off but couldnt get it off, ill try again this weekend as well as pulling the valve cover, anything else i should check in the engine while i have it apart? Doesnt sound like rod knock does it?

 

No, rods tend to knock more when not loaded. You said this got louder under load. To me that sounds like the back side of the cam chain getting slack under load/throttle. It will get tighter when off throttle.

It certainly could be something else. But your description would have me checking the cam chain guides first before anything else. Make sure the rear guide isn't stuck. The CCT pushes on it.

My F2 rattles a bit at idle with the clutch out. When you pull it in, it's goes away. That's somewhat normal for the clutch. It's just the basket and plates rattling. But it shouldn't make any noise on/off throttle. I've got no idea about the oil pump, but I've never heard of a problem with them or the chains before.

 

Ok so i tore into the valve cover today to check the top cam chain guide, looks fine, no real wear anywhere on it, bolted in nice and tight. While i was in there i decided to check the valve clearances, i gave up almost immediately after noticing that i cant fit a .0015in (.05mm) feeler in the intake gaps, i double checked my manual to make sure im doing it right and i am, 4 of the 8 exahust valves were within tolerance but not a single intake valve was able to be measured, im guessing thats not good, would that cause my noise? Lack of power maybe? You will also find an attached pic of the inside of my valve cover, lower side of the picture is the exahust side, notice the two burnt sections on 2 and 3? What would cause that?

 

All cam chain guides are in good working order and the cam chain is tight, no marks to indicate its rubbing anywhere

 

Valves would only make noise if they were on the really loose side. You're sound too tight. It would be a good thing to set the valve clearances if they are off. Too tight can cause you to burn valves/seats. That's a lot harder to fix, than adjusting the valve. Plus it will probably make the bike run smoother and have better power. Depends how far out they are right now. Alot of times you can get the valve close by swapping shims around.

As for the noise, I guess the next thing I'd look at it is maybe the drive chain and sprockets. What kind of shape are they in? Are they aligned correctly? Are they bolted on tight? Are they all the right size? I've seen people mix 520 and 530 before. They might make noise under load and go quiet off throttle. Is it possible something is just loose and rattling due to vibrations?

 

I just replaced the from sprocket a few weeks ago because i highway ride alot and was -1 in the front and wanted stock gearing, the old sprocket was fine though condition wise, rear looks good, no hooking, and the chain is a d.i.d 520vx2 but has been on the bike for at least 15k miles, i did at one point ride the bike without any fairing at all and it still rattled so im thinking mechanical, ill dig into the chain more, anyway to tell if its toast before it breaks?

 

Make sure the 520 sprockets are aligned correctly. Many of them require a space on the front sprocket and sometimes it gets put on the wrong side. At 15k I'm thinking the chain is probably getting toward the end of it's life. You can measure X number of links and figure out the % of stretch and go by what the chain manufacture recommends. There are site that will tell you how to do this better than I can.

I usually can just tell by when the chain starts to get kinks. I can also feel when the chain gets snatchy too. I usually start to watch my chains around 18k or so, but that's with a stock size 530.