chatter sound

[friesman]

Expert ideas?

Ive got this new sound in the last few days that seems to be coming from low in the bottom left front of the crankcase.

When the engine is idling there is no clatter noise and it only seems to appear when I am under light to medium acceleration (I dont know if it makes it under WOT as the mufflers are making too much noise), as soon as I back off the throttle or pull in the clutch the noise goes away. The noise is not loud in 1st gear and seems to increase in 2nd and 3rd gearand continues in 4th and 5th.

I am afraid it sounds to me like ive got a spun bearing somewhere in the transmission, but I need some experts (........and you guys too:stickpoke:) to weigh in on this and tell me what your thoughts are.

 

Ill enclose i vid that was taken on the weekend an you can hear what I am talking about. it has a bit of an exhaust leak, but I am sure thats not the issue.

 

I have also had the bottom of the collector opened up and the loose pieces taken out so it shouldnt be anything inside the exhaust.

 

 

Thanks in advance for the help everyone!

[dingy]

I know you are saying front of case, but that sort of sounds like a universal joint.

 

Gary

[KIC]

There is also a metal heat shield back there that makes a "chatter sound" on both my bikes since the bolts seem to work through the metal and it just sits there. I am guessing I have to pull the rear and the shock to get to it and to try to remove the bolts to fix. You can reach through the side and try wiggling it to see.

[frankd]

I agree with Gary...sounds like something in the shaft drive.

 

Frank D.

[Yamamike]

Sounds like a ball bearing going south to me.

[paysaw]

Hi Brian

As you know I replaced my middle gear on the 83 I had.It had a very similar sound.Do you have an oil leak at all? If you had an oil leak on that side of the motor under the middle gear that could tell more of a story. Other than that , it could be an internal transmission upset stomach.:confused24:

[GeorgeS]

Be sure to check the front brake calipers, and also front wheel bearings, just to

eliminate them. Don't really think thats the cause, but worth checking.

 

I did have sort of a similiar sound from my Rear Brake caliper, the pads were loose, and applying brake pad " goop " solved the problem.

[friesman]

Hi Brian

As you know I replaced my middle gear on the 83 I had.It had a very similar sound.Do you have an oil leak at all? If you had an oil leak on that side of the motor under the middle gear that could tell more of a story. Other than that , it could be an internal transmission upset stomach.:confused24:

 

 

No oil leaks anywhere. But it does sound suspiciously (but not exactly) like it did just before the middle gear/u joint assy blew out in California in 08. and it disappears when I pull in the clutch or left of the gas, so its not the wheels or brakes as that would be constant. ( I think) .

Did you have good luck with replacing your ujoint assy without taing the engine out?

 

Brian

[ddoggma]

I had a clacking sound, on excel and decell. When I took off my old collector. The bracket on the top was busted in three places. With the new unit on, all those noises are gone. Alot of the stuff I was experiencing was from the collector being shot. Now my baby is a hottie again...lol I'm scraping my toes for the first time in a while:cool10:

[friesman]

A mechanic friend and I had a look at the bike today and it looks like the middle gear assy is gone again This is the 2nd time, I wonder what would cause this to fail, could there be something out of line? I dont baby my 85 but I dont abuse her either and I am just fed up at this point. I really hope I dont have any trans damage this time, but I am just going ot fix it if the bill is going to be resonable and sell it, I just cant seem to depend on this bike.

 

Brian

[paysaw]

Hi Brian. Your mechanic confirmed my suspicion. it is a heck of a job but you dont have to pull the motor out to do it.Thats about the only thing you don't have to do, But honestly all you need is time.

You will have to take bags, seat rear wheel and brake, drive shaft and drop part of the swing arm. If you can find someone that has done it before with the right tools and few coffees if you really go at it you could get there in 2 hours or so hoping you have nothing rusted.

Now loosen the pinch bolts( I think there is three of them) that hold that part of the motor together at the middle gear I think there is a rubber boot there too that has to be removed first that has a spring connect to it to make a seal at the middle gear.Then take out the bolts that hold in the middle gear to the tranny. Get a screw driver and wedge it in between the middle gear and the engine case.Pry it gently from different parts of the middle gear and it will slowly come out.You wont think so but it will.There will be numbered shims that will fall out when the gear comes out. Pay attention to their placement as the are used to adjust pinion offset.After some cursing you will get it out. Be gentle with it as you do it.Think about your first girlfriend!!! lol