vibration on an 89

[turbocamino]

  I have developed an annoying vibration at 3500RPM... it's not there at 3k..and gone by 4k.  I see that the engine mounts aren't serviceable on the 89's?  The carbs have been synched twice as i have seen this suggested,with no effect. I have checked any and all mounts to be sure they are tight.  The bike runs perfect otherwise. Its a vibration i can feel all thru the bike, saddle,pegs,bars.(i have the vibranators bar ends) Maybe there is something that can be done with the (front) engine mount i am unaware of?  The only other thing i can think of  is that i have installed a 1250 piston kit and had to do some minor clearancing to the bottom of the pistons where the small end of the rod is closest to the piston ...thinking about a possible balance problem? i wish i could recall if it had this issue before..but can't remember.  Any suggestions appreciated.

[Pat Conlon]

1) Does it vibrate in neutral while up on the center stand?
If yes, disregard below....(vibes are engine related)

2) Does it vibrate in gear while up on the center stand? If yes, look for a unbalanced back tire.

3) Does it vibrate only while being ridden? If yes...
How's your front tire? Is it cupped? All your wheel weights on?

When FJ's vibrate like you described, the first thing I look at are the tires.

[red]

Turbocamino,

Put a wrench on all the clamps, nuts and bolts that secure the exhaust system.  Do not over-torque anything, just be sure that nothing has become loose.  
If any one exhaust fastener is loose, it can set up a resonance all throughout the bike that can not be located in traditional ways.
Hold a lit cigarette or incense stick all around the header pipes/cylinder head junctions, to see if the exhaust gaskets there are good.  
When those pipe gaskets get old, they crumble into dust, and can leak even when the exhaust studs/nuts seem to be secure.

[ryanschoebel]

Turbocamino,

Put a wrench on all the clamps, nuts and bolts that secure the exhaust system.  Do not over-torque anything, just be sure that nothing has become loose.  
If any one exhaust fastener is loose, it can set up a resonance all throughout the bike that can not be located in traditional ways.
Hold a lit cigarette or incense stick all around the header pipes/cylinder head junctions, to see if the exhaust gaskets there are good.  
When those pipe gaskets get old, they crumble into dust, and can leak even when the exhaust studs/nuts seem to be secure.

Is that what part number 20 is in this fiche? I don't think i have that,or number 8 either, and I have had an annoying rattle coming from the exhaust at that same RPM through my owning of the bike. I thought that it just was that way. I didn't realize there were any dampening gaskets or anything.

[red]

Turbocamino,
Put a wrench on all the clamps, nuts and bolts that secure the exhaust system.  Do not over-torque anything, just be sure that nothing has become loose.  
If any one exhaust fastener is loose, it can set up a resonance all throughout the bike that can not be located in traditional ways.
Hold a lit cigarette or incense stick all around the header pipes/cylinder head junctions, to see if the exhaust gaskets there are good.  
When those pipe gaskets get old, they crumble into dust, and can leak even when the exhaust studs/nuts seem to be secure.

Is that what part number 20 is in this fiche? I don't think i have that,or number 8 either, and I have had an annoying rattle coming from the exhaust at that same RPM through my owning of the bike. I thought that it just was that way. I didn't realize there were any dampening gaskets or anything.

Ryan,

For this fiche, Index 20,
https://www.ronayers.com/oemparts/a/yam/5004259ef8700209bc788296/exhaust
Yep, that is what I was talking about.  They are kinda like ceramic, so handle with care.  
Note which way the old ones have been installed in the head, so you can install the new ones correctly.

I never saw the Index 8 gaskets missing on a bike; not sure that would even be possible.  If you have double-walled header pipes, and they are rusted out, then you have a permanent rattle with no factory fix; Yamaha does not sell the header pipes now (no prices on the fiche).  I have the aftermarket Vance & Hines headers/glasspack, which may still be available, but maybe only by special order.  Good luck with the hunt, if so.

[Pat Conlon]

The pipe bushings #8 and #12 are also important

[racerrad8]

Here is 20) http://rpmracingca.com/proddetail.asp?prod=4BE-14613-00

They are the same on each side and will go in either way.

Here is 12/17) http://rpmracingca.com/proddetail.asp?prod=Exhaust%3A3XW-14714-00-00

I think I stock 8 as well but I can't find them right now. I'll have Robert check tomorrow.

Randy - RPM

[ryanschoebel]

I think I stock 8 as well but I can't find them right now. I'll have Robert check tomorrow.

Randy - RPM

Let me know. I'm going to be tearing everything apart in the morning, so you may be getting an order for them soon.

[aviationfred]

I never saw the Index 8 gaskets missing on a bike; not sure that would even be possible. If these gaskets are missing, deteriorated, or worn out, you would have a serious exhaust leak and would be able to hear it.

If you have double-walled header pipes, and they are rusted out, then you have a permanent rattle with no factory fix; You should have no worries here. The 1989 model uses single wall head pipes.

Nobody has mentioned this yet.... When was the last time the valves were adjusted?

I know that when I installed the 1297 big bore kit and new carbs on my 89, the bike was nearly vibration free.


Fred

[wainot-Phil]

  I would also check your Carby  Diaphragm's Rubbers  ,  Take the 4 Diaphragm's  out , hold each one up to a light and see if they have any holes in them,, I once had a bad Vibration in my 90 model between 2000 to 4000 rpm while the Bike was sitting on the center stand ,    It turned out 3 out of the 4 Diaphragm's had small holes in them,,, Once I  repaired the holes ,, about 90% of the Vibration was gone ,,,,JMO

[turbocamino]

   Thanks guys..some great suggestions and gives me some direction.  It is very much like a harmonic type buzz...could be something is loose?  i will do some poking around in this direction first. thanks

[RPM - Robert]

I think I stock 8 as well but I can't find them right now. I'll have Robert check tomorrow.

Randy - RPM

Let me know. I'm going to be tearing everything apart in the morning, so you may be getting an order for them soon.

They are here http://www.rpmracingca.com/proddetail.asp?prod=3XW-14755

[Pat Conlon]

   Thanks guys..some great suggestions and gives me some direction.  It is very much like a harmonic type buzz...could be something is loose?  i will do some poking around in this direction first. thanks

Also, find out if the vibes are rpm related or speed related. Are the vibes at 3500 present in 5 gear the same vibes present at 3500 in 4th or 3rd gear? If the vibes are only present in 5th gear and not in 4th or 3rd, then it's speed related, which means tires or wheels.
We had a forum member who had a Cush drive bearing go bad and he felt the vibes through the entire bike.

[ryanschoebel]

I have had an annoying rattle coming from the exhaust at that same RPM through my owning of the bike. I thought that it just was that way. I didn't realize there were any dampening gaskets or anything.

UPDATE: I bought and installed the #8 gaskets (between header pipes, and collector), and after tightening everything, a few new bolts, and new rubber washer on the main hanging bolt underneath, that rattle is completely gone. No matter how hard or soft I accelerate, in any gear, its totally gone. I am so much happier not having to listen to that!

[Tuned forks]

So it was an exhaust rattle?

Joe