Help please with tuning

What can cause so much vibration? I know the usual loose bolts and such or something broken internal. But I have no loose bolts and don't hear or find anyting internal to be broken. When I had the ignition cover off checking the flywheel I also checked to see if there was any play in the crank bearings, there wasn't. I checked the balance shaft as well, it was nice and tight and moved freely when the engine turns over. No metal shavings were in there, but then again I have a magnetic drain plug that I haven't checked yet.

Check the pilot and main air passages and jets, check that none of the cross holes in the pilot are closed, and that the needle jet hasn't been worn oval shaped.

What can cause so much vibration?
When checking motor mounts, be sure to include the swing arm pivot and head stay, and also check that none of the mounting points at the frame and engine are cracked. Be sure the balancer is timed correctly if it's been apart, and if there's any chance it would have a 2000 model crank in it, check the key on the balancer gear (later models use a splined gear).

I will have to check the swingarm but all the others are ok. I had the headstay off to check cams and such, it is tight. Didn't see any cracks anywhere on frame.

I've had the carb apart several times, everthing is spotless with new pilot and main jet.

New Update:

I just tested the pickup coil, cdi and ignition coil. Pickup and cdi test within spec, not so much on the ignition coil. While testing the primary coil resistance it came in right at the high end of spec. But the secondary coil resistance does not give a consistant reading and sometimes not at all. So I figure there is a short of some sort between the coil and the end of the plug wire.

A new coil should fix my problem I hope. I will borrow my friends good coil off his bike and test it on mine before I buy one.

Any thoughts?

Alright finally some prgress! I borrowed my friends' coil and bolted it up. Bike started up quickly and seems much better on the stand so far. Hard starting went away, no more having to give it throttle. Vibration is down and powerband is much smoother and more back to normal. Now I will have to test ride to make sure.

I have read about the Hayabusa/ R1/ R6 coils and I am going to end up getting some of those. They are cheaper than buying a new OE one. Of course they are used on ebay, but if I buy a set of 4 with the wire harness I'm sure I'll manage to have at least one good one for a long while.

Checked out the clutch all is good and well within spec on every plate. Nothing worn or broken. I was thinking maybe something in there was causing vibration but no.

Put on a R6 coil today it runs better (on the stand) than mine but seems the same as my friends coil I tried.

With the seat off I could hear a clicking sound like the slide possibly moving around at a slight throttle opening probably 1/8th throttle. Hmmm is this normal? Probably not huh?

Hmmm is this normal? Probably not huh?
Yes it is.

Oh cool that is good news.

I'm wondering if I should buy a newer carb and just hope for the best....

How much play front to back should there be with the slide? I was curious after hearing the noise and with everything still installed and just the top cap off there is about an 1/8th inch of play. The carb body looks fine where the wheels roll, maybe the wheels wore out. Could this cause a lean condition?

.125"? Sounds like a lot. Is the slide moving in the rollers, the rollers moving in the slide, or both?

Overall, the slide itself shouldn't move too much; the vacuum release plate is supposed to chuckle back and forth some, but not so much the slide. If the plate and seal are OK, the slide shouldn't cause too much trouble directly, but it could cause the needle jet to wear, and that can become an issue.

The slide and wheels are tight together. But the wheels move back and forth inside the carb body front to back, like the wheels are too small or worn. It's hard to measure as the carb is on the bike right now but I was just guessing with .125"

I put the needle clip on the bottom slot today and it runs much better. I had never gone that far down, two slots up is the most I had tried before. I just don't see why I would have to be on the bottom slot. Seems awfully rich considering I am also using the JD Blue needle that is a richer needle than stock already

Ok here is the real deal and when this whole issue started.

I used to get a slow leak out of the overflow tube on the carb, found out the Oring on the seat was bad and letting fuel slowly leak by and raise the fuel level in the bowl slightly. So I replaced the Oring along with the seals in the petcock and the Orings on the brass inlet on the carb. Could it be that the little extra fuel in the bowl made my jetting richer than it should have been?

I used to have a FMF Ti4 muffler (race style muffler) and ran a 45 pilot with Blue JD needle on clip 4 and a 170 main.

I know have a Q4 muffler and put the stock 42 pilot back in for easier hot starts, Blue JD needle on clip 7 and a 170 main.

The issue started when I still had the Ti4 but just after I replaced all the seals and orings. The petcock flows normal.

I used to get a slow leak out of the overflow tube on the carb, found out the Oring on the seat was bad and letting fuel slowly leak by and raise the fuel level in the bowl slightly. ... Could it be that the little extra fuel in the bowl made my jetting richer than it should have been?

Of course.

Well I bought a carb rebuild kit that will be here soon. Comes with new needle jet and seals, etc. so maybe that will help out. We'll see.

Any chance the valve springs could be causing this? Instant rev + vibration at small throttle openings all the way up to full throttle?

I rebuilt the top end a little over a year ago but the bike has less than 20 hours since then. I did not change out anything on the head as everything checked out well within specs including the valves, valve seats and valve springs. Can the springs just go out all of a sudden? I wouldn't think so but maybe some others have experienced this....

Well I was pretty sure I had my cam timing right, but after looking at it again for the upteenth time lately it got me thinking. The intake seems it may be a tooth off. I did move it one tooth before and then the right mark is higher than the left mark, opposite of now but not as much of a difference in height as now. I did not run the bike the other way, only as pictured and have been having issues. 13 pins between top marks right now, how many should there be?

Should it be rotated one tooth you think? Intake is stock, Exhaust is Hotcam, timing chain is new and nice and tight, tensioner tests good.



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