Fine Vibration

I was driving the 850 this evening and it seemed to gradually start to vibrate more than normal.

The motor pulls strong and it tracks true enough. But, when driving its almost like driving over fine washboard, especially at slower speeds.

The chain needs to be adjusted a little bit tighter but I don't think that's the issue.

Could it be isolastics? What are the symptoms of too loose & too tight isolastics.
Cheers!
Stephen

One thing i can grantee Loosely Worn iso rubbers just make for smoother sailing, so unless yours some how wore in tighter, look beyond iso mounts them selves.

Cracked-tweaked head steady, loose coil on tank or frame, cracked tank mount ears, cracked front cradle, object logged in iso seam, crank shaft finally giving up, electrical resonant grimlein, primary chain going away...?

Check engine and gearbox bolts. Usually fine vibes tell you that the engine is not tight in the cradle. The isos cannot cope with a lose engine....

Is your chain worn? How are the sprockets? Is the primary chain too tight? Do you have a belt drive and the vibes get worse after running a bit. If this is the case a little hole drilling in the case out may be in order. RGM clutch hub swell but usually effect clutch action.

Has this motor been out of the frame? Things tend to settle in many ways after a run or two. Either way, you better check. Particularly check the one on the bottom at the front of the gearbox cradle. That's the one that got me.

Do a search for Iso adjustments. There is a link somewhere that tell the different characteristic at different rpm's. There is another that tells how to read the circular vibration patterns in your mirrors.

http://www.captain.norton.clara.net/cnn ... tml#2.33.1

If you are knocking at 60's door, doing 70 down the highway and your hand aren't going numb, you are good to go, very very good to go.

Thanks Gang. Will check all leads.

Motor is newly rebuilt so a check of all mountings is Step A.
Stephen

I bet the rear Iso bolt is rattling in the tube, plus the threads/ tube are compressable, resulting in No side clearance...Check all around the washers...maby they could be out of square. I may be completly wrong... But because i have a beef with the whole idea of bits of rubber trying the stop you eye balls from falling out! i blaim them for everything :!:

Yup ,had same symptoms from loosened bolts, the 2 upper subframe ones that hold the motor bottom end into the subframe cradle.