headshake woes... mechanic problem

[mysterious_rider]

Hello guys Ive owned my zzr600 (1995) for over two years now, the trouble I'm having is after the first year of ownership ive been getting savage headshake...

Around corners it will buck about, and around roundabouts if i get it really low rather than countersteer, it'll try and TURN IN to the corner and it will drop like a stone.

It's gradually been getting worse and it's at a point where I want to start replacing things to sort it out, It was so beautiful to ride when I first got her!

The only things that I can think of;

Tyres, the rear is relatively new, but the front is low, none of my tyres are squared off though! Pirelli tyres.

Suspension, can fork oil go bad? The front is fairly soft.

Rear suspension, is constantly wet on the chrome part. My assumption is it's leaking, but i Haven't lost any damping from what i can tell..

Tyre pressures, I used to run 37psi front+rear, but I cannot do this anymore as the headshake is so bad. If I hit 100 in a straight line I'm fighting the shake. I run at 35 and its a lot better, but a problem in corners...

What would your first checks be?

I also tried adjusting the suspension, raising lowering the front...rear... Made it a lot worse.


Any help would be great...
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KAWASAKIIIII

[davebike]

Classic tyre problem worn front + good rear = wobbles at lower speeds
Worn rear good front gives similar but at higher speeds

Change the tyre before anything else
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Dave
NC750Xdct + others at work !
davebike1@gmail.com

[Robby]

It's a 20 year old bike, just about anything could be worn out. Sounds like something is seriously wrong.

Worn tyres can cause all manner of handling problems. Yours sound more extreme that I would expect, but I don't know how worn your tyres are.

The rear shock is worrying. Do a bounce test to see if the damping works, you probably have some damping left but not enough to be effective.

Any chassis bearing could be worn out.

[Hetzer]

Headstock bearings knackered?
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"There's the horizon! Ride hard, ride fast and cut down all who stand in your way!"

[mysterious_rider]

Fitted a new maxxis front. And put 41psi in the rear... completely sorted it now. .. unbelievable had this problem for almost a year! Cheers lads.
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KAWASAKIIIII

[andys675]

fork oil does need replacing at some point, my suspension guru recommends changing it at first service as the forks go through a bedding in period as much as the engine

the rear shock is leaking, it may be ok now but you're pumping the remaining oil out of it every time you ride, it will run out of oil eventually, a rebuild from someone like revs racing will be the cheapest option above buying a used shock
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Some people feel the rain, others just get wet.