GPZ600R Enginer & Handling Issues - Any Suggestions?

Yes, I took a lap on my friend's 1986 600 Ninja. He was standing at
the apex of a slow hairpin corner and he threw a liter of water on me
as I went by because he thought I was riding his precious too hard.

But he retired the Kawasaki to street use and bought and FJ600 which
was more stable handling in the high speed Turn 8 at Willow Springs
where he could go 130 mph.

He just didn't want to try and ride the Ninja that fast. He had been
class champion in the 550cc class on his CB550 in the mid-1980's.

 

Hey! I've offered help to Dylan before, under totally anonymous
circumstance, and he was also polite and he thanked me for my help.

But, you always have to be a sanctimonious asshole.

What makes you and Dylan so different?

 

Reading more carefully, I see he did replace the
swingarm bearings already.

I guess the other interesting question is how the handling
problem began. Did it start suddenly, and if so, what changes
to the bike and riding events immediately preceded it ?

Any change of tires or bearings or other maintenance just
before the problem started would be strong suspects.

 

So? Goatse you have to understnadn something...if you don't have my
permission then you can't post anywhere. I mean for crying out loud I
told you to NOT go to sturgis and you stayed hom like the little
cowardly pedo that you are. So, I'll make it real simple for you. Get
off of usenet...NOW boy. Or I'll quiet paying your mother and she'll
just have to do the donkey show for free from now on.

 

Because TOG knows what an uneducated deviant you are.

 

Doh. 1984, actually.

 

Oh, one lap. Two years later. Qualifies you to pronounce on it, then.
Yes.

 

I'll bet S'mee's goatse ass that the problem is with those squirmy
dual tread compound BT45's...

 

shows what a nonriding fraud like you know...then again I've only
45,000 miles on BT45's. I couldn't possibly have a clue after riding
on them in pouring pacific north west rain, desert heat or highly
abrasive rocky mountain roads how they handle and behave. Oh no I
couldn't possible know more than a man who has never ridden a
motorcycle in his life and LIES about owning and riding motorcycles.
Tells us again why grumman fired you...something about not cleaning up
LEM 1 as I recall, you said it was womens work.

 

Crap in the carbs, choked air filter, cleaning rag left in the airbox/near
the intake. Were all four plugs sooty or just one?

Head bearings too tight/notched/dry can cause similar, as can poor
alignment.

 

Nonsense.

 

That's several votes for the head races so far.....

 

Point being though that problems don't just appear
by magic. Not always but very, very often, they can
be traced back to the most recent work done on a
bike.

So the question is whether the problem appeared
when the bike was put back on the road after working
on it or a longstanding problem that the owner gradually
became aware of or something that cropped up suddenly
with no recent work on the bike.

If a problem cropped up suddenly with no recent work
I'd worry a lot, but this is pretty uncommon.

Oddly, this type of information usually gets omitted from
problem reports.

 

We use BT45's on our training bikes, and we used them at my last place too.
Why?, they are a stable, tractable, predictable tyre that gives a compliant
ride and thus engenders confidence in our novice riders.

It may be the OP is noticing new tyres, and previously rode on a different
brand/profile tyre. It may be the OP is hanging on for grim death and the
bike doesn't like it. Providing the tyres were fitted the correct way round,
the pressures are OK, everything is in approximate alignment, then one of
the last things I'd look at would be the tyres.

I'd start at the front. No play in the front bearings. No play in the fork
bushing. Axle nut tightened. 'Bars free to move from side to side with no
notching and no play. Get a fishing weighing scale and check the turning
force required. It'll be in the manual somewhere.

Noving back, check the rear fork for play. It may be the bearings have
'seated' and need nipping up. Check for play in the rear wheel bearings and
suspension links.

Check the static and rider sag. You need sag. You also need controlled boing
in the suspension, so is it damped.

 

My ding-meter has just broken.

 

<G>

 

Well fer chrissakes! Just *look* at the tread pattern on those things!

Maybe it rains everyday where you ride, but to me, living in arid
central California, BT45's are *rain tires* with their deep water
channels and unsupported tread blocks.

Mix harder compound rubber in the center of the tread and softer
compound rubber on the sides, and ride on macadam that has been worn
by the passage of many car and truck tires, and you have a motorcycle
that's wiggly in a straight line.

The 600 Ninja was designed for sporty riding on billiard table smooth
surfaces and it needs *sportbike* tires with fewer water channels and
larger, supported tread blocks.

The absolute wiggliest tire I ever rode on was a Cheng-Shin universal
tread pattern.

The zig zag pattern had lots of water channels and tall unsupported
tread blocks that interacted with rain grooves and brushed concrete
and my girl friend complained that it made her nauseous to ride on the
back of the bike as the tread pattern tried to align itself with the
grooved pavement surface.

 

They're perfectly good touring tyres. I'll agree they wouldn't be my
first choice on a full-on sports bike, but they don't squirm like you
claim they do.

Try riding on them. You haven't. I, and other sin this thread, have.

Utter bollocks.

More utter bollocks. I rode my first one in 1984 and have ridden more
since, and you're talking shite.

No

<snip the usual antique reminiscence>

 

I live and work in Yorkshire. Yes, it rains. A lot.
I've used BT45's on trackdays too. A Honda Transalp with them, and a GS500.
Never had an issue with either bike at Cadwell. Well, other than sod all
straight line speed. Tyres are a personal thing. I prefer Continental tyres,
but have a pair of Pirelli Diablo Strada on my Bandit at the moment. They
were cheap, I was skint.

 

Krusty, to whom you are replying, is noted for trying to dispense his
own home-brewed wisdom.

Time was, a few years ago, newbies hung on his every word, believing
that they were worshipping at the feet of The Master.

Unfortunately his bluff has been well and truly called and the
succession of hysterical misinformation that drips from his keyboard is
properly refuted every time.

This has turned him into an embittered little man, which is why he
morphs his identity, in the hope that he can continue to deceive the
ignorant and credulous.