Graunchy grindy J1

[Al]

1981 Z1000 J1 with standard frame (rubber mounted front) forks wheels swingarm cycle parts etc etc.

Between 4250 and 4750 (5000) RPM in any gear there is a hideous grindy vibration from the engine.

Its been there for three + years since i bought the bike.

It was there at 1000cc and is still there at 1166cc.

It now has high comp pistons, different barrels, different head, new camchain, new clutch plates / springs, new 630 chain, new rear sprocket, different alternator winding and rotor,

There is a little play and end float in the clutch basket but the drive gear mesh doesnt seem too bad.

Engines been apart twice and nothing found on inspection by myself and others. Although the crank hasnt been measured!!!!!

Crank looks very good visually and no detectable roughness in gearbox bearings or output shaft / final drive sprocket bearing that can be detected on the bench.

Is it possible or likely the crank might be out of alignment??
It hasnt been welded and has the 17mm pins

It hasnt gotten any worse or better during all its transformations and has done good mileage and two drag meets, couple of trips to Europe and been thrashed mercilessly by others during this time.

It has definately been dropped on the right hand side at some point and it has had a catastrophic failure of the final drive sprocket locking mechanism. But as far as i'm concerned this has all been replaced or engineered out now.

Any thoughts before i take it apart this winter.


AL

[Pigford]

Rotor/alternator

My Black Z1000 used to make a horrid buzzing/zzzzzzzzzzz noise at mid revs...... With variable pitch

One day I noticed it was bad..... low on petrol so went to get a tank of fuel - when I rode off from garage the noise had reduced dramatically

Turned out the tank was just touching the frame - and vibrating - when empty the resonance was in harmony & echo'd more thru the tank

Bit of old inner tube under the tank - SORTED Zorded

[Bruce Sexton]

Zorded. One of my work collegues had a similar thing last year on his Yam Fazer (i know not a zed) and spent hours tring to locate the problem. In the end a new chain, sproket set and cush drive bearing solved the problem. Maybe worth a look if nothing else solves it.

Bruce

[Al]

Thanks chaps for taking the time to reply.

It has a new (old bought from Pasc in perfect condition) rotor done up FT.
It also has a new chain and has had two new rear sprockets making three in three years. It has a different back wheel and new wheel and hub bearings also.

I am 100% certain that the vibration is coming from the motor.

Curiously; the day before yesterday i swopped bikes with my friend who has a tuned fazer. He didnt comment on the vibration because he was too busy wringing its neck, but i did notice grindy-ness from his and also that the dash panel / parcel shelf thing round the inside of the front fairing was the dominant and most annoying sound in his little orchestra of noises.

The tank is clear of the frame because i lifted it up 1/4 inch for it to clear the coils. Good thought that but the graunching is coupled to a very slight reticence to 'rev through' at that point.

Everywhere else in the rev range its like a big electric motor or as my friend described it a giant elastic band that you just keep winding and winding.



AL

[hillbilly]

have you checked the windings arnt loose in the casing,i had one that the three screws came loose in,that was a similar sound.

[Al]

have you checked the windings arnt loose in the casing,i had one that the three screws came loose in,that was a similar sound.

Thanks hillbilly, its on its second rotor and stator in three years and both have been tight.

Took it out again today and its still very noticeable through the frame, footrests, clocks, mirrors etc etc etc.


AL

[Pigford]

Al. you sure the engine mounts are nice & tight

Is the exhaust clear of the frame - all round

[hillbilly]

is the starter gear free wheeling,and not stiff on mount.ya never know.

[Al]

Al. you sure the engine mounts are nice & tight

Is the exhaust clear of the frame - all round

Thanks Piggy, all are tight and exhaust is clear of frame etc.

Its been like it for three years and the engine has been out twice in that time. This is also another silencer and there has been significant work on the original four into one.

The only thing that is the same about this bike it seems from three years ago is the hideous vibration centred on 4500 RPM.

Ive heard people say that when the cranks bend its a very uncomfortable feeling. My description is also vague which has led me to that conclusion, rightly or wrongly if you see what i mean.

Will take it a part over winter as planned. Its a relatively minor thing that i can drive round but stuff like that annoys me and i want to find out why.


AL

[Al]

is the starter gear free wheeling,and not stiff on mount.ya never know.

Thanks again hillbilly but sadly its in perfect working order.

The damper is also sized correctly to give a little drag to stop it clattering on the end of the shaft. Its the second damper too. First one was good but not perfect. There is no sign of fretting on the bearing track either, which suggests to me that the thing has never been left baggy as such.


AL

[hillbilly]

does it do it in neutral gear,or just while under load.

[Al]

does it do it in neutral gear,or just while under load.

Thats me off next doors' Christmas card list then. Sunday afternoon.

Sitting on it on side stand and revving it through gives this.

Idle; no vibes in footrests and chassis

1000rpm nothing
2000rpm nothing
3000rpm high frequency vibes
4000rpm more intense high frequency vibes
5000rpm no vibes
6000rpm no vibes
7000rpm mild vibration
8000rpm mild vibration
9000rpm bottled out!

That said; even though the transmission is unloaded so is the motor.
I dont think its that fair a test really.

What was youre thought here hillbilly?
Were you thinking gears or gearbox?

In the final drive the only original part is the front sprocket which looks very good still.
It has new swing arm bearings and sleeve.
Frame was motolinered three years ago.
Sprockets and wheels are in good alignment.

Any up date on the Turbo 1R???????????


AL

[hillbilly]

i was thinking some sort of gearbox problem,wear and tear on teeth,bearing housing,my guess is its the gearbox,but thats just mine.hope you tell us all different.
as for the turbo z1r,im waiting for all my mother and fathers posesions to be sold,ie jewelry,antiques,then there house.should get a fare amount.then its open season on the bike builds.

[Al]

I'll let you know when its been apart if anything shows up. Could be a while though.

Good luck with the Turbo1R if you do go through with it hillbilly.


AL

[AndyZ1R]

It`s not your false teeth rattling is it? If Mike rode it then he`d experience the same problem. Maybe you need a young lardy boy (or lady boy?!) to test it, the extra weight could dampen out the vibrations.