KZ1000 odd vibration / judder @ 2200 rpm

I have a 1979 KZ 1000 and it has an odd vibration / judder at 2200 - 2500 rpm, it feels like engineas it happens in all gears at that rpm, possible thought is clutch judder maybe, any ideas anyone and how to fix it

cheers

Tune up/clean carbs.............
Check motor mount bolts.........

engine bolts good an tight, just had the carbs apart and are totaly clean, bike runs smooth as anything

If not already done, would assure valve clearances are within specs, and that the timing advancer is properly functioning.

Good Fortune!

I've been experiencing bad engine vibration for ages now.....looks as though it's a dud valve. I've pulled the plug leads off each cylinder to see if it makes a difference to the motor, and No 2 always does nothing.....it's almost dead.

Mind you, when I install a brand new plug, it runs great and smooth for about 80 mile, then starts playing up again. Still has heaps of power though.

I've doing a valve clearance check this week.

PRM068 wrote: ...when I install a brand new plug, it runs great and smooth for about 80 mile, then starts playing up again....

A too high fuel level in the float bowl can be one reason why a good-firing new spark plug quickly fouls out.

Could perform the clear tube test to determine whether fuel level is within specs.

The clear tube test will also indicate whether a float valve is leaking, because the level just keeps rising regardless of the float valve being supposedly closed.

A seriously leaking float valve is another possible reason why a good-firing new spark plug quickly fouls out, due to overly-rich mixture being furnished from the carb.

Good Fortune!

Like i said the engine is running as smooth as anything, perfect in fact so not valves or anything like that, it feels more like transmission

Hey Patton,

I've been meaning to get around to doing that tube test, but was wondering if you actually need the proper "official" kawasaki stuff to do it, or can i just grab any old bit of tube ?

I looked it up in the manual - just haven't had time yet. When i pulled the carbs out, I pulled both 1 and 2 apart and compared them.....just quickly. The float level for both seemed about the same, but there's that word...."seemed".

And WOODSY....that's the thing.....my engine runs pretty smooth also. It's only when you're out on the road doing reasonable speed that you really notice it.

Peter.

Any clear tube that fits snugly into the drain hole will suffice.
An appropriately sized clear plastic tube may be "self-threaded" into the drain hole.
Slight minimal leakage doesn't invalidate the test.





So long as the fuel level is within specs per the clear tube test, it really doesn't matter what the dry-measured float height happens to be when the carbs are disassembled upside-down on the workbench.

Where the fuel level is for whatever reason completely screwed up, the dry measured float height may be first adjusted to achieve a hopefully acceptable starting position for the clear tube test.

Good Fortune!