Reclentley bought this bike its a 81 Kawasaki KZ550 ltd and i replace the battery because it wouldn't hold a charge and now it shuts off at 5000/6000 RPM's..... i took the carbs off and they look clean.... i mean relay clean... the petcock was in good shape as well seems like gas flows well.... in addition i will randomly hear a raddle / knock sound.... and whit smoke.... never at the same rpm's or same time. any advice with eathor problems or if there connected?

 

White smoke? Does it have the aroma of engine coolant? Maybe a bad head gasket that pulls in a sip of coolant at that rpm? Just guessing here...

I have a snowmobile that acts similar. Need to tear into it.

Welcome to the forum. Hope we can help you find the problem.

 

no its an air cooled bike i think it might be oil...... the cooling fins on the cyl on the left side of the bike are chipped like it was dropped hard at some point.

 

Could be an ignition problem. If yours is a KZ550A1 it might have points (contact breaker) ignition. If that's not set up properly then it will be a right pig of a thing. If it's a different variant then if could have electronic ignition but will still have mechanical advance.
It would help to know what your spark plugs look like when they cut out. You'll need to take it for a ride and then wind it up till it cuts out and then pull a plug out straight away. Take a picture of the business end of the plug, or make careful note of it's colour and condition, and let us know what you find.

 

Ok, just looked it up, the '81 KZ550 LTD is a C2 so it should be electronic ignition.

 

yea sorry its is a c2 ...... i orderd new spark plug wires and have new spark plugs ready to go in when the wires get here i was thinking they might be a problem.... the casing is cut up on two of them.... and dident want to put the new plugs in till i got the new wires.

 

You're lucky. I used to own an '81 Z550G1 (GT550) and still have the manual for it.
I scanned the fault finding guide and regular maintenance chart into this PDF for you.

LINK

It's 16MB, just so you know.

 

verry cool thanks!

 

If you find you need something specific (from the manual) let me know. It's not little so scanning the whole thing is a bit much, but I'll see what I can do if you have some idea what you're after.

 

ok very cool i appreciate it!