Xj650 KO model UK bike 27k on engine ?

Hi
Started to check compression today low 1982 KO engine 650 i8xj
across the 4 cylinders here are two photos max an min psi as it has be lying for a year or two any ideas it turns over fine set rings do it and valves cleaned and regrind
Mike

 

If it has been sitting it may have stuck rings etc. that need some oil or run time to get the compression back up.

Have you checked the valve shims? If any are out of spec (tight) then it can affect your readings. I would start there before tearing anything down. 27k miles or m's is very low for these motors and I wouldn't expect anything serious to be wrong unless abused.

 

Try the acetone automatic transmission fluid 50/50 mix a tiny amount in each cylinder to ease off the piston rings.

 

Ah thank you I have used diesel in the past a spoon full per pot
Will let you know
Mike

 

Hi happy new yeart all
Did as Franz said left it a while as my Sealy heater was not working anyway
Just tried the compression test to find
Pressure
No1 75psi. No2 100 psi

No3 125psi. No4 115psi

Second photo teaspoon off engine oil down no 1 cyclinder 215 psi

Psi gauge is the push on to the plug hole not screwed in type which I have
so may have to pop the head of valve seals
Mike

 

Did you check your valve clearances as jayrodoh advised?

 

Opps Ah no let me do that senior moment

 

That's good, you're looking for an increase which indicates it is most likely not a valve issue. You may just have some stuck rings that will break free/seal up once run for a bit.

If the third picture is your actual set, the hose and brass adapters are for the spark plug threads. Nothing wrong with the rubber tip test if you can hold it firmly in place while turning motor over with the throttle held wide open.

 

Thank you no carbs on getting soda blasted