help with compression test on klr 650

[ngj874]

I did a compression test on my 99 klr with 28000km on the clock. The tester said 300 kpa and the manual says it must be between 530 & 855 kpa. I read up that the bike has some kind of automatic decompression valve. How can i do a proper compression test with the decompression valve not interrupting?

 

[Fugly]

 

[GreenMachine]

 

[GreenMachine]

 

[lecap]

 

[ngj874]

 

[Fugly]