Sticky valve ??

[paddle]

Hi guys just did a compression test on my 750m engine after discovering its true miles 72k.i got 115psi on 1 2 3 cylinders and 20 on number 4 as the bike has not run for 5 years could this be a gumned corroded valve seat ?? Should I run it to seeif if it mproves the other 3 readings are very close together 

Thanks 

[Captain Chaos]

check the valve clearances on cil 4.

[paddle]

Ok thanks I think the 750m engine is bucket and shim will pop the cover off and look 

Thanks 

[Captain Chaos]

rocker and shim.

[FJD]

I would try to get it running first - rusty valve seats maybe

[paddle]

That's what I'm going to do I think