Compresion Test

[Muddychris]

Hi

I have a leaky valve stem oil seal which i'm in the process of sorting. Bike smokes a bit on start up and there is a bit of oil dribbling down the front of no2 exhaust port.

Spoke to a bike engineer this morning who put the fear of god into me, said that the piston rings were likely to be knackered also the pistons would be knackered as would the bore. Ended up with a figure of ?452 + labour all in including the rebore and and big bore kit fitted.

I dont claim to know too much about engines and my project ELR is on a budget which this on top of would blow the budget out of the water and cause me loads of grief from the wife.

Spent the afternoon fitting a nice polished swing arm in an R1 this afternoon so didn't get as much done as i would have liked. Actually i didn't do any of planed jobs but i did do a compression test.

As you sit on the bike working left to right my compressions are

170 150 155 165

Are these within tolerance?
With my limited knowledge i wouldn't have thought that these figures warranted a total strip down, but i would like the collective's opinion.

Regards

Chris

[big green bus]

there should be no more than 14 between any two cylinders but i would not worry about yours, just do your stem seals and grind your valves in, do your shims etc. if you wanted to rebore it i would not bother with standard kawasaki set up. go for a 1170 wiseco ?275 it is much better and cheaper. i am sure someone will say "stay standard ",but you need deep pockets if you do,

[london calling]

Quite right Steve,but Chris can't go out to 1170 with his existing block.
73mm maximum with the 998 block.
Like you say though Steve,do the valve seals,re-grind valves,shims,etc and see what you've got then

[Pigford]

None-the-less, if you do go for a rebore, use Wiseco, whatever size.