Messing up the compression test? Help!

[ProspectMarblesMT]

I have an 02 suzuki katana that was donated wrecked in the front end to our clubhouse. its been sitting since wrecked which I assume is probably about 2 to 3 years.I tried running a compression test on it and I keep getting weird readings.some two cylinders are in the sixties two cylinders are in the 30's. but if I keep repeating the test on the same cylinder it'll go up about 20 psi the throttle is wide open and all the spark plugs are removed what am I doing wrong? are there vacuum lines that need to be hooked up?

[IanDMacDonald]

I have an 02 suzuki katana that was donated wrecked in the front end to our clubhouse. its been sitting since wrecked which I assume is probably about 2 to 3 years.I tried running a compression test on it and I keep getting weird readings.some two cylinders are in the sixties two cylinders are in the 30's. but if I keep repeating the test on the same cylinder it'll go up about 20 psi the throttle is wide open and all the spark plugs are removed what am I doing wrong? are there vacuum lines that need to be hooked up?

Howdy- Having all the plugs out, and throttle all the way open are indeed correct. Throw a spoonful of oil down each spark plug hole to see if your compression raises. If yes, follow-up with a leak-down test. Me personally, on a bike sitting that long un-fogged, I'd give it a MMO treatment, and try and get it running. After that, change the oil and run a compression test again. My guess is that the rings are sticky.

Worst-case: bent valves or worn rings.

[ProspectMarblesMT]

Howdy- Having all the plugs out, and throttle all the way open are indeed correct. Throw a spoonful of oil down each spark plug hole to see if your compression raises. If yes, follow-up with a leak-down test. Me personally, on a bike sitting that long un-fogged, I'd give it a MMO treatment, and try and get it running. After that, change the oil and run a compression test again. My guess is that the rings are sticky.

Worst-case: bent valves or worn rings.

Now oil... the spoon full is coming from the gasket under the header. Is that just the gasket then or is it something more

[shpielers]

Most likely just the gasket, but if the bike was wrecked, there might be a crack or warp. Leak down testers can usually be "rented" for free from auto stores, might give you a bit more info.

[IanDMacDonald]

Now oil... the spoon full is coming from the gasket under the header. Is that just the gasket then or is it something more

Under the cylinder head, or the header pipes? Could be loose header bolts (check the torque), or as stated above, a nice cylinder head crack, which would most definitely have an effect on compression. Either way, you just found your leak.

If your head bolts are tight, go ahead and pull the head, and either it's cracked, or the gasket is blown.

[ProspectMarblesMT]

Under the cylinder head, or the header pipes? Could be loose header bolts (check the torque), or as stated above, a nice cylinder head crack, which would most definitely have an effect on compression. Either way, you just found your leak.

If your head bolts are tight, go ahead and pull the head, and either it's cracked, or the gasket is blown.

thanks for all your help on point in the head now. and I meant header pipes