Compression Test?

[Never2L84Ridin]

Here's my situation. Prepared the bike for a compression test. With the engine warm & at running temp. did a dry test with the throttle open. #1 (80 psi), #2 (80 psi), #3 (45 psi), #4 (95 psi). The bike shows it has 26,000 miles. Should it be showing those kinds of #'s with that mileage? Could it be the valves or rings? Any info would be greatly appreciated. This kind of troubleshooting is new to me. Thanks in advance,
Kevin

[prometheus578]

With the engine warm & at running temp.

With compression numbers like that, I'm surprised that you were able to get it to run and warm up! Compression standard should be about 142 psi, (128psi minimum), with no more than 14 pounds pressure difference between the cylinders
.. you usin' some sort o' metric gauge?
But a better possability is that the rubber o-ring, where the threaded part goes into the plug hole, ist ferschimmelt and allowing pressure to leak past. With the hose screwed in, spray some soapy water around the fitting, and see if it bubbles when you crank.
If you really think the compression is bad, bring the cylinder up to top dead center(on the compression stroke) hook the gauge's air hose to an air compressor, and listen for leaks.
Hissing through the exhaust pipe, bad exhaust valves. Back through the carb, bad intakes. Hissing through the oil breather or the hole where you pour oil in, rings.
Or.. I think your gauge is loopy.

[prometheus578]

Hey, when was the last time you checked the valve adjustment? Valves too tight would tend to remain open, hence loss of pressure.
Carbon build-up, (from lugging the engine and not winding it up on the highway once in a while) can form on the valve faces preventing closure.

[Geezer]

Did you have the throttle open when you did this test? This is the most common mistake when doing a compression check.

If you did the test right, check the valves. If they're tight, then you found your problem and it's most likely time for a valve job.

Geezer

[Never2L84Ridin]

I forgot to mention that there is alot of noise on top side of the engine on the #3 & #4 side. Sounds like I need to check the valve adjustment, cam chain tensioner (hasn't been adjusted since i've had the bike). Is this the symptoms that is indicating valves?

[prometheus578]

Noise on the top would indicate loose valve clearance.(But valve's usually tend to get tighter as the valves seat themselves further up into the head.)
Noise up top would seem to indicate too much clearance hence loose valves. Combined with your low compression, would say that the valves aren't closing all the way. Either due to carbon build-up on the faces, or they might be bent or burnt. Hard to say without actually being there.
Did you check the O-ring on the compression fitting where it screws into the head for leaks?
If those compression readings are acurate, time to pop the cover and check valve clearances. A pressure test of each cylinder, as described above, would give more definative answers, provided that you have a compresser to supply the air.

[Never2L84Ridin]

I did not check for leaks from the o-ring. I will be doing that test to see if it is leaking. Another question is if it is carbon build-up, how do you go about getting the carbon off?

[prometheus578]

Hate to say it, (and someone correct me if I'm wrong), but pullin' off the head is the answer.
But let's not jump to that yet(though it's really not that big of a deal)
Let's get clean readings from the other tests, first
When I had a bent valve, I decided to clown around a bit. (cylinder had about 45 lbs of compression) Brought piston to TDC on the compression stroke(Both valves closed) and stuck a really bright flashlight in the plughole.(Was cyl #1)
Anyway... with the pipes off, was able to look in the exhaust port and see light coming from around the bad exhaust valve.
I already knew it was bent. Low compression, and the valve clearance was way off,,, about .035 or so,meaning valve still open.
Redo your compression checks, pressurize the cylinder if you have the equipment, and then check the valve clearances.