03 kx500 compression?

[Pointhunter75]

How much compression should my 03 have?  And can I test it with only the carb on it?  No air box/ filter. Hasn't been Crunk since 2011. I drained the carb but still just now cleaned it. Also I need an air filter.  What is the best these days?  Been out of the game.  I liked twin air back in the day. . Ok I put my old mx boots on and kicked it till I was tired... only got 125 psi. I'm 48 years old and out of shape with bony legs lol.  When I bought the bike in 2011 it was nothing like the ragged looking 86 I test rode with hardly any plastics.  That thing would stand up in 5th gear at 8th throttle...I had this one jetted and it helped a little bit was still nothing like that old ragged 86. I wonder if the crank seal is bad or maybe just needs a rebuild after this compression check?  Opinions please.
Edit
Apparently this is not the place to get common info on these bikes.  Can't believe not one reply. 

[Bengt Weil]

According to the '88 Kawasaki Service Manual for the KX500, cylinder Compression (usable range) is 105-164psi.  The supplemental manual for '90-'03 does not have any updated information, so the same usable range should apply. 

Based on your compression findings, it should be OK, though maybe not optimum.  I would definitely do a leak down test to verify there are no air leaks (crank seals, etc) before running it hard.

As for the air filter, most anything is good now days.  On my 500, I us a No Toil filter and associated cleaning system.

I would imagine it would be best to remove the top end, make sure there are no obvious issues with the cylinder plating, clean the power valves, check big end rod bearing and reed petals and re-ring or replace the piston and small end bearing if clearances warrant it.  Much better safe than sorry...  Good luck!