Stihl ms311 compression question

[yamaracer]

hey guys,
new member but have been lurking/reading on here for a while.
i own a Stihl ms170, Husqvarna 55 rancher and just bought (used) a Stihl ms311 w/a 25" bar.
the 2nd day of owning the ms311 i started blocking 8 cords worth of timber that had been dropped earlier...
the saw(ms311) runs great and did a good job but the compression seems a lot less than the Husky 55 rancher.
it has the decompression valve on it which i do not use as it's so easy to start w/o it, the saw idles fine, is clean on the bottom, revs as it should and is clean on the top end. 
i had the muffler off today to replace the gasket as it had an exhaust leak and took the opportunity to look at the piston and cylinder while it was off.  the piston looks fine(no scoring) the cylinder still has the cross hatch marks on it...

what are you guy's thoughts on the compression??

also, have any of you put a ms391 jug & piston on the ms311 or have any thoughts on that?

thanks guys!

[DelawhereJoe]

Have you done a compression test on it or are you going by ease of pull ? I have an old 024 av that takes more force to pull then a new 362 c-m.

[yamaracer]

i have not done a compression test on it, like you said, it just seems much easier to pull than the Husky.

[Texas-Jim]

Lot of factors beside compression determine the amount of force needed to pull the rope. Even the size of the rope carrier, a 1/2 smaller is a lot easier to pull. If your concerned you can do a compression test. Iv been a stihl wrench a long time and iv never owned or used a compression tester.

[yamaracer]

thanks guys for the responses, i guess i was just a little skittish with it being a used saw...
runs, sounds and cuts great, i'll stop being paranoid about little stuff.
btw, is the muffler mod worth doing to the ms311?

[yamaracer]

quick update on my saw.
i ordered a compression release valve plug for the saw jsut to see if there would be any differences...
removed comp valve, installed the plug and fired her up.  it was a little harder to pull/start but started quicker than with the comp valve.  the saw sounded better and went through the wood better as well!!
i don't foresee the comp release valve going back in!