He's off by .5, if you bored 1mm over that would put the bore size 0.40 over because stock bore is ~72mm, 0.020 over= ~72.5mm, 0.040 over= ~73mm so that makes 1mm over be equal to 0.040 over not 0.050 over. Just don't let him screw up the bore size that would be bad

 

i wish i would have seen this tread a few weeks ago... cause like Hoede... i'm a new atv owner.
I have a 97 trailblazer and had it given to me also... but it also had the compression at 60lbs and
wouldnt start. So... not knowing and wanting to know the hard way .... i pulled the engine out of
the frame and have it on the shop table... Having just got laid off from work... i'm looking for
the cheapest way to hon it and replace the piston and rings and gasket... so going with a wsm kit
and having it honed sounds like a safe but trifty way....
(i haven't looked into it.... but i'm assuming the wsm kit is cheaper then buying stock...
cause i've been hearing that you should go stock for Polaris in particular)

BTW... were would one fine an exploded diagram for this model? You can't get it off the polaris
web if its older then 2000

 

You can go to Partsland.com to get breakdowns of any model. The top end is really easy to do. If you are not going to do any big mods then stock would be ok and the wsm kit is good also. Either way will work fine. Get a ball hone from napa and go with a stock size piston and rings. You will also need a cylinder gasket. That is pretty much all you need. Just make sure you dont hone it to much and before you put it together the cylinder is perfectly clean.