The Fix Report
Ok all I talked to Shawn today and he designed this kit, he will also be posting some additional information as well.
Shawn explained that the 2010 update has a big piston clearence concern which is about 6-8 thousand and that the actual spec is 3.9 to 5.9. This was done because of the wear issue on all of the burn downs where the thrust side always seems to look good but the exhaust side wears a real shine like grove just below the crown line.
Apparently this is where all of the wear takes place and this is the reason for this fix kit. The pistons were developed to Shawns specs, Shawn has been involved in building t 2 strokes for a long time and based on his knowledge he knew that the polaris piston is to short and rocks or teeters at the top of the compression stroke and that is where the wear ring is on the exhasut side just below the crown.
So he had the new piston made about a 1/4 inch longer and slightly bigger, the crown to the piston has been lenghtened and that is why the shim makes up the difference for the heigght and does not change the timing or the stroke of the actual engine, this also reduces the piston rocking or twisting motion. The cylinders need to be honed out to fit the new pistons which come with the wiseco's special coating to help reduce wear.
This kit does make about 5 hp more and produce about 100 more rpm at the top of the power ban since the pictons are 40 grams lighter then the stock pistons. All of this information is just what I can recall from our phone conversation for now. This company has had good luck in returning these sleds back to the orignal 2008 tune from polaris when this kit is installed and they claim about 150 hp on the dyno with out a power commander and with everything else stock.
