Ok so I bought a 2000 polaris xc sp 600 ves and had a few minor problems that I fixed. I put a 136x1.5 track on it and took it up north first of the year. Thing rode great had some low to mid range bog (20-30mph) brought it back and had some bad flooding in the motor so I had the carbs and pump rebuilt. Now it backfires or coughs at idle and had no power. Put new plugs in it and it would not even start. Now I need fill choke to start and run it but still no power. 95lbs of compression across the board. Rebuilt motor and no difference. Any ideas?