Cure the high idle and lean midrange of any Ski-doo REV 500ss, 600 HO, 800 HO, XP 600 or XP 800 carbed sleds with this kit. 2016 Updated with more shims, this kit now contains four .020" carburetor needle shims, four .010" carburetor needle shims, and two new pilot jets to cure the hanging high idle and lean midrange condition in most Xp carbed sleds. We install this in all stock and modified trail sleds. The stock 600's are shimmed with .010" shims. The stock 800's require are shimmed with .020" shims. Aftermarket Pipes and y-yipes and porting will usually require .020" to .030 " shims. This kit was designed and tested with stock or V-force reeds and from 0 to 4500 ft. altitude. The combination of shims now included in our kit allows shimming from .010" to .060". The kit comes with specific shim &jetting specs for both 600 & 800 Xp carbed sleds.