MCB Polaris 2007, 2008, 2009, 2010 700 CFI Durability & Performance Top End Dual Ring Piston Kit 700 Dragon, 700 IQ, Dragon RMK 700, 700 Switchback, 700 RMK

You must specify your exact year make and model when ordering.
Why does my sled need these upgraded pistons?
Some of the 2007-2010 CFI’s suffer from considerably shorter top end life, as compared to the 1998-2005 orignal Liberty motor.
Much like the 800 CFI’s the 700 CFI piston stability is marginal. Consequently, ring lands and skirts are compromised resulting in the shortened life. Understandably, the 700’s suffer from the same QC issues as the 800’s. In particular, tolerance stacking. This is when the OEM set tolerance ranges that in themselves are reasonable but when all are are at the extreme end of the range they have created a significantly weaker product. (Piston on the small end, cylinder bore, taper or roundness at the large end)
The MCB Performance 700 CFI piston kit addresses these issues in multiple ways.
First we use a two ring piston design as compared the early 07-08 OEM single ring designs. Second, we use only genuine Italian forgings that have a highly proprietary material. This allows the piston to be operated in all environments and the expansion very closely matches the castings the OEM uses.
Third, the cam profile addresses the potential for the “large end spec”. In addition the skirt profile is designed to have significantly increased bore stability.
Fourth, Because all these are fully CNC’d externally AND internally they are balanced to a much greater degree thereby providing a dramatically smoother & consequently faster revving engine. Our pistons weight 356 grams, stock Polaris weight 400 grams.
Customers who have used these consistently have the same comment “It’s a completely different engine, sewing machine smooth, and feels like additional HP!” In several cases customers have had to add 2-3 grams of clutch weight to keep the machine from over-revving. This is a snowmobiler tuners dream (more weight and still able to spin max HP RPM = faster acceleration and top speed)
On any two-stroke engine we cannot stress enough the importance of bore sizing and condition. Skirt clearance, bore taper and roundness on any two stroke motor, but especially on these later Polaris 700cc engines is critical. We strongly suggest replacing your cylinders if there is ANY doubt as to the dimensions or condition.