Right after the March 2006 issue of SnowTech went to press, Polaris announced they were NOT going to be building any new big block (755 & 900) two-stroke twins for the 2007 model year. This announcement was made right about the first week of March, so this word pretty much didn’t hit any of the Spring magazines, anywhere.
So, what’s up with this? Word on the street was that Polaris had designed a new engine mounting system to better dampen the vibrations of the big block mills, and that this new engine mounting had failed the bulkhead during late season durability testing. At that date, Polaris needed to decide if they should build the 2007 models using the previous engine mounting (with the vibes that some consumers were complaining about) or to not build them at all. There simply wasn’t time to fix the â€œnewâ€ mounts for the 2007 seasonâ€¦..and there likely were a good number of 2006 units in existing inventory.
Officially, Polaris issued a statement in regards to there not being any big block mills in their 2007 line-up. On March 14, 2006, Polaris stated, â€œAbout two weeks ago, Polaris made the decision to suspend production of the engine platform known as the 755 and 866 Big Block (the block for the 900 engine) until further notice.
For 2007, the new RAW RMK chassis boasts a number of enhancements – and is more rigid to allow for the great weight reductions the sled boasts. This added rigidity transmits engine vibration at a greater level than our previous RMK chassis. The 2007 RMK 900 motor mount system was redesigned to address this vibration, however, in the final stages of validation, the motor mount system failed.
As part of Polaris’ quality initiative, Polaris refuses to put this product into the field in this configuration. As a result, the 2007 RMK 900 has been suspended from model year 2007 production.â€
So, at least for now, you can not buy a 2007 Polaris with a big block 755 or 866 engine. This includes RMKs, Switchbacks, and Classic models.
What about the 700 engine in the Dragon models? This â€œnewâ€ 700 twin for 2007 is an all-new engine based on the 600 H.O., and is NOT the big block 755 of 2006. One pull of the trigger and you’ll quickly realize this new engine is a revver and a screamer, not the lugger and grunter 755 of 2006.