First of all, thanks for a great magazine! You are the only sled mag I trust for honest, real world information. The 2006 Polaris RMK 700 (755cc) 144 x 2 looks like a great off-trail set-up. Add C&A Pro skis, SLP can and air filter and weight is within a cheeseburger of the Renegade. But, if this was such a great set-up, why did Polaris abandon the 755cc engine after just one year? Do you have any dyno statistics (HP & torque) for the 2006 Polaris 700 (755cc). I’ve seen stats on the 900 and it is really peaky, all the HP & torque are on top with very weak bottom end and mid range compared to Cat 900. Does this curve also apply to the 755cc?
We ran dyno graphs of both the 900 and 755 in the Oct/Nov 2005 issue of SnowTech. It pulled 138.5 HP at 7500 rpm with 99 foot-pounds of torque at 7200 rpm. With the SLP pipe and ignition reprogramming (at any Polaris dealer) it was 20 pounds lighter, pulled 146.2 HP at 7600 rpm and over 100 foot-pounds from 7200 to over 7600 rpm.
The overlay of the two is similar, but the 755 is a bit stronger down low and through the midrange. Remember the Cat 900 was very meaty all the way through, and the 755 is more like this than the Polaris 900 was. I wouldn’t call the Polaris 900 “peaky” as you refer to it, but I guess it is peaky when compared to the Cat 900.
Why only one year for the 755? Two things – the small block (Dragon) 700 was an easier project than they anticipated, and the engine was able to be readied for production a year earlier than anticipated. Also, Polaris had developed a new motor mount system for the 755 and 900, but during durability validation testing they failed a bulkhead and they didn’t know if they could nail it down in time for 2007 production. They opted to suspend the big block 755 and 866 (900) for now, they might be back for 2008. Maybe.
The 755 should be a good sled once some of the weight is removed, as we found it a bit heavy, but all and all a good performer. If it is equipped with a SLP single pipe kit, an SLP air box kit, a torque arm and a push arm, it becomes a really good sled. Belt life is improved, it gets very responsive and top end power (and speed) increases. Low rpm operation is deceptive, like the 800 and 900 Cat motors. We ran a 755 for the entire season last winter, not a problem.