For 2017 Ski-Doo brought us their latest platform, the new GEN 4 REV. This all-new platform of course features the all-new 850 E-TEC engine, designed specifically for this narrower chassis with a focus on mass centralization and agility. So where do they go from here? Ski-Doo said it – “What Matters is What’s Next.”
The 2018 Ski-Doo Line up has been released – Click here to read the SnowTech review of the 2018 Ski-Doo line up!
The beauty of the previous, and still current, REV XS and XM platforms was how both the 2-stroke and 4-stroke engine families all fit into the design. Now, with the Gen 4 REV, it appears only new engines will fit into the smaller, mass-centralized chassis. Yes, it is the next generation, but this obviously leads us to the conclusion that we will not see any of the current engines in the REV-XS/XM going into the Gen 4 platform.
So, what’s next? One has to believe that Ski-Doo already has a replacement for their fabulous 600 E-TEC engine, another 2-stroke E-TEC designed from the ground up to be an E-TEC. Remember, when Ski-Doo came out with the 600 E-TEC for 2009 it was an adaptation of the direct injection technology to their existing 600 SDI (semi-direct injection) engine. The 800 E-TEC was an adaptation of direct injection to their 800R PowerTEK engine. Yes, there was a short-lived 800 SDI, but that engine suffered from long term durability and reliability due to the reduced fuel flow and resulting crankcase temperatures. An engine design might survive on carbs or throttle body fuel injection, but once the fuel flow is cut so drastically, like in the case of SDI or DI, the engine design and cooling system must be changed to compensate for the reduction in cooling from all of the extra fuel. Yep, old-style engines were cooled in part by all of the extra fuel being thrown at them. Reduce the fuel flow, you reduce the cooling. This has been part of the learning curve all along with direct injected 2-strokes, how to best deal with the cooling issues of the pistons, crankshaft, crankcase, all of it.
The 600 E-TEC, producing much less power than the 800R E-TEC, had less of an issue with adequate cooling than the 800R ever did. Even so, we all know that the lessons learned from the many years of production have now cultivated a next-generation of engine technologies, evidenced by the new 850 E-TEC. Plasma-coated cylinders, new piston and ring design, new crankshaft and crank bearing designs, new oiling systems, even an additional set of booster injectors to feed the power, and free up the direct injectors to be more accurate at lower flow rates.
So if Ski-Doo upped the displacement of their 800-class engine to 850cc, it only makes sense that they could or would attempt the same with their next-generation 600-class engine. We would not be surprised one bit to see an all-new 650 E-TEC engine, but will it be for 2018, or will they wait a year for 2019? Is it even ready for production? Making it a 650 shouldn’t cost them any more than it would to make it a 600, and the trend seems to be to provide more for the money. This trend seems to be hot in the motorcycle market, so we tend to believe the 600 E-TEC replacement will be slightly larger in size, just like what happened with the 850. We would expect to see much of the same technology in the 650 as the 850; plasma-coated cylinders, new-style pistons, new crank and bearings, just don’t know if this size would also need the booster injectors or not.
So, maybe the Gen 4 as we have it now will only be used for the new Rotax 2-stroke engines? We do not know for a fact that the 4-stroke engines, the ACE 600 & 900 and the 1200, will or will not fit into the Gen 4, but we tend to believe they will not. Being able to use one chassis or platform across the entire line of engine offerings reduces costs, but creates compromises. Polaris, who only offers 2-stroke engines and has no 4-strokes in their line-up, doesn’t have to worry about such compromises, as evidenced by their sleek and narrow AXYS models. Arctic Cat, on the other hand, wanting to have both 2-stroke and 4-stroke engines in their model offerings, has been fitting both engine types into their ProCross and ProClimb platforms. We tend to believe the Rotax 4-stroke engines will remain in the REV XS platform for now as a stable trail platform, since the Gen 4 models appear to have been developed more for the agility of mountain riding and less for the stability of trail riding. Just an observation. The days of having one platform doing it all might be over with at Ski-Doo.
Originally published in the January/February 2017 issue of SnowTech (December 2016)