Check out this little tidbit about the new breed of high tech synthetic and organic base 2 stroke oils being made in an effort to clean up the emissions of snowmobiles, outboards, jet skis, dirtbikes, ATVs, ect. I have personally witnessed the difference made by synthetic oil in a 2 stroke engine as far as exhaust is concerned. Ride behind somebody on a "weed eater" some time and you'll know right away if he's running synthetic or not. If you're gasping for air and your eyes are watering profusely, he's running mineral based oil. Synthetic gives off a slight hint of that tell tale "2 stroke aroma", but not nearly enough to be obnoxious. You practically have to go up and sniff the tailpipe to smell it unless there's absolutely no wind.
Now most ATVs, a lot of dirt bikes, several outboards, some personal watercraft, and a handful of snowmobiles are being made with 4 stroke engines, which is mostly a good thing. Not only are 4 strokes more environmentally friendly, they're a lot more reliable (debatable, just my opinion), last longer (also debatable), are affected far less by variables such as temperature and altitude, and they run cheaper since they burn less fuel. But 2 strokes still have some distinct advantages that just haven't been duplicated in a 4 stroke platform as of yet, and likely won't be due to the inherent differences in the theory behind how engines operate. Modern technology has tackled some seemingly insurmountable obstacles regarding internal combustion engines and 2 stroke engines are no exception. Some surprisingly clean burning 2 strokes are available now, with more on the horizon, but more on that later.
4 stroke snowmobiles, primarily, just haven't taken off quite the way many people, including the manufacturers, had originally hoped that they would. The reasons are complex and many, but mostly revolve around the little green monster called power to weight ratio. 4 strokes as a general rule just don't make the amount of power per pound that 2 strokes do, and the power that they do make is produced in a different way. The rpm specific narrow power band of a 2 stroke is just seemingly tailor made for the way that snowmobiles operate. Add that to the fact that 4 strokes take a little longer to "spool up" than 2 strokes do since they have more reciprocating mass, and there's just no replacement for that instant snap of 2 stroke torque.
Snowmobile CVT clutches are designed to keep the engine at a nearly constant speed while varying the gear ratio in order to vary the speed of the sled based on power output related to load, a situation that is just simply better suited to a 2 stroke. Couple that to the fact that most of the little 2 stroke "inconveniences" that all of us have been dealing with for years have been virtually eliminated on the newer sleds, and it's no wonder that the few high performance market targeted 4 stroke machines available just haven't been big hits with consumers. The overly portly 4 strokes are just not very appealing to anyone but the geriatric trail touring crowd that are still hoping that Yellowstone Park will get opened back up. Don't hold your breath folks, the tree huggers won that one.
Now 20 years ago, just about any sledder would have most likely jumped at the chance to ride a 4 stroke sled that was as close to traditional power to weight ratios as the 4 strokes that are being made today. The only trouble with that little scenario is that 2 stroke technology has advanced in the last 20 years as well. The old air cooled, carbureted sleds were extremely finicky when it came to air fuel mixture, a requirement that changes drastically with changes in altitude and temperature commonly encountered on a typical ride. The modern sleds address this problem quite well. Liquid cooling made the engines a little less sensitive, but 2 strokes are notoriously finicky about jetting. With the advent of various automatic altitude compensation devices, up to and including electronic fuel injection similar to that found on cars, the days of constantly reading spark plugs and fiddling with carburetors in a quest for the optimum jetting only to have the temperature change and make you start all over are gone, but an interesting little side effect of these systems is reduced emissions. You will never hear anyone complaining about a sled that smokes less as long as it's getting proper lubrication and isn't in the process of reducing itself to scrap aluminum.
Reduced emissions were the primary reason for the move to more 4 stroke machines in the first place, that and longevity and fuel economy, and reliability, but in spite of the explosion of 4 strokes in every other form of power sports, 4 stroke snowmobiles just haven't caught on, and for good reason. Not only are the 4 stroke sleds heavier, which poses a big problem on a snowmobile, they just simply lack the performance necessary to keep people interested, and they're more expensive. In spite of the numerous efforts by snowmobile manufactures to produce a viable 4 stroke sled and therefore placate at least a few of the "greens", ultra high tech 4 stroke engines just haven't seemed to solve the problem.
At least one manufacturer has the foresight to deal with this issue. Ski Doo is currently making a 2 stroke sled that takes advantage of some really interesting technology also being used on automobiles to boost performance and reduce emissions. Traditionally, the air/fuel/oil mixture on a 2 stroke engine enters the cylinders through the crankcase via ports in the cylinder walls which are opened when the piston reaches the bottom of it's stroke. While this provides the necessary air movement to get the charge into the combustion chamber, it's just not very efficient, not from an emissions standpoint anyway. The fuel has to move too far and sit idle for too long and therefore begins to deatomize out of the air and recondense. This is necessary in order for the oil in the mixture to do it's job but this liquid fuel and oil often ends up being "blown out the stack" if you will, and accounts for much of the residue that is such a harmful part of 2 stroke exhaust.
With the new system being marketed by Ski Doo, the fuel is injected via typical automotive type fuel injectors directly into the cylinders at the precise moment that it will be best atomized. The result is more complete combustion that when coupled with modern synthetic or organic based lubricants will undoubtedly produce emissions far closer to that of a 4 stroke, possibly even the same, since these machines burn markedly less fuel overall. Less fuel means less smoke, less smoke means cleaner air, who wouldn't want that?
Now many environmental groups would like to convince everyone that people involved in power sports of any type are enemies of the earth, with no consideration for the environment whatsoever, this is simply contrary to the evidence that is all around us. The fact that Ski Doo and other manufacturers would spend the R&D money necessary to come up with a machine like this is just proof that given the opportunity, power sports enthusiasts will pay for the technology necessary to protect the environment. Snowmobile manufacturers are obviously convinced anyway, or else they wouldn't be spending all of this money on research to come up with cleaner machines. It's just too bad that there had to be so much negative publicity first in order to spur them to do it. Sometimes change is difficult, but that doesn't mean that the changes that come about are always bad. In this case both the environment and outdoor power sports in general benefited tremendously.
Products like the oil I linked you to earlier are also proof, the fact that these products sell and sell well is more evidence yet. People will pay more for environmentally friendly products as long as they're readily available and don't have too many undesirable side effects. Synthetic and organic base oils burn far cleaner in 2 strokes than traditional mineral oils, all the while providing better engine protection and longevity. It's a win win situation for everyone, not the least of which is the environment.
These oils are also typically far more expensive than mineral based oils. Expensive to the point that it's difficult to entirely justify them based on the nominal gains in engine longevity that they can provide, to me this is further proof that power sports enthusiasts are willing to spend extra bucks in order to preserve the legitimacy of their sport, and to protect the environment as well. No one wants to ride in a decimated wasteland.
We go riding in remote areas not only to enjoy the thrill of getting there, but to enjoy the peace and solitude provided by these areas once we are there. Environmental destruction is far from the agenda of this rider, and I think it's a long ways away from those of my fellow enthusiasts as well. Now if environmental groups would get off of their high horse and notice efforts like this, maybe we could all work together towards truly saving the environment, from it's real enemies, like profiteering corporations. What good is a healthy forest if no one can get out and enjoy it, or use the resources it provides? I like wildlife just as much as anyone but if deer can live in town like they do around here I really don't see what harm is going to be done to them by an occasional passing ATV or snowmobile. Let's apply some common sense and come up with solutions that are fair and beneficial to everyone, that way we all win, and maybe the deer will go back home to the forest and quit eating your garden. They don't eat my garden, gee I wonder why. ;)