If ever there was a risky writing topic to take on, it’s this one. It is from my memory and my opinion only that I have selected these 10 patents/designs that I consider to be the most influential in the development of the snowmobile from its creation to this day. I would love to hear from readers if you feel I have dropped a major step in the most important advances of the snowmobile. I have dismissed legislated requirements (sound levels, emissions, size, lighting, etc.) as design points of reference. Every manufacturer has had to deal with these regulations and they have done an incredible job of complying with them.
No. 1: The First Snowmobile Was Patented
The first significant step forward in snowmobile development was the 1927 creation of the Eliason Snowmobile in Sayner, Wisconsin.
Inventor Carl Eliason’s original machine was powered by a 2.5 hp outboard engine, which was mounted in front of the rider. His concept was to “float” the machine on a toboggan-like bellypan and skis that ran the length of the machine. That design allowed the track system to simply propel the machine, not float it. The track assembly was made from chain with wooden cleats fastened to it for traction. The track was driven by a set of forward-mounted drive sprockets, which engaged with the chain, and a set of rear idlers that allowed the track to rotate around them to return to the front.
The track was guided by a pair of slide rails. Guides fitted to the track followed the rails to keep it running straight. This “slide rail” system was not really a suspension system in that the assembly did not suspend the machine, it only propelled it, following the contour of the snow as it floated freely below the snowmobile itself. The machine looked like a powered toboggan.
For 15 years, Eliason refined and developed new designs of his sled. Later machines used air cooled motorcycle engines with unit-constructed engine/transmission designs. His machines of the 1930s utilized twin cylinder, 12 hp Excelsior engines and later, V-twin, 25 hp Indian engines. Eliason even produced a few units with a Henderson four-cylinder motorcycle engine.
After World War II, the business was sold to Four Wheel Drive Auto Company (FWD) of Clintonville, Wisconsin, and eventually moved to the company’s Ontario office. More models were developed, including the 1950 model K-10 with a Salsbury 6 hp engine and variable ratio, belt driven, drive and driven pulleys. This was the first use of a CVT on a snowmobile and was the basic transmission system that we still use to this day.
No. 2: Ski-Doo And The Endless, All Rubber Track
In Valcourt, Quebec, Joseph-Armand Bombardier developed a rubber-covered drive sprocket design in 1935, which led to his development of many successful track drive systems. Bombardier received his first Canadian patent for this track drive system in 1937.
In 1957, Bombardier’s oldest son, Germain, was designing a ski trail groomer. The design included a seamless, rubber track that floated the machine as well as propelled it. This machine provided the final inspiration for Bombardier to focus on a small, one- or two-person snowmobile.
After developing several single and double tracked machines, Bombardier decided on his final design in 1959. An incredibly talented inventor and fabricator, Bombardier even developed and built the vulcanizing machinery he would need to produce the soon to be patented seamless rubber track. Germain Bombardier received his Canadian patent on the seamless rubber track in 1960 and for the United States in 1962.
Bombardier’s Ski-Doo, first sold in 1960, provided new technology to the fledgling snowmobile industry. The little machine mounted the engine on top of the tunnel. The chassis and hood was a single piece with the fuel tank formed by the belly pan and the tunnel. The total weight of the machine was 335 pounds and the endless rubber track was suspended by sprung bogie wheels.
The Ski-Doo was to become the most copied snowmobile design of all time, though getting around the patented endless rubber track forced many of the soon-to-appear competitors to use built-up cleated tracks.
No. 3: The First Slide Rail Track Suspension System
A major departure from early suspension design appeared on the 1965 Arctic Cat Model 140 Deluxe. Rather than sets of bogie wheels suspending the machine on the track, a pair of slide rails ran on the cleats of the track between the rubber belts of the track to suspend the machine. All other machines at that time were running with bogie wheel suspension systems.
The inventor of the system was a development technician at Arctic Cat, Roger Skime. Today, more than 40 years after he started with Arctic Cat, Roger is vice president of engineering and has been involved with numerous innovations in snowmobile technology and has his name on many patents.
The slide rail suspension system forced the track to remain flat beneath the machine and not follow the contours of the bogie wheels. This made the machine faster and allowed it to “bridge” bumps for a smoother ride. The system also allowed room for the use of shock absorbers and various spring types, many of which could be adjustable. The slide rail suspension system on that 1965 Model 140 alerted the snowmobile industry that things were about to change.
No. 4: Forward-Mounted Engine Chassis Design
Until 1966, there had been only three major designs of snowmobile chassis. The original Eliason motor toboggan with the motor in front of the driver and track, the FWD design with the engine mounted behind the driver and on top of the track drive unit, which early Polaris and Arctic Cat models followed and the Bombardier design with the engine mounted on top of the track tunnel and in front of the operator.
Arctic Cat introduced the next major innovation in snowmobile design with its 1966 Panther — a major leap forward in snowmobile design. The chassis was made of aluminum, it sported an advanced version of the company’s revolutionary slide rail suspension and the engine was moved forward and down into the belly pan, in front of the track tunnel.
The new Arctic Cat was truly impressive. The ride was way beyond any other snowmobile of the time and the handling was simply superb for the day. The forward mounting of the engine placed more weight on the skis and balanced out the machine with the weight of the rider. This new engine position also lowered the center of gravity (cg) of the sled, which was a major factor in improving the sled’s handling.
The 1966 Arctic Cat Panther made the entire snowmobile industry refocus on how a snowmobile should be designed. Eventually, all manufacturers gravitated to the Arctic Cat chassis design. The four major snowmobile manufacturers that remain today incorporate the engine-forward design. It’s tough to beat a great design.
No. 5: The Polaris Clutch
When I started working with snowmobiles in 1968, the only significant improvement in the transmission system since 1950 was the addition of a cam to the driven pulley to control upshift speed and force a faster downshift. We all knew something big had to be done with the clutches to make use of the power we could squeeze out of the engines with increasingly high rpm and narrower and narrower power bands.
At a Duluth, Minnesota, indoor snowmobile race in the fall of 1969, our race team had heard rumors through the summer that Polaris had a new clutch design and this would be my first chance to see it and how it functioned. Leroy Lindblad fired up his also-new little Fuji twin 295 and revved it up. I’ll never forget it. The sled didn’t move and he was running the engine at over 4000 rpm. I knew our race team was in big trouble. We learned that the new Polaris clutch could be adjusted to allow any engagement speed and the upshift could be custom tuned to follow almost any power curve produced by an engine.
The Polaris innovation did far more than just change how the CVT shifted — it changed how snowmobile engines could be designed. Before the Polaris clutch, engines had to produce a lot of torque at low rpm to deal with the immediate engagement of the clutch and its linear upshift based on rpm. The new design allowed a peaky, high horsepower engine to be used. This meant that low speed torque was no longer a needed commodity.
The new clutch design from Polaris made a new, single cylinder, rotary valve racing engine from Rotax obsolete. The critical need for huge low end torque ended with the development of the Polaris clutch.
All of the high-performance drive pulleys in use today employ concepts that were developed by Polaris that were first used in its drive pulley on the TX models for the 1970 model year.
There have been many advancements in the clutch designs since Polaris first introduced that major step forward in 1970, but the basic concepts of that early design remain almost exactly as the original prototype.
No. 6: The Carbide Runner Appears
I raced on the Halvorson Race Team during the winter of 1970-71. Because snowmobile racers have always searched for more traction, we tried welding beads of stellite rods with sharpened edges to our wearbars. The stellite was hard and stood up better than a plain mild steel bar. During that season, another Halvorson race team, the Rudbec Brothers of Brainerd, Minnesota, worked up a wear bar that worked well but wore quickly.
The Rudbecs had used a 1/2-inch wear bar and milled a 1/4-inch by 1/4-inch “V” groove down the middle of it. Most wear bars were 3/8-inch in diameter at that time. This new design provided two biting edges on the bar. We tested them and they worked well but their mild steel composition didn’t hold up. We ended up brazing square files into the “V” groove and the well supported file stayed put.
We supplied a set of these modified, Rudbec bars to the Bombardier factory who took them one step further. The square files were tossed aside, and the race department instead brazed pieces of carbide into them. Bombardier first used carbide runners on its 1972 Blizzard race sleds. The carbide runner was invented and Bombardier patented them. They are virtually the only runner still in use on all snowmobiles.
No. 7: The First Liquid-Cooled Snowmobile Engine
Liquid cooling showed up first on race sleds. The first sled I recall actually using liquid cooling was a single-cylinder Thunder Jet built by Jim Adema. Adema had milled the fins from the cylinder and head, welded on water jackets and fitted a small radiator to the front of the sled. A washing machine water pump was belt driven from the jackshaft to circulate the coolant. This was circa 1971.
The manufacturers and their engine suppliers were all looking at liquid cooling in the late 1960s and early 1970s. It was one way to significantly lower the sound levels to legal levels while maintaining great performance.
The first actual liquid-cooled, production snowmobile was the 1972 Brut LC44.
Brutanza Engineering Inc., of Brooten, Minnesota, was established in 1971 by Gerry Reese, Mike Baker and Marley Duclo who were engineers and racers from Polaris. Brutanza put together an amazing machine that was ahead of its time and incorporated a lot of truly innovative engineering. Like the others, the first Brut was radiator-cooled.
The boys at Brut quickly discovered that when the machine had to idle for extended periods, such as on starting lines at race events, the engine could overheat. Midway through the first season, Bruts showed up at races with finned copper tubes on the insides of the track tunnel through which the engine coolant was circulated. This evolved into aluminum extrusions that were mounted inside the tunnel. Brut patented the heat exchanger concept and the industry still uses it today in many variations.
No. 8: Independent Front Suspension
IFS, as we look at it today, incorporated automotive designs that first seemed to take hold with Chaparral’s 1972 IFS factory race sled. The machine got a lot of attention but never enjoyed much success on the track. An independent racer, Gordon Rudolph, picked up on Chaparral’s concept and developed his own version for use on a Polaris. Rudolph experimented with the design for several years and learned a lot about what was needed to make the system work.
With the advent of the SnoPro racing circuit for the winter of 1973-74, Gilles Villeneuve, working with Alouette, developed the famous twin-track racer that sported an IFS front suspension system. The heavy sled was slow off the line but its superb handling and high cornering speeds caught people’s attention. The twin-track Alouette broke down a lot and kept the mechanics scrambling. Villeneuve won one SnoPro event with the sled in Peterborough, Ontario.
Alouette dropped out of snowmobile racing but Villeneuve and his brother Jacques showed up in mid-January of 1976 with a fleet of totally new, IFS Skiroule race sleds of mostly Gilles’ design. Though the brothers got a bit of a late start in the season, Gilles went on to show all the factory racers that if they didn’t have an IFS sled for the next season, they might as well stay home. Gilles was racing on what many called the roughest track of the season on January 24-25, 1976, in Lancaster, New Hampshire. He ended up winning every Super-Mod event each day.
Polaris knew right away who to go to as it started development of IFS sleds: Rudolph. With Rudolph’s help, the Polaris race team put together an IFS sled that became the new point of reference for the industry. Polaris dominated with its factory IFS race sleds and began producing a production racer known as the RX-L. Polaris released its Joe Average consumer available IFS sled with the 1980 TX-L Indy.
No. 9: Coupled, Long Travel Rear Suspension
While racing certainly provided the impetus to develop IFS, there was never a big push to improve track suspension designs for the consumer until Gerard Karpik surprised the industry with the success of his M-10 suspension.
Known as “King Karpik” in the days of his domination of cross-country racing, he put on enough miles to know he wanted a lot more from the suspension systems than were delivered in the late 1980s.
Increasing the vertical travel of the suspension allows it to soak up bigger bumps, but it can also raise the machine’s cg. Random movement of long suspension arms can create many strange reactions on machines, too. As Karpik and the rest of TeamFAST studied long movement designs, it was noted that when the front of the track contacted a bump, the rear of the track and suspension was hanging down ready to hit the same bump again. A “coupling system” was needed to allow the front and rear arms to communicate with each other.
Karpik designed and patented the coupling system which was the key to making a long travel suspension work well. He started selling his new M-10 suspension by the hundreds and word of its incredible performance spread quickly. The manufacturers’ focus groups started getting more and more requests for improved suspension designs on their own sleds based on the reported performance of the FAST design.
Manufacturers discovered that without a coupling system, new designs weren’t performing as they had hoped. As patent rights were spread around, the industry benefited from far better riding and handling snowmobiles. There is no question that the FAST M-10 design drove the industry’s development of long travel track suspension systems.
No. 10: Chassis With Lower CG, Mass Centralization And Rider-Forward Design
Ski-Doo shocked the snowmobile industry when it unveiled its radically new REV design as a Pro Open snocross sled in 2001. The new design placed the rider one foot forward of the “normal” riding position, centralized mass on the chassis and utilized a pyramidal frame that spread suspension forces over and around the engine to the entire chassis without adding weight. They weren’t, however, the first to do it. FAST did.
The success of FAST’s M-10 suspension put the heat on all snowmobile manufacturers to improve the ride and handling of their machines in the 1990s. Increases in suspension travel required higher cg and early long travel sleds suffered in the handling department. Part of the handling problem could be blamed on the higher cg of the components, but part could also be blamed on chassis flex. FAST recognized these problems and set about designing a complete machine.
Gerard Karpik and his team at FAST knew they had to lower the cg, maintain or increase suspension travel, keep the weight down, shift major weight sources like the engine lower and rearward in the chassis and stiffen the chassis.
FAST threw out its conventional tunnel and bulkhead or cross member design for what it called their Delta Perimeter Frame (DPF). The DPF is constructed of multi-cell aluminum extrusions that are welded into a triangulated configuration that wraps over and under the engine, allowing suspension loads to be spread evenly around the chassis. The track tunnel is simply a cover over the track and is not used as a structural part of the frame.
The first Blade snowmobiles from FAST were sold as 1998 models and were enormously expensive compared to other production machines of the time. The Blade, and later the REV chassis, changed snowmobile design forever.