Myth or reality!
According to the dictionary, the word “ myth ” means, among other things, “ tale with supernatural beings, collective fantasies ”.
In terms of snowmobile, we are not talking about a monster with two heads, the Sasquatch or else, the Boogeyman, but rather about the Olympique, Everest, TNT, Blizzard, RV or Formula. So many models have left their marks during our era that it is hard to know where to begin. After all, Bombardier manufactures mass-production snowmobiles since fall 1959!
Since we must start somewhere, I am going to introduce you to models that I know pretty well and that are my favorites.
A myth is not necessarily created instantly from one day to the next. In this case, it has been with extraordinary innovations and continuous improvements that Ski-Doo will bring to life another snowmobile that will make history. The name! Ski-Doo Mach 1 and Mach Z.
In 1989, Bombardier wanted to raise the bar even higher with the introduction of the Mach 1 583, built from the PRS chassis (Progressive Reaction Suspension) present since 1985 and on which many technical updates had been achieved during the last years. Among these innovations, we must notice with the arrival of the Mach 1, a new track of 121 in. / 307,3 cm long instead of the traditional 114 in. / 289,6 cm, a seat that covers the tank and a storage space in the rear part of this seat. The main innovation of the lineup is of course the famous 583 R.A.V.E. engine with rotary valve. This engine has been produced until 1999 and has been used on many machines.
1985 Formula Plus with track of 114 in. / 289,6 cm (Photo courtesy Maxmachz)
1990 Formula Mach 1 with track of 121 in. / 307,3 cm
In 1988, Ski-Doo relied on the Formula Plus 521 to compete with the Wildcat 650, Indy 650 and Exciter 570 that all had the advantage of engine size. So, it was about time for Ski-Doo to bring some modifications in order to remain competitive. Without drastically increasing the displacement, Rotax worked mainly on the addition of new technologies to produce a compact and powerful engine. Already, with its 521 engine with rotary valve and 40 mm carburetors, Bombardier had nothing to envy of other manufacturers in matter of power per CC ratio. Now, Ski-Doo goes to war with its new 583 R.A.V.E. (Rotax Automatic Variable Exhaust) with rotary valve.
1986 Formula Plus engine (Photo courtesy Maxmachz)
1989 Formula Mach 1 engine (Photo courtesy SkiDoojunky)
Unsatisfied with the performances of its 1989 newborn, Bombardier proceeded to a list of modifications in the middle of the season to increase the overall performances of the Mach 1. Here is a summary of these modifications :
- Re-tuned carburetor with new needle jets and new position of the needles.
- New rotary valve.
- Addition of 2 openings of 1.75 in. / 4,45 cm at rear of the air box.
- Modification at the exit of the tuned pipe.
- New calibration of the driven clutch.
- Addition of a new set of wheels and new spring on the rear suspension.
- Machined engine head.
In 1990, Bombardier comes back mostly with the modifications achieved in the middle of the 1989 season and with new graphics.
1989 Formula Mach 1 (Photo courtesy SkiDoojunky)
1990 Formula Mach 1
Once again, Ski-Doo innovates with a new engine for the next two years. For 1991 and 1992, the engine goes from the 583 (bore 76 mm x stroke 64 mm) to 617 (bore 76 mm x stroke 68 mm), carburetors come back to 40 mm instead of 38 mm on the 583. Also, the hood is totally new and more aerodynamic. For 1992, Bombardier offers a new more comfortable seat, new C7 rear suspension and ski stance goes from 36 to 40 in. / 91,4 to 101,6 cm for increased stability.
The last major modification brought to the PRS chassis has been done to the engine once again. From the 617, Rotax increased again the displacement to 670. Even from 1993 to 1994, Rotax will bring many improvements to it. Personally, I think that this engine is one of the reasons why this model is among the Ski-Doo mythical snowmobiles.
1993 Formula Mach 1 670 and 1993 Formula Plus X 583 (Photo courtesy Jean-Francois Leclerc)
1990 Mach 1 583 engine
1991 Mach 1 617 engine
1992 Formula Mach 1x 670 engine (The standard Mach 1 was the 617 with 1 tuned pipe in 1992 such as the model of 1991) (Photo courtesy JVP)
1993 Mach 1 670 engine (Photo courtesy Jean-Francois Leclerc)
1994 Mach 1 670 engine
In a series of articles about mythical and antique snowmobiles, SledMagazine.com will show you how to bring back to life one of these beasts. In many articles, we will see how to disassemble, to clean, to paint the chassis components. Updating the engine. How to remove the old dried stickers and to place new ones. And finally, how to bring back the old drive and driven clutches to their initial conditions.
The chosen model…! A 1994 Mach 1 with broken engine, electric start and reverse. Lot of work ahead…
1994 Formula Mach 1 670
1994 Mach 1 670
