1989 mach i

Call it Ski-Doo's Formula Fast. Call it a continuing step in the evolutionary development of "Ski-Dooing" which we first encountered in the mid-'60s.

Ski-Doo's new Mach One is the best production Ski-Doo to date. It has a supple and plush new suspension. It has a full coverage - from handlebar post to rear bumper - cushioned seat. It has an evolutionary rotary valved, liquid-cooled twin cylinder engine with snowmobiling's first production variable exhaust port system. It has a unique two-stage thumb throttle which is impressively simple and, yet, extremely clever and efficient.

Yep, we like the new Mach One.

What we like best is the ride and performance combination. Take away the unique Rotax Automatic Variable Exhaust (RAVE) and we still like the Mach One. Leave it in and you Bomber pilots who have been waiting patiently for the Quebec company to unveil its top line performer will be delighted. Is it the measure of the Wildcat and Indy650? We don't honestly know. Yet!

Our best guess is that the Mach One is in the ballpark. In Valcourt last year we overheard technicians telling foreign distributors that the Rotax rocket was faster than one, but not as fast as the other on ice. In snow the situation reversed. Just bet that in some corner of the snowbelt, there will be a couple of Mach Ones that can tear an Indy and a Wildcat a new exhaust port or two!

The new Formula Mach One comes with a bigger rotary-valved Rotax engine than last year's top gun Plus. It also has a few more tricks up its exhaust system, namely the RAVE system. Adjustable exhaust valving isn't new, of course, Yamaha has enjoyed success with its Yamaha Power Valve System equipped two-strokes for years. The concept is new to consumer snowmobiles, although Ski-Doo has brought out an occasional RAVE-equipped racing engine in the past.

The RAVE system is very noticeable. You'll see a bell-like housing near the exhaust ports. It's a clue to the system's inner workings. Simply, there is a guillotine slide sitting in the exhaust port. Under normal conditions it hangs down, effectively reducing the size of the exhaust port and letting the engine provide a wide band of power at low and mid-range speeds. It is said that the engine delivers up to 50 percent more power at the low end - we gather that to mean 50 percent more than a non-RAVE engine.

As engine revs increase and exhaust pressures build, a passage diverts some of the pressure to a diaphragm in the bell-shaped housing. The slide is forced upward, increasing the port size and effectively allowing the rotary-valved engine to churn out a strong top end. Translated as top speed.

The system allows engine tuners to lessen the compromises they would have to make otherwise between low end, mid-range and top end performance levels. The Mach One's 580cc liquid-cooled twin can offer performance in the same range as the Wildcat 650 and Indy 650. It'll be quick from turn to turn with very good top end for lake running.

The Total Range Adjustable Clutch melds extremely well with this engine. You can make the clutching adjustments on this design yourself by dialing in the multi-position clutch adjusters. You can also dial in the RAVE's power characteristics by adjusting the spring valve tension on the valve.

This sled may be one of the most consumer adjustable snowmobiles ever manufactured, especially when you add in the adjustments you can make on the new suspension.

Exclusive to the Mach One is a new Ski-Doo suspension system that absorbs more moguls and is smoother overall - than any Bomber unit to date. The new Progressive Reaction Rear Suspension has a single coil over shock that controls the rear suspension arm. It is laid parallel with the top of the track as opposed to the more conventional up-and-down or tilted positions used in the competitions' high performance sleds. Just as with the front laid back suspension shocks, this rear shock can deliver greater action and increases usable shock travel. The rear shock is multi-adjustable for ride control settings. Reports on the new suspension have been very good. Having test ridden the unit, we have to agree. The ride is vastly improved. Expect - and hope - to see this suspension on other Formula machines in the years to come.

The performance Ski-Dooes also get a two-stage throttle. Don't raise your eyebrows, this is a really functional set-up. You probably had no idea how much half-throttle riding you actually do. You'll find out after a few miles with this easy-pull throttle system. The first state of throttle play is light and takes you to about half throttle when the second stage takes over. The pressure on the throttle starts to get heavier and heavier up to wide open. The idea is to give you ease of operation and a relaxed throttle thumb at low to moderate trail speeds, but to let you know by a heavier feel when you start to enter the danger zone where you should be paying plenty of attention to what you're doing!

We have to admit, that before we tried the set-up we were skeptical about even needing it. It sounded like a waste of an engineer's time and effort. We were wrong. Once we spent some time with the two-stage throttle, we found ourselves really liking it. Frankly, we were very surprised at how much time we spent riding at half or less throttle. It's more than you think.

We like the new Ski-Doo. We prefer the formula red of the Plus, but can live with the black styling of the Mach One. We truly enjoy the full covered seat. A complaint we had with the early Formula sleds was knee-bashing on the fuel tank. That is not a problem now. We like the sitting position. You feel in command - which is good considering this sled's potential.

Even if you're not into speed and all-out performance, the Mach One is worthy of consideration. It is very much like the Wildcat, in that it is a very comfortable trail sled, docile when you want to take it easy and aggressively quick when you don't. Like any top-of-the-line snowmobile, the Mach One is loaded with goodies. It has a huge 10.8 gallon fuel tank - biggest standard tank in the biz! A halogen headlight gives you a clear picture of the trail ahead for night running. And there are the standard assortment of gauges. You can opt for heated handlebars, a hitch kit, and a high windshield.

We'd take the Mach One in any form. It's a smooth riding sled with great performance and a tradition that stretches back nearly 30 years. We like it. And we think a lot of you current non-Bomber pilots will, too!