1997 yamaha 700 sx

 Will the real Yamaha Vmax 700 SX c'mon down! The prototype we rode in northern Wisconsin this past winter was superb. It met all of our criteria for handling, ride and performance. We found the 700 SX to be the performance machine that Yamaha told us it would be.

Keep in mind that when we tested that first 700 SX, almost a year ago, it had a crew of top-level Yamaha technicians attending its every hiccup. And we didn't have any sleds - other than last year's Yamahas - to compare the prototypes gainst. We were impressed.

Last March, when we test rode the Vmax 700 SX and the other new for '97 Yamahas in Stanley, Idaho, we weren't so impressed. There were more sleds to compare against the Yamaha Vmax prototypes, and there were many more magazine test riders and many fewer Yamaha technicians with much less time to spend baby-sitting the new sleds.

In addition to test riding the new models and letting our test crew evaluate them, we also scheduled an hour of speed runs on the air strip. The Yamahas were scheduled first. Since we didn't know how Yamaha would fare against the other brands on the wet and heavy snows we encountered at Stanley, we decided to wait until getting back to the office to analyze our data. When we did, the 700 SX looked slow, even versus the Vmax 600 SX, Yamaha's smaller displacement win-cylinder sports package.

Now how could that could be? Both sleds are lightweight. The new 600 twin is putting out 103-ish horsepower and the 700 triple is said to be in the 110-115 power range according to dyno tests we've seen. That's enough power to outrun the 600. But we also found that the Stanley edition of the 700 SX wouldn't outrun the 700 Mountain Max. But then, over the summer, we kept seeing the 700 SX running among the winners in grass drags. So, what was wrong?

The reason our test sled in Idaho didn't run as well as what you will get from your dealer is that Yamaha had fit our test unit with an experimental YSX clutch, the one that was hyped in the early promotional materials you would have gotten from your dealer last spring.

Faced with a shortage of time and parts to make the new primary drive work, Yamaha eventually opted for its older-style clutch for use on the new 700 SX triple. What you'll get from your dealer is the properly clutched 700 SX that will run rings around our test sled and should challenge last year's big news story, the Ski-Doo MXZ 670, for trail performance bragging rights. That's exactly what Yamaha wants.

But if you are thinking that a sled with a three-cylinder 700cc engine should automatically challenge the Mach 1 or Ultra SPX three-piped triples, get over it. Those straight-line rockets have up-wards of 15 horsepower or more than the single-piped Yamaha triple. A set of aftermarket pipes, a port job and clutch kits from PSI, Hauck's, Bender's, Maxximum and others will level the playing field against those braw-nier sleds. In initial private dyno sessions, it has become obvious that Yamaha is opting for mild, not wild with this new triple. The ports are reported to be small and very conservative.

A set of pipes without porting will add 15 horsepower or so, bringing the sled into the 130-horsepower range. With more radical engine work, there's the potential for at least 150 horsepower.

Don't look for any official Genuine Yamaha Technology (GYT) triple pipe
kit for the 700 SX or a special pipe for the new 600 twin this season. Yamaha
tells us there won't be any such kits before the season is over.

Do look for the all-new 698cc liquid-cooled triple to sit compactly in
the engine bay. Yamaha delivers this lightweight three-banger with case
reed induction, triple exhaust ports and three TM33 Mikuni carburetors.
Look behind the windshield and you'll find the cold air intake for the flat
slide Mikuni carbs. It guarantees a fresh supply of air.

With terrific torque spewing from an all-new triple, Yamaha's decision
to go with a three-into-one pipe setup was very deliberate. Yamaha wants
this sled to combine beefy low end and midrange power with a competent,
high-revving top end. We found a quick throttle response thanks to its digital
electronic system, which makes this sled fire precisely.

Power was to be controlled by a new YSX overdrive clutch. We expect this
clutch will appear next season. The prototype YSX clutch had 14-degree sheave
angles and wide pin supports for rollers and weights. It's open face design
helps keep cooling air flowing.

What you'll actually get is pretty much business as usual with the venerable
Yamaha primary and driven clutches. Look for 700 SX-specific weights and
springs that will give the sled very capable performance, (better than what
we saw in Stanley.)

In fairness to Yamaha, had we known that the triple's clutch was off
its game, our riders might have marked the 700 SX higher. Despite its substandard
clutching, though the 700 SX left a positive impression with those test
riders who only had the Stanley experience on which to base their opinions.
The riders gave the three-cylinder SX "8s" in comparison to 8.6
for the twin-cylinder MXZ 670.

While performance will be a factor, Yamaha expects handling and light
weight to be two very impressive factors for 700 SX buyers. Yamaha wants
to define the meaning of power to weight with the new SX models. They are
aimed at being as light as Ski-Doo's 1996 MXZ 440 cross-country racer while
providing quite a bit more usable trail power.

The Vmax 700 SX is a cruise missile aimed at Ski-Doo's MXZ 670. According
to our test riders, though, Yamaha's new missile isn't fully locked on for
1997. Overall, our test guys rated the Yamaha well at 7.12 points out of
a possible 10, but the MXZ 670 was the second-highest rated sled of our
test session at 8.36 points.

The ProAction Plus SX rear suspension is a trail charmer delivering 8
inches of travel. Our riders rated it above average at 7.4 points for ride
and 7.0 points for handling. A redesign of the front torque arm in the SX
rear suspension provides longer actual suspension when it encounters a mogul.
This W-shaped arm lets the rear shock pass through the front travel area,
maximizing the rear arm's travel. Made of lightweight aluminum, the Kayaba
shocks are rebuildable and nitrogen-charged for severe service.

Up front we were more critical, rating the SX ride at 7.0 and the handling
a 6.8, both still quite above average. The three-cylinder Vmax 700 SX relies
on Kayaba shocks that are mounted to give less total travel (7 inches versus
9) than you'll find on XT and XTC models. All models feature a link-type
stabilizer bar to control side-to-side ski loads. Both the 700 and 600 SX
versions feature a race legal 41-inch, center-to-center stance.

The similarly outfitted Vmax 600 SX uses the Öhlins shocks while
the 700 SX comes standard with gas cell shocks. Yamaha had to make a choice
between the two models. While both carry the SX designation, which is code
for Yamaha's sports handling package, Yam-aha was aware that Öhlins
wouldn't be able to deliver enough shocks for both models. The 600 SX won
out and is designed to be Yamaha's premier handling sled. The 700 SX is
the performance handling sled.

This lightweight package draws benefits from the unique subassembly system,
which provides attachment points for the engine, front suspension, steering
componentry, and serves a key role in of the new sled's torsional rigidity.
Unlike more conventional designs, the Yamaha bulkhead reduces complexity
in manufacturing, shaves weight by reducing the number of pieces required
to do the same functions - new Vmax has as many as 300 fewer parts than
just the 1996 version - all the while increasing strength.

Yamaha worked hard to reduce weight while adding structural rigidity.
But depending on the engineer you talk with, this can be a good or bad thing.
One school of thought suggests that structural rigidity should be stiff
because it enhances handling. Another view is that a snowmobile needs certain
inherent flexibility that lets the chassis twist as it handles uneven terrain.
Features we liked on the 700 SX included the racing-inspired hydraulic disc
brake with its dog leg shaped lever. The new Nissin-built brake is an all
star and very smooth to operate.

Ergonomically, the SX feels good. The handlebar is raised and straighter
for a sportier feel. The seat's rear bun is raised, and when combined with
canted footrests, you can really lock yourself into this sled. With your
lower body securely in position, you can keep a lighter touch on the handlebars
and let the sled work for you. Try it for fit on the dealer showroom and
you will understand what we mean. Like the Ski-Doo MXZ, the Yamaha SX models
have a rider friendliness to them, which extends to the light pull of the rack-mounted, flat slide Mikuni carbs.

But as a cruise missile aimed at the MXZ 670, the 1997 Vmax 700 SX needs
a little better aiming device. But consider this Yamaha's warning shot that serves notice to Ski-Doo and the rest of the industry that Yamaha can still build extremely good snowmobiles that will be much in demand.