Yamaha Works 250 Monoshock
Yamaha Works 250 Monoshock
World’s First Impression:
Bob Atkinson
“KARSMAKERS’ YAMAHA? Yeah, I've seen it. That thing really flies. Man, it just goes over the whoops and potholes like they aren’t even there. Incredible!”
“Did ya see that? Karsmakers hit that ledge on the downhill flat-out in fifth and stayed with it. Nobody does that unless he’s riding something trick.”
“Right on. If I had a bike like that, I could blow the world into the weeds.”
Well, that’s just exactly what you feel like when you swing a leg over a Monoshock Yamaha; you feel like you can blow the whole world into the weeds. I know. I rode one. Here’s what it’s like.
The bike is kind of high; like a production YZ. In fact, the feel when the machine is at rest is so similar that I couldn’t resist glancing at the rear end to see if a pair of Thermal-Flow shocks weren’t bolted in place.
There was nothing visible (the suspension components are located under the gas tank), so I swung the kick starter lever out and gave it a couple of quick prods. The 250cc Single sprang to life with a loud crackle. There isn’t much flywheel, so throttle response with the machine in neutral is instantaneous.
The bike is a bit tricky to maneuver through the pits, because the clutch grabs rather suddenly, making it easy to stall the engine. But this is one case where nobody really cares. Racing starts are no problem. Just grab a handful and go.
I spent the first couple of laps familiarizing myself with the machine, and at my relaxed pace, the Monoshock delivered a rough ride. It didn’t hop around or anything like that, but I could definitely feel every bump on the track.
At first I was disappointed. Then I > thought about it and realized that you can’t have everything. Pierre’s bike is set up to work at racing speeds, and when he’s flying, his bike hits the ground with a helluva thud. Consequently, the suspension on his machinery has to be set up to handle the worst, and that explains the harsh ride at slow speeds.
PRINCIPLES OF FUNCTION
So, after realizing that gassing it was the answer, I gassed it. At a speed that I considered borderline safe, the machine smoothed out and began to feel neat.
Soon, I must admit, for the first time in my life I began looking for the roughest lines on the track, just to see what would happen. I particularly looked for holes and such on the straights, where I could really wail. Let me tell you, the bigger the bump and the faster the speed, the better the Monoshock feels. It’s uncanny.
Obviously there must be a limit to the suspension; but I never found it. The reason is simple. The Monoshock is capable of negotiating rough terrain faster than my mind was willing to admit. Let me put it another way. On any other machine I’ve ever ridden, the combination of bumps at the speed I was traveling would have meant a guaranteed trip over the bars. And when that’s the case, my mind forces me to gas it in stages, until the machine proves itself and ultimately reveals its limit. Enough said.
The Monoshock Yamaha is quick through the bumps, but that isn’t the only reason that Karsmakers and others have been winning on it. Read on.
The thing steers like a Maico. It’s a bike that you can dive under others on, and it will hold a line. The Monoshock made squaring off turns really easy, as well, and when I gassed it onto a straight, it literally exploded toward the next turn.
Wheft it comes on the pipe, it’s a lot like a CR Honda. You just grab gears as fast as you can and hold on. But when
the engine is just below the point of developing maximum power, it is completely different. On occasions when CRs will blubber and load up (like coming out of a turn in too high a gear), the works Yam pulls; only not quite as strongly. I found that I really had to blow it to make the engine falter.
Like the acceleration, braking is super. Pedal and lever pressure are slight and the feel is good, so it’s easy to avoid locking up a wheel. Riders of some Yamaha production bikes would be a lot happier if their brakes were half as good.
Now for the big question. How doS^r the 250 works Monoshock compare to a stock YZ? Powerwise, the Monoshock has more mid range and more top end. The Monoshock’s ride at slow speed is slightly harsher, but is smoother at racing speeds. The Monoshock is vastly superior when the going gets tough, due to greater rear suspension travel.
As far as steering goes, the stock YZ will hold just as tight a line, but the Monoshock does not exhibit the Stocker’s tendency to high side during a sideways slide over choppy terrain. Both machines are good for squaring off turns, although better-shaped bars on the Monoshock made the maneuver easier for me on that machine.
Soften up the ride a tad, and I’d pick the works bike over a stock YZ anytime, for any riding occasion (parts pricing excluded!). Wonder if I’ll be abl^^ to say the same thing when we’re al^^ riding Monoshocks and the shoes are onto something else. R5]
