Cycle News - Archive Issues - 1980's

Cycle News 1980 04 30

Cycle News is a weekly magazine that covers all aspects of motorcycling including Supercross, Motocross and MotoGP as well as new motorcycles

Issue link: https://magazine.cyclenews.com/i/126467

Contents of this Issue

Navigation

Page 54 of 55

This is probably the best part about the 1T425G - the motor, It's got plenty of good. flexible power alweys ready, Impression: Yamaha IT425G Playbike, prospector or both forIS By Mark Kariya Yamaha's current advertising pushes their IT series of off-roaders as the thing to ride for those whose quest is ISDT gold. We can't fault that, but would like to add, judging by the IT425G in particular, that they might be just the ticket for someone looking for a dynamite piay. bike, too. The 425 seemed to be 14 equally at home plonking in first gear through a boulder-strewn stream bed or hO?king it in fifth across the desert, dodgmg rocks and puckerbushes_. Those accustomed to lean-looking I ~5cc motocrossers may. fin~ the 425 a bit rotund, but evc:rythlng IS there for a 'purpose, ofte~ bIgger or stronger to wll~tand the ngors of endurance offroadlng. T~e large, unbre~kabl~ YZ-type plastic fenders are whIte thIS year and the rear one with its small taillight an~ a tool bag especially seems a bit bulbous, but they do a good job keeping most of the muck down where it belongs. A capacity of 3.2 gallons (12 liters) of pre-mix does give the blue plastic tank more ample proportions. It also allows you to go about GO· 70 miles before switching to reserve. We always gassed it up at around 50 miles or so and spared ourselves the agony of wondering if reserve would carry us back to camp. Hopping aboard the bike is not an unpleasant experience thanks to the 36.8 inch seat height. The layout of all controls is good, though personal preference might dictate a set of narrower bars. With the pelcock on, the SSmm Mikuni's choke pressed down and the kickstart.lever swung out, we ki~ked it through Its.stroke..Thankfully, .t kicks through faIrly easdy; our 425 proved to be a reluctant starter when cold. When warmed up, one or two kicks did the trick, but when cold, the kicker got warmer a lot quicker than the enll;ine_ After starting it. the choke could be switched off almost immediately. The throttle response was quick, sort of a reminder of the motor's YZ heritage. One thing noticed right off the bat, though, was the large amount of mechanical clatter emanating from the 425cc mill. The note from the U.S. Forest Service-approved silencer/spark arrestor is a mere whisper in compari. son. There is an "Off· Road Riding Kit" that comes with the bike. We inserted some of its rubber noise absorbers between the cylinder fins, but that didn't reduce the noise much. Other items such as the silencer cap and choke pipe will quiet the exhaust note further. They also noticeably reduce power, so we declined using them. Waiting for things to get sufficiently warmed up, the saddle seems firm, but comfortable. It's unnoticed while riding and becomes more cushy with use. Underway for th~ first time, the im· mediate impression is of good power which further riding time confirms. A good test of both torque and hone- power is deep sand so we hauled the bike out to GIamis, an area in southern California's Imperial VaIIey near Yuma, Arizona that is nothing but sand dunes - a hotbed for buggies, three-wheelen and other sand toys. There, the 425 could buzz its way up the big dunes in third, sometimes fourth gear. It never lacked for horsepower, though a true sand freak would want to replace the 5.IOxl8 IRC Vulcanduro with a paddle tire. When it came to just cruising over the sand, the ample torque proved to be a pleasure to work with. Unless the revs got ridiculously low, the reed· valved engine never hesitated and we could control the amount of wheelspin with the thronle going up smaller dunes. Riding at night is possible with the small headlight, which even has high and low beams, but if you go much faster than third gear, you'll be overriding its effective range. It's mainly there to make the bike enduro-legal. Getting things stopped is made easy with typical Yamaha brakes housed in conical hubs front and rear. The front is fabulous, requiring two fingers and little effort on the dog-leg lever to retard speed quickly. In back, the rodoperated brake is powerful and most effective when there is prime traction, but seems to lock up and kill the motor a bit too easily on hills or in slick or loose stuff. More riding time seemed to improve the situation. To get an idea of the bike's performance in competition, we entered a basic SoCal club-type enduro held in the desert. One of the first things noticed was that the speedo was a little hard to read, but that may have been due to unfamiliarity with the unit. It is ~ot marked for each mile-per-hour Increment. The tripmeter on our bike was off by justl~ than \I.th of a mile under. It's easily resettable via a large plastic knob on the left side of the speedo housing. Having abundant power nearly everywhere in the scale proved to be a blessing, especially since it doesn't sneak up on you suddenly when coming out of a slick turn or when your feet are flailing wildly behind the bike after you get off balance going up a rocky uphill. The combination of quick throttle response and good power also helped in deep whoops where it was unnecessary to tug up on the bars to loft the front end. By staying up on the pegs and keeping your weight biased sIigbtIy to the rear, it was just a matter of giving the thronle a quick twist in order to bring the front end up and set it down where you pleased. In fact, it's one of the easiest bikes to wheelie that we've ridden. In those unexpected moments when flying down a trail and suddenly encountering a set of those big whoops, it was reassuring to know that the forks, with thdr nine inches of travel, would soak them up ably. Though they come equipped with air valves, Yamaha's service manual suggests running zero pressure in them so that's what we did. They worked well and kept abuse from fatiguing us prematu~e1y in the situations we ran into. The monoshock might need a little help, however. It was just on the harsh side when new. More riding time 100lleJled it up to the point where it almost felt too soft. Adjusting the preload and damping should help. It worked better on the medium-to-Iarge size bumps and we only used the full eight inches of travel occasionally. Making time through fut. straight-

Articles in this issue

Archives of this issue

view archives of Cycle News - Archive Issues - 1980's - Cycle News 1980 04 30