Cycle News - Archive Issues - 1980's

E MIKUNI"POWER-JEr CARBURETORS... e~~D@G~~~~'-?~ for off-road motorcycles TZ7OO-be.ed motor hila a powerlHtncl between 10.000 and 16.000 rpm. along with so bizarre a creature and blows the shorts off the established heroes. Knapp rubbed it in even farther the next day. He added 20% alcohol to his mixture of gas and Yamalube, ran his bike in the DO/Fuel class and broke another ET record, going 9.59 and missing the class top speed record by a scant two tenths of an mph. "The bike was a little tired from the record the day before," explained Ron, "so we didn't push it as much as when we got the DO/Gas title. Since it hadn't heen raced before we didn't know what it looked like inside, so we had no idea how durable it was. Turns out it's dependable as the sun." Knapp came back later in the year to prove that he was consistent, too. At Fremont Raceway during an IDBA event he again broke records in the DD/Gas class with an ET of 9.49 at 142 mph. And whether or not it's the perfectionist coming out, Knapp still insists that it isn't nearing maximum potential yet. To see and hear his machine run down the strip is an experience different from anything else in drag racing short of a rocket car. Unlike another Yamaha rider, Ron Teson and his XS11, Knapp and his TZ don't thunder down the strip - they screech. One minute they're sitting dead still at the Christmas tree, and then ... they're just gone. It will take you longer to read this sentence than it takes Knapp and his Yamaha dragner to go from a standing start to 140 mph. When all four of the TZ's cylinders get up to steam the bike pumps out gobs of horsepowe.r. The powerband starts - starts mind you - at 10,000 rpm. Knapp has to feather the clutch out slowly at the start - or else the motor tries to leap out of the frame if it gets too much traction, or burns the tire to a frazzle if it breaks loose. The wheelie bar on back twists and contorts for the first 20 feet as things start hooking up and accelerating. The TZ lofts the front wheel in second gear. It keeps it up in third gear. When Knapp shifts froni third to fourth the wheel drops back to the grounds - for a few milliseconds, then leaps back up in the air. On the average run Ron Knapp has the front wheel on the ground only in fifth gear. From dead stopped to well over 100 mph, he's doing the world's fastest and quickest wheelie - and still screwing the throttle wide open for more. The motor sounds like something released from a cage. When he opens • .,t~jl~~Cbf'\IP-oaw.y ...,. from something. It screams all the way down the dragstrip. The sound is so penetrating and high pitched that it's hard to listen and hear the bike shift. Knapp's version of the ride from behind the bars is one of quickness and blurs. "The ground blurs, my arms get pulled and I have to work at pushing the button for the air shifter. It revs so fast that I have to keep one eye on the tach and the other on the strip. When I shut off it's like hitting a brick wall. All the force, the pull and acceleration stops pushing down on my body. Then I realIZe what normal is like and get a lot of respect for the amount of horsepower it's putting out. It's a piece of . equipment that I really have tons of respect for - it could get pretty nasty." Knapp feels that the ride is much more pleasant than the four stroke drag racers. "I don't feel any vibration once we're underway" he says, "but I think I do have the advantage when it comes to feeling how the bike is working through the bars. Even the littlest vibration will come through and you can track it down. The big four strokes don't have that sensitive feel. My bike is unique - in lots of ways. It's also a real thrill to ride. The experience of going that fast and accelerating that hard is just something you can't get anywhere else." When he's not out racing on the circuit, Ron Knapp has a job that keeps him up to his elbows in motorcycles. He's a District Sales Representative for Yamaha, working with dealer sales and special promotions. Handling 50 dealerships and racing at the same time keeps Knapp busy. But there's always time to get his bike out (thanks to his sponsors Mission Viejo Yamaha, Eagle I Oil and ND spark plugs) and show up from nowhere to demolish another National record. Knapp, who lives with his wife and son in Hacienda Heights, is no newcomer to drag racing - he's been doing it for 20 yean. But when he dreamed up the combination of the Yamaha TZ motor and drag racing he hit on a winning combination that will undoubtedly keep him dominating the DO/Gas class for a long time. • (Since this article was written, Ron Knapp h4s set a new IDBA. record in the DD/Gas class at 9.20 seconds and HJ.6Jmph. His plans/or 19811 "We plan to break into the tights at OWT 1 JOmph." &clcing Knapp in his wnture are Mission Viejo Yamaha, Eagle 1 Oil, ND Spar. Plugs, JtfI&O PlGtiftg, TitM Strt and Ltctron... ..BtJitor~f.." ",". "........ <0...1'" ~.. t- ,',,', Power Nozzle Avllllable In Sizes VM34, VM36 AND VM38 Mikuni does it again! Used for years by pro-racers, the Mikuni need it most! Power-Jet is now available to Mikuni Power-Jet carbs are you too. This unique system built to a standard of quality boosts engine power when you unequalled in the industry. £lmJ!1jJJ AMERICAN CORPORArlON 8910 Mikuni Avenue, Northrirlge, CA 91324 (213) 873-2101 Please send me ( ) of those red T-shirts in the sizes checked below. I've enclosed $6.95 for each WDCHTHTDIIC shirt. ( ISm. ( ) Med. ( ILg. ( ) XL Indicate the number of shirts you need in the parentheses by the proper size. Nemel _ Add'ess _ Stete City Zlp, _ Cycle News Products. P.O. Box 498. Long Be.ch. 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