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/126504
00 CJ') Ron Knapp preperee hIa Velvet Screamer for • OO/G•• record run. The EEiG designation was incorrectly .pplied during. tech inspection. Ron Knapp and the Velvet Scream A high pitched screech fills your eardrums - it penetrates your whole body, the stacatto barks trying to invade every pore. In the pits, surrounded by 50 other dragsters, it can be heard above illl others. It stands out, like Don Rickles in a convent. Tuner Gene Schroeder gives the throttle a few whaps. The rpms turned by the motor are high enough to scatter the innards of most racing machines - but it's still well below the powerband of this four cylinder ,slingshot. Where J1lOlIt motors come unglued at 11 thou, this one hiu the powerband - and continues pulling up towards the 16,000 range.. Ron Knapp swings himself over the creation - a monster of his own design' and assembly. His feet reach the 'pegs - way back by the rear axle and wheelie bars. His racer·size 5'5" frame is jUJt barely long enough. He has to stretch out almost horizontally to ..~ dJ¢ tlipAP. 'babdleba......An..iI\· dication of the meticulous detailing is the front brake lever that wraps behind two fingers - it's anodized and polished. Below his chest is the powerplant that has propelled Ron Knapp down the quaner·inile to snag five National records at the finish lights. What staned out as "an idea and some garage space" has turned into one of the most successful two-stroke drag racing machines in years. The machine's power codl.es from an old road racing motor - a TZ700 that was later bored out to the more current TZ750 specifications. Knapp figured that the transition from the high banks of Daytona to the flat drag strips of California and other states WQUN'.be. ·aimple·.fQ'l·..tb..·~·.He even surprised himself at how well the engine adapted to its new duties as a drag strip burner. The entire cooling system was removed or 'highly modified. The water pump was pitched. The oil pump found home in a long forgotten box. The water jackets were gutted out to allow air flow when zinging down the strip. The cylinders were "cleaned up," Bassani deSigned the exhaust pipes and Raimes Engineering adapted a set of RD400F cylinder heads. Until just recently the bike was run on the standard 34mm Mikuni carbs (they've since switched to Lectron). Inside the gear· box first and sixth gears were removed since the engine in stock trim had enough torque to pull second from a standing stan, and would most likely flyaway to the next county if you ever got into sixth gear and wound it out. Since you can't just drop by your local dealer and order a drag racing frame, Knapp turned to the team of Herman Booi. a car dragster frame designer, and Larry Maddox .wtio owns Hemet Cycle. They came up with the combination that keeps everything under dead aim accuracy even in the upper hundreds range. Some bikes have been touted as so smooth "they're riding on rails." If so, then Knapp's m.achine has a laser·beam·thin guide WIre. After the frame was bent, cut and welded, it went to Ensenada Chrome to be nickIe plated. Lou of parts went to Jenco Plating for anodizing. Knapp uses the standard TZ brake system, but he bought Magnesium Morris tnags and Goodyear racing slicks to round out the package. Mer getting it all wrapped together and running "smooth but not quite dialed-in" Knapp went to Carlsbad for the Dragbike race. Competing in the DO/Gas class he broke the existing national record with a blistering 9.29 seconds at 142.87 mph. The fastest and quickest - a normally aspirated two stroke had ever gone. This created quite a stir in the pits. It's~oeverydayd1at-lOIDdMMly COIDCS