Hahn Racecraft Suzuki Gsx-R1117
HAHN RACECRAFT SUZUKI GSX-R1117
The real Chicago Bull
FOR YEARS, BILL HAHN HAS PUT THE QUICKEST GASOLINEpowered motorcycles into the record books at ProStar drag races, and the HRC GSX-R1117 turbo represents the culmination of his racing research.
That’s saying plenty.
The Hahn Suzuki is simply the hardest-running street-bike Cycle World has ever tested. Hardware such as Falicon knife-edge connecting rods, Hahn Racecraft forged 10.0:1 pistons and a Star Performance Parts cylinder head works with software that rivals the electronics of a factory Superbike effort.
The Hahn team relies on a laptop computer to download onboard diagnostics gained by a DynaTech Datalog recorder that monitors 16 functions. Dyna electronics take care of ignition advance and boost retard, plus control the rev limiter and dash-mounted shift light. HRC’s latest development, the Staged Injection System, allows the bike to idle cleanly and run at low rpm using the primary injector in each 46mm throttle body, while high-rpm and larger throttle openings cue the EFI computer to bring the secondary injectors into play.
This two-injector system works in conjunction with Hahn’s Electric Boost Controller, a switch that selects the amount of boost the Mitsubishi turbo’s wastegate allows to build, offering a variety of power levels depending upon conditions and fuel octane. The team could preset the boost controller to add power gradually at the dragstrip, or the rider could choose his poison by manipulating the tumsignal switch to choose between low, medium and high boost.
Even though the team has limited roadracing experience, it knew enough to fit a Fox shock and an SRS link out back. A sprinkling of Yoyodyne titanium fasteners lightened the Suzuki, and the additional weight of the intercooled turbo system was partially offset with Air-Tech fiberglass fuel tank and bodywork, and Performance Machine wheels shod with Michelin TX15s and 25s. Pingel chipped in with a high-flow petcock, as well as the air-shifter system and breather catch cans.
This bike dominated XS’s straight-line testing and got more than passing grades on the street and roadracing track. HRC delivered a bike that, apart from its rule-bending fender headlight, could truly survive on the street. In fact, the rear seat and passenger pegs are in place to give Kent Stotz’s wife a place to sit on Sundays. -Nick Ienatsch
Hahn Racecraft, 1981 D Wies brook Dr., Oswego, IL 60543; 630/801-1417
