| BIG
GUNS IN TOWN About eight years ago perennial Canadian Pro Drag champ Chris Gartman was busy working in the shop with longtime friend and crewmember, Dave Rode, when Rode, lost in thought, suddenly surfaced from his reverie to announce that the engine was "in the wrong place." From then on designing a chassis that would fix a drag racing engine at the "correct" end of the bike became Rode's focus. And, during the course of the 2001 Canadian Motorcycle Drag Racing Associate season Gartman and Rode finally introduced to fans the world's first competitive Top Fuel/Pro Fuel rear engine Harley. Call it Project Big Guns and if it works the way Surrey, BC - based Gartman and Rode hope, drag racers can expect new levels of safety and performance. By mounting the engine at the back of the bike, there are at last three things happening right off the bat. The rider's position changes as he slides further to the front. Now, rather than being splayed-out over top of the power plant, he's sitting closer to the handlebars and putting more weight on the critical steering areas. "Approximately 20 per cent more weight on the front wheel," says Gartman, "than a conventional drag bike." This is a crucial gain because Top Fuel machines, especially, are notoriously unresponsive to steering inputs and with a wheelbase of more than 100 inches, you want every extra bit of handling you can get. The second mechanical advantage arrives at the back of the bike as a traction bonus. Big Guns runs an abbreviated driveline that features an open clutch mounted directly on the engine sprocket shaft. Ditching the primary creates a more direct power transfer and that means goodbye wheel spin, hello more consistent hook up when the rider really gets on the throttle. This set-up should allow the Top Fuel guys to mount smaller rear wheels sharply reducing the "steam roller effect" of running giant hoops, while the engine placement itself addresses weight transfer issues - with a conventional arrangement a hard crack of throttle at the start line not only sends the front wheel clawing at the sky but also tends to partially unload the back wheel while rocking the Top Fueler back onto the wheelie bar. And that folks, isn't good for anybody's ET. The third (and arguably) most important gain from the Big Gun's concept is safety. Too many times fans have witnessed a Top Fueler grenade in mid-pass and what happens nxt doesn't need explaining. With the engine in the back, though, even if heads do erupt the shrapnel blows behind the rider, not through him. However, Gartman says that during the 29 runs he's made with the prototype he took to wearing his armored chest protector in the back just in case. By the way, during this experimental time some of the numbers they've been clocking have given them plenty of reason to be optimistic including a 7.37 second pass in the quarter mile at 178 mph. There have been some early development problems, though. "The bike handles like a dream, but we haven't been able to keep the candles lit past the 1,200-foot mark," says Gartman. But, these are technicalities more to with sorting out the engine than with the actual design of the frame. Whether or not they actually are related remains to be seen. Currently Rode and Garman have a liberty Machine-built 150 cu. in. Fast Cat engine outputting 600 horses in the Big Guns chromoly frame. With a 104-ince wheelbase carrying 560 pounds plus rider, the machine is led onto the track by an inverted Kosman front end and trailed by a 12 X 29 - inch Goodyear Eagle car tire. Gartman says one of the other benefits has been that the open design of the clutch allows dust to blow free and dramatically shortens maintenance times during those frantic between-runs pit times. "During the last weekend in Vegas, we didn't have to disassemble the clutch even once," he said, "and 1.16-60 fts. Not bad!" And, in a sport where
costs are high and returns sometimes not so high, sponsorship is critical.
Herein lies yet another benefit of bringing the engine to the back: more
body panel space, which equals more room to tack on sponsor slogans. That
can't hurt either. |