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/720681
FEATURE TRIUMPH INFOR ROCKET STREAMLINER P96 THE BONES "T he Triumph Stream- liner has a carbon Kevlar monocoque, which is oven-baked in an autoclave, using pre-preg material. I was personally responsible for the overall packaging, the overall design, and the overall layout, but I had sup- port from others with FEA [Finite Element Analysis] to optimize the plys and everything. The frontal area of the vehicle is basically determined by the engines, and these are big engines. So we basically packaged these in as small a diameter structure as we could, and then the driver fits in front of that. "There are two issues you address in designing a vehicle to go fast in: speed, and safety. I've watched many videos of other streamliners crashing, and what happens is that they tip over, then slide along on their side for a little while, until a body panel flies off. As soon as that happens you get a sharp edge, and it digs in and tumbles, or else pencil rolls. To me, the monocoque was such a natural way to get the surface structure smoothed out to where if it hits, it's not compromised. Carbon fiber is just so amazing in terms of stiffness to weight. Our basic monocoque tub weighs less than 400 pounds. Okay, light weight is not necessarily an advan- tage on the sant, because you want weight for traction, but it's an advantage for us because we can position the weight where we want it. The monocoque structure gives us a great advantage in strength, safety and aerodynamics. All of the panels that are detachable A full monocoque chassis means there's little chance of the Triumph breaking up in a crash. Between the wheels, the streamliner is as stiff as a MotoGP machine. are perimeter bolted, so everything is as strong as everything else. Our FEA shows us that this vehicle can bounce along at 40g without destructing, and the driver can take 25g before he is compromised. "We did three basic parts to the computational analysis for this project, so besides FEA for the structure, we did a lot of CFD for the aerody- namics, and then we also did a regular motorcycle stability analysis. Perhaps surpris- ingly, it was difficult to find anyone who could do this, and the only company I could find to do so was in Italy, called DinaMoto. They do a lot of work on MotoGP bikes. Their program is called FastBike3D, and the analysis showed that we had to rebalance a lot of things. The results came back that this thing we'd designed was going to go into a weave mode at 250 mph, which was no good at all! So we had to shift some weight around and stiffen the chassis. They tell us that despite its long 14-foot wheelbase, our Triumph Streamliner is as stiff between the wheels as a MotoGP bike, which is excellent."