Thanks again everyone. So general opinions are mild steel dom tube, good point zooterincm at least I can mig a mild steel frame if something does go wrong. Grumm441 I am running a late model 600cc triumph daytona engine with a turbo to put me in blown class.
Greaseball,
Sorry I'm a little late to respond on this thread, but I wanted to chime in; I've had experience with both 1" x .062"wall 1020 CREW (which broke) as well as chrome moly (which hasn't - - yet!). Don't let chrome moly scare you away. As Neil has stated, thin walled normalized Chrome moly tubing does not require pre or post heating, can be welded by oxy-acetylene or TIG, and is at least 25% stronger than mild steel. The important thing is to either know how to weld or to use a welder who does, but that applies to whatever tubing you choose.
The design of your chassis is just as important as the material. I doubt that many on this forum have built a bike with a 10' wheelbase and 200 hp. You're going to be in 200 mph territory (if I had 200 hp, my bike would be capable of about 236 mph) and your chassis is twice as long as a standard bike which means stresses are going to be doubled as well. Consider showing your design to a structural engineer for ideas, but don't expect any engineer to sign off - - because they probably won't (can't because of their code of ethics which prevents them from designing in a field in which they are not qualified.) But they may be able to give you some valuable pointers.
Tom
