I'd like to put the LS650 engine into an ol' skool hardtail springer project. Do you all think a very short and lightweight exhaust pipe with an internal baffle will be solid enough on its own without any other mounting points, like in the first pic of the shorty?

David Roy at Voodoo Vintage told me of the "free-floating" exhausts he's built for the 650, "We've never had one rip out the studs.  I believe your pipes would bend or crack before doing that.  Unless you had some weak stud bolts."

But I'm looking for some confirmation from you guys.  Seems maybe a lightweight short pipe would survive better than a long pipe.

not sure I would like dumping the exhaust into my pant leg.

I don't think I would trust it to not break the bolts. It might not be heavy but it does act like a lever on the bolts. They may fatigue under stress and break.

I agree that the pipe would fail before the bolts would. If you're really concerned about this then you could put a brace on the down tube.

Yeah, for practical purposes--such as not setting my pants on fire--I like Scoundrelz exhaust best, too.

I talked to Bob at Windsor Cycles yesterday about the flange bolt question, and he said a short pipe of a pound or even pound and a half probably wouldn't break or strip out the bolts.  However, he also said my bigger concern should be all the vibration produced by a big single eventually doing it anyway.  

Still, Scoundrelz exhaust would make positioning the engine in the frame such a cinch that I'm actually kind of tempted to try it anyhow...