I'm toying with the idea of forcing a rotary into a dirt bike frame. Any idea what engine I should go for?
Yes i know it will take a lot of fabrication.

 

Well, most of the dirt bikes I have seen weigh under 200 LBs, so by putting in a rotary you are basically doubling its weight. That is probably the most important thing to consider.

Another issue is that the rotary is dimensionally basically a box, while the frame is designed to hold an engine which is much flatter.

Keeping those two things in mind, I think the "best" rotary for a dirt bike application would be a custom single rotor unit made from 13B parts. Atkins sells a single rotor eccentric shaft should you want to do this.

 

If you have deep pockets, try these people: http://www.rotamax.net/

 

on a dirt bike huh? thats new lol post pics if you get it up and running

 

Well between rotomax and a few other companies I'm now toying with the very real possibility of a sub 200lb dirt bike with at least that much power. I'm just trying to figure out how i'd ever be able to repay the bank loans I'd need to build them....

http://www.aixro.de/

http://www.italsistem.com/saetta-eng.htm

http://thekneeslider.com/archives/20...r-motorcycles/

 

arctic cat made a rotary powered snowmobile i think its a 303 cc maybe u can fit that into a dirtbike

 

Yeah, I forgot about those. Sachs made several small rotary engines for snowmobiles, lawnmowers, etc.

 

Hey how about a re5 suzuki you can pick up the hole bike at a swap meet pretty cheap. I could have bought 3 last year for 700 they needed a lot of work but motors were complete.

 

Hmmm how do the power to weight ratios on either of those stack up against a 125cc two stroke?

edit: i saw that the sachs is pushing about 17 hp and the re5 has 63 but im having trouble finding the weight of the motors. anybody have any info?

 

i would love to see a rotary bike

 

whats wrong with a regular two stroke 250cc bike engine? ts ts

u may aswell get a ktm 380sx engine if you want some crazy power

 

Here's two for you.

My RE5 and a Hercules I've been cleaning up.

 

Too heavy and too physically bulky for a bike that'd fit me well.