Sorry for talking to myself here, but I called Dave Atkins, and got answers to most of my questions.  I’m actually getting pretty excited about this, but it will never work for the Airbike.  I’ll keep thinking.

 

If you had to make an estimate, what would a stock block weigh, in single rotor configuration?   By this, I mean with iron housings, and no water pump, flywheel, intakes etc.  Since a normal 13B block weighs about 190 lb, I’m guessing this would be around 110 lb. 

 

I was right- 110 for the block.  Lucky guess :-)

 

How much lighter are the aluminum side housings?

 

Don’t know, but Dave doesn’t really recommend them.  I didn’t ask for the full explanation, but it sounds like they don’t hold up too well.

 

How much HP could you make in direct drive mode, at say 3500 rpm. 

 

At 4000, the dyno plotted 50.6 hp, and 66 ft/lb torque. 

 

Does anyone currently offer eccentric shafts for a single rotor conversion?  I know Atkins made some, as did others probably.  Could you modify a two rotor shaft, or would it have to be made from scratch? 

 

Atkins sells complete single rotor engines for $4595 (carb), or $6500 (FI).  They also sell the eccentric shaft kit for $1295.  The kit is a shaft they make themselves, a rotor, and counterweights, all balanced as an assembly.  Sounds like everything else is off the shelf Mazda parts, except for the obvious things like oil pans, manifolds, etc. 

 

He’s even got a couple of companies working on lightweight belt drives, so there could be a very viable single rotor engine on the market very soon. 

 

Pretty cool.  I should call Dave more often :-)

 

Rusty