I see Rotax has a new 135 HP engine the Rotax 915.
4 Cylinder fuel injected turbocharged with intercooler and typical reduction gearbox.
At 185 lbs, the 915 iS weighs about 35 lbs more than the 912 iS Sport.
Available in 2017.

Video link:
http://www.avweb.com/videos/Video-Rotax-Introduces-the-915-iS-224498-1.html

Maybe something to stick into the Bearhawk Patrol, Bearhawk LSA, or the Just Aircraft SuperSTOL XL.

Or slip it in a Wittman Tailwind for the ultimate ecosipper.

Rotax even had a 300HP V6 It never went into production. I hope someday they do that one.

Pretty heavy.....and pretty large in size what with all that extra crap. A clean paper design may be better for it, I sure don't want, or need, one in the S-7. Good to see the boys in Austria are burning the midnight oil though.

Courierguy wrote:

Pretty heavy....

At 185 pounds for a 135HP blown motor with reduction gearbox, I am in the grey area . From the Bearhawkin website http://www.bearhawkin.com/FAQ-Engines.html the following figures for some Lycoming powerplants.

Model Comp. Ratio HP RPM Weight
O-320-A,E 7.00:1 150 2700 244
O-320-B,D 8.50:1 160 2700 255
O-320-H 9.00:1 160 2700 253
IO-320-B,C 8.50:1 160 2700 259

Model Comp. Ratio HP RPM Weight
O-360-A 8.50:1 180 2700 269
O-360-E 9.00:1 180 2700 269
O-360-F 8.50:1 180 2700 270
IO-360-B 8.50:1 180 2700 270
IO-360-A,C 8.70:1 200 2700 293


At 8.50 Comp. Ratio Mogas is probably going to be okay. So pounds-horsepower comparisons are 185lbs-135HP, 255lbs-160HP, & 269lbs-180 HP

I think I’ll crack open another Budweiser, and think about it more. Yeah a totally clean design would have been great. I read that a lot of their engines go into US Military apps (drones, UAVs) and that the testing and qualification process is really tedious. Maybe that's one reason for sticking with a legacy design

I think you hit the nail on the head. My dad went to the Rotax maintenance school last winter. There were 2 guys there attending who work on UAV's. He said they were super good dudes and extremely tight -lipped. They did tell him that the cost of the engine was insignificant in comparison to the gear on board.