best 100 HP auto/motorcycle engine conversion?

[stanislavz]

You likely have never been on a sled trip in the north country.

How does it look ? I have seen hill-climbing, it was kind of high tuned ones, and some do not survive..

 

[13brv3]

How much can a Onex take? A 912 is going to make it a rocket off the bat.

The Onex was originally intended for the 80HP Aerovee, but they also allowed the 100HP turbo version. They appear to support the UL350 which is up to 130HP. Sonex does support the 912 for some models, but they don't make a mount for the Onex. Prop diameter is a significant limitation.

I'd hope my 80HP 912 will be better than the average 80HP Aerovee, but it would be nice to have more power I bet.

 

[stanislavz]

80HP Aerovee, but it would be nice to have more power I bet.

Buy used rotax, with good bottom end, and give him a new set of high compression pistons. 750usd i think. All else same, gives you 90-95hp.

 

[stanislavz]

Sorry 850 usd. CONVERT YOUR ROTAX 912UL TO THE 93 HORSEPOWER FEEL THE SURGE OF ANOTHER 13 HORSEPOWER

They do have install manual too.

 

[TFF]

Wow. That’s a lot more powerful than the VWs I think about.

 

[120mm]

How does it look ? I have seen hill-climbing, it was kind of high tuned ones, and some do not survive..

Hours and hours of high load on rough surfaces at low speeds (mostly). I imagine the stresses are similar to WWI dogfighting.

 

[AIRCAB]

It sounds like a good deal if I needed the power. But I don't, and the AM13 appears more sorted. Still thinking a used O200 is a better deal, though I'm a sucker for an auto conversion

Have you ever had to buy certified aero engine parts ? You wont be happy !

 

[AIRCAB]

How does it look ? I have seen hill-climbing, it was kind of high tuned ones, and some do not survive..

It looks to me, that they tape the throttle wide open, and just hang on for a few hours till the next stop (break)

 

[120mm]

Have you ever had to buy certified aero engine parts ? You wont be happy !

I'm an A&P, so yeah.

Plus parts availability of that 1.3L engine is pretty amazing. Truly a global engine

 

[13brv3]

Figured it out, ignore.

 

[sotaro]

Yamaha Apex is about 170 lbs complete, with oil, radiator, exhaust, electric start, EFI gear reduction ready to run with more than 100 hp. Turbo versions are flying with much more power...The Yamaha Phaser is about 135 lbs same as above, ready to fly, 80 hp.

The Apex has about a dozen flying with cumulative (all examples) about less than a thousand hours in planes and trikes. Yamaha engines are flying, the RX-1, an older version of the Apex (both 4 cylinders), and the 3 cylinder version, mostly in trikes "With approximately 150 Yamahas out flying (as of 2019), some dating back 10 years now, we conservatively have 15,000 to 20,000 cumulative hours on Yamahas in the air, a number that is growing rapidly..." This was written July 2018 Facebook Groups The Phazer has a few flying with s few hours. Look on Facebook for more info

 

[Mitchell]

I’m putting a yamaha Apex in my project. I should have everything firewall foward done for about 10 grand. I looked at about everything before deciding to go with the Apex. The big reasons that stood out to me was the base engine is as bulletproof as they get in the snowmobile world. I also personally prefer yamaha engines over anything BRP makes including the 912. I wanted efi, liquid cooled “I live in Minnesota and want a good heater”, and light weight. I oversized the engine mount quite a bit but should still have a flying engine for under 180lbs installed. I also really liked how I could throttle back to still make that 100hp. Vs. a lot of the other options which make 100hp max

 

[rv7charlie]

The Onex was originally intended for the 80HP Aerovee, but they also allowed the 100HP turbo version. They appear to support the UL350 which is up to 130HP. Sonex does support the 912 for some models, but they don't make a mount for the Onex. Prop diameter is a significant limitation.

I'd hope my 80HP 912 will be better than the average 80HP Aerovee, but it would be nice to have more power I bet.

Aren't you going to have the same prop dia issues with the 80hp 912?

 

[13brv3]

Aren't you going to have the same prop dia issues with the 80hp 912?

It's not ideal, but manageable for 80 HP. More HP would likely require taller main gear.

 

[sotaro]

I’m putting a yamaha Apex in my project. I should have everything firewall foward done for about 10 grand. I looked at about everything before deciding to go with the Apex. The big reasons that stood out to me was the base engine is as bulletproof as they get in the snowmobile world. I also personally prefer yamaha engines over anything BRP makes including the 912. I wanted efi, liquid cooled “I live in Minnesota and want a good heater”, and light weight. I oversized the engine mount quite a bit but should still have a flying engine for under 180lbs installed. I also really liked how I could throttle back to still make that 100hp. Vs. a lot of the other options which make 100hp max

Would love to see your build blog when you can.

 

[SlowFlight]

Planning a RX-1, similar earlier motor at some point and would greatly value a build process choice.

 

[Yellowhammer]

Aka, the eternal search. Not yet found.


BJC

Best comment I have read in a while!

 

[Iwerk]

I purchased a pair of Honda 750VFR engines a few years ago. They use gear driven dual overhead cams.
I had thought about installing them in either a hovercraft or one of my aircraft projects.

Honda VFR750F - Wikipedia

en.wikipedia.org

 

[slociviccoupe]

All the guys screaming rx-1 please check and or replace the rod bolts. If they share same rods as the mr-1, or the r1 engine they like to sling rods from failed rod bolts. Yes i know there are many flying with no issues but you dont want to be the one that does. Ive seen engines go 2500 hours in a ski and ive seen one go at 100 hours. Ive never personally had one fail on me but have worked on enough of them that its worth rolling it over and checking torque or just replacing the bolts.

 

[AIRCAB]

I'm an A&P, so yeah.

Plus parts availability of that 1.3L engine is pretty amazing. Truly a global engine

Well in my direct experience, A+P mechanics do not buy parts, they are basically parts changers, condemning good, service parts to the scrap bin, then the customer has to buy the parts, mostly.