Two strokes
Sir, If you have a large hangar door the 582 performs well as a door stop..I have flown most engines in trikes. As previous threads will tell you the 912 has 1500 hrs TBO, the 582 will require crank replacement after 350-400 hrs. The fuel consumption is probably double, sure they do have nice performance. But if you live at low altitude fly a lot on your own; other less expensive options exist with 4 strokes as well..Take a look at the HKS 700e (60 hp), Verner boxer twin (80 hp) and Verner radials. Maybe the Jabiru is an option also..
For info my first 582 popped at 190 hrs and the second one at 380 hrs, that was enough for me. I couldnt justify the 912 as we use the trike as a test bed for avionics so it gets a lot of short trips. Fuel consumption and reliability was the main choice. I installed the HKS 700 e it gives me solo 900 fpm and dual 600fpm with fuel burn solo 6 litres an hour dual 9,5 ltrs maximum. At 200 hrs now just changed the plugs, starts first time, no problems at all. BUT it has oil in it !!
The 503 incidentally is not a bad option, they seem to last longer..still two stroke. Here in South Africa we have lost a few people with 2 strokes, the tendency in Johannesburg is to use the 582 as its 6,000 feet, two strokes definitely lose less power with altitude.
Hope this helps a bit.
Cheers Paul