Hi to all concerned with this debate..Rotax make and design the engine to a specification to deliver the required power output,max and cruise and to obtain the specified TBO without any failures.This output is Dyno performance and they are not really concerned with what aircraft you have or your frugal attempts to reduce fuel consumption or cruise speeds.There is to many varied designs of aircraft,draggy ones and slippery ones.Rotax publish recommendations to cover the best for their engines and its up to the manufacturer or operator to use this or apply their own and except the consquences.
Whilst Rotax manufacture the engine the ultimate responcibility of performance etc is the aircraft manufacturer.Whilst the max limit is 6800 RPM for 5 min the 582 is robust enough to over prop and under prop and still do the job,depending on the propeller you have fitted..
We set the Austflight drifter 582 strut brace with 4 blade Brolga prop with 17degree pitch blocks to obtain 6420RPM static which related to about 6550 climb out and 6800/6900 full throttle straight and level and advised owners after reaching a safe height on take off to then reduce Rpm back to around 6200..
Rotax fuel the engine to assist cooling of the combustion chamber during full power and yes it uses a lot of fuel,but it is the safety valve,if you dont use full power on take off and resist pulling back on the throttle to early,this is when the dredded piston siezure occurs.Your life is worth more than a little less of fuel.. I have seen a lot of engine prop combinations over the years and this 582 engine can handle a lot of punishment but it is still a 2 stroke engine and as such is subject to design/operator limitations.Since unleaded fuel and better oils come on the market we have very little problems with the 582 and my customers regulary obtain 600 hrs between overhauls with no decarboning and only carby maintenance,regular servicing etc,no opening of the engine..