red light manifold pressure ?
fairly newish Stemme S12 (83'wing span self luanch glider) propelled by a Rotax turbo charged 914. 100hours so far on the engine and not making 100% of the orginal RPM currenttly only making 5300 at max throttle setting ,remembreing uppward of 6200-6400 a couple of years back when new . After a 5-10 minute climb to 3-4000' 5300 rpm I will see a red lite on the manifold pressure ( assuming it is a high pressure indication) pulling the throttle back a tad (loose 100rpm or so) seems to cure the lite (turns off), We've used only 100LL . Any suggestions to get the power back to normal would be great.