I always thought heat was the biggest problem those V.R.s had (the heat they dissipated doing their job, not ambient temp they live in). Every V.R. I've tried, two Ducattis and, I think, three different J.D.s, have run too hot to touch. What I'm trying now is to mount a small computer cooling fan I had lying about directly to the V.R. I actually tie-wrapped it directly to the cooling fins, blowing air up into the fins. So far, the two V.R.s I've tried that both ran really cool. I guess we'll see how well the J.D. I have in now lasts.
Port Orange, Fl
RV-12 N121TK ELSA #120845; first flight 06/10/2015
RV-12 N918EN ELSA #120995 Eagles Nest Project; first flight 05/18/2019
SPA Panther N26TK in progress