I am running prototype aluminum heat sink soft mounts with Pletty 30-10 Evo's in my two Leviosa's, with cut-nose spinners. Removing the nose of the spinners lowered the motor outer can temps by ~ 25 deg F, and the addition of the heat sink mount lowered it another 20 deg F, to ~ 130-135 deg F (from a Masters flight flown in hot, 100 deg F, windy weather). Interestingly, I measured the temp of the heat sink motor plate after a typical flight at ~ 145 deg F, which was 10 - 15 deg F WARMER than the motor case! I also measured the temp of the rear motor mounting screws and they were about the same as the temp of the heat sink plate (normally they're much hotter than that), so there's a lot of thermal heat transfer from the motor core into the heat sink plate.

BTW - The origination of the cut-off spinner nose was initially tested last fall by SoCal Advanced class pilot Mike Greear. I'm not sure where the idea came from, possibly an extension of Jim Oddino's successful use of an undersized spinner on his Abbra over the last couple of years (which also works well). I do remember a discussion last year with Greg Frohreich about the idea, but don't recall if it was his concept or Mike's.