[jf_15]

Hi all,
1) Optimum engine temp? Has anyone got anything proven to see at what temp this engine performs at its peak?

[BrianZ]

the rotax manual has optimum at 65 C, maximum at 85, and minumum at 45.
that's for mini, junior, and senior.

for micromax optimum is 75 C, min 45, and max 90.

ive always felt that with the senior once it is better to keep it at around 60-65 if you can. The more above 65 it goes the more it seems to lose.

now if the rotax manual and a dyno would agree i don't know.

[fastenurseatbelts125]

would the optium temp b different if it is has the restricter in it?

[gp8]

Optimum on a JMax is 50 - 55 according to the dyno with a slight drop off below this level down to 45 and a slightly greater rate drop off up to 65. The engines drop away quite a bit above 65. Of course keeping your engine under 55 whilst racing in Malaysia or on a 40+ degree day in Australia is challenging...

I presume that the optimum temps for Snr and Micro will be similar.