He said, "It don't mean ANYTHING unless it has a red arc to tell you when its to the overheating point."

So, if anyone has any info, I'll rub it in his face. But I think my gauge isn't a dumb thing at all.

ORIGINAL: 1200c

Dino oil will breakdown after about 250 degrees, while a good synthetic oil will breakdown after about 300 degrees. So for dino oil the oil is overheated after 250 degrees, but the engine is still doing fine.

That is exactly the kind of info I was looking for. Oil overheating temp is good enough for me. Thanks 1200c.

As the accompanying chart indicates, the oil oxidation rate increases explosively above 250 degrees for fossil oil like that recommended by Harley. At 270 degrees, a mere 20 degrees above the 250-degree limit, the oxidation rate doubles, thereby reducing the life of the oil by half. Sustained riding at over 300 degrees reduces oil life by 80 percent.

Now don't flip out if the temperature rises above these figures for a short period of time, but change the oil if you're in doubt.

Living here in the tundra I was thinking about getting an oil heater, I don't think those guages go into the negitive numbers do they? does oil still flow at -40 in a Harley? f**k I hate the cold!