When I had my 2006 Ultra Classic and my 88 engine, I used to measure about 220 degrees with my LCD oil dipstick. On a hot day running around town, I might get to 240. After I got my 2011 RG Ultra with the 103 engine, I noticed the temps were higher. I see at least 240 degrees. But I usually see higher temps than that on the LCD oil dipstick. When I got off the Interstate riding at about 65 mph for awhile and the outside temperature was in the low 90s, the LCD oil dipstick read 270 degrees. Sometimes when I'm riding around town, the LCD dipstick gets so hot it quits working. If I stop at a string of 3 or 4 red lights, my engine goes in the cooling mode at idle. The dealership says it's normal for a 103 engine.

So what is too hot? Some say you can damage your engine if you run it too hot. So what is that temperature?

 

Synthetic breaks down at 300 and "I THINK" conventional at 250 so stay as far below those numbers as you can.