flex shaft

What is an acceptable temperature for the flex shaft. I expect some heat

Mine generally runs warm to the touch but not hot enough to burn me.

I look for 10 to 20 deg above room temp.

Per the new instruction posted: http://forum.carvewright.com/attachm...0&d=1314304046

Not to be over 158 Fahrenheit.

That seems awfully warm to me. I don't think either of mine have been above 105-110... and I'd say 102 is about my norm.

I'm just repeating what the engineers said. It is "not to go over", so I'm not sure what normal range would be.