Keeping your DC motor cool

[Jim]

I own a 2007 Zenn NEV with a stock 5 HP direct current motor made by Advanced DC. This motor, and others I have read about, tend to overheat after a few thousand miles. I know I could install a higher horsepower motor in my Zenn, but there are a lot of issues in doing so (the higher horsepower motor may overheat too, the mounting flange must be re-drilled to match the mounting holes in the Zenn tranaxle and this voids the motor warranty, the speedometer display may not display the correct speed, and the motor temperature  gage on the dash may not display the correct temperature).

What I am trying to find out is this: Is there a simple mod I could do to the motor to make it run cooler? Some people have suggested installing a cooling fan and/or cooling fins.

What do you folks suggest?

Thanks.