My oil gets hot enough as it is, I wouldn't run mine without at least some kind of cooler. The old twins had an oil tank that allowed the oil to cool ours is in the bottom of the engine where it really doesn't get a chance to cool. I don't think it would be too hard to make that $89 cooler work without buying any kit, just have to make a fitting or 2 probably.

I learned all I need to know about life by killing smart people and eating their brains.
Eat right ,Exercise ,Stay fit, Die Anyway!