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Old 07-30-2009, 02:23 PM
Luck Runs Out... Luck Runs Out... is offline
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Join Date: Jun 2009
Location: Hill AFB, UT
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I have Thorsten rad scoops on my SP1. When I got the bike, the PO had reversed the polarity on the fan, and as long as I did 40 MPH or more, the bike was rock solid at 175-182 degrees. Below that on a hot day, it would begin to overheat, and on one occasion, it hit 252 and the flashy light came on (don't worry- I shut it down immediately and didn't start it back up 'till it was at 190).

I jumpered the fan to stay on all the time in reverse polarity and held my hand over the outside of the right rad to feel if air was going in or going out... felt like it was coming out just a little, and the inlet of the scoop was the same way... then I jumpered the fan to run the correct way, and could feel a strong pull from the outside of the radiator and a lot of wind coming out of the rad scoop.

I figured I'd try the bike like this with the idea that at low speeds, the fan running the correct way would pull cool air through the radiator and overpower any ram air effect, but at high speeds, the ram air would overpower the fan, dropping the temp and causing the fan to turn off, improving airflow through the radiator.

It didn't quite work out like that. In conditions that would cause the bike to overheat, I was seeing 230ish, but once I hit the highway, it took about 15 miles to drop it down to 195, but wouldn't go any lower.

Sooooooo... When I return from my current deployment, I'll be ordering this here fan and be done with it: SPAL USA
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