Had my UltraCool fan assisted oil cooler hooked up to my 2009 FXDC Super Glide Custom at the beginning of the season. Riding on our first day at 80 degrees and I was very happy to see that green LED indicator light pop on. It stayed on for around 10 minutes, did its job and the light went off. What a great feeling to know this sucker is adding life to my engine and helping maintain viscosity to my oil, and most important my ass will be burning less in August 🙂 Oh the light went on while I was on a back road and I pulled over just to hear it working. 2 Thumbs up. Do yourself a favor, If you have an air cooled engine just get one of these babies.