Was 59F yesterday, 2 deg under the record high temp for this date that was set in the late 1800s. So I also went out and applied ACF-50 to the AK 550. After almost 2 winter seasons of riding in the cold with the road conditions that come with that the exhaust system is still looking really good. I didn't use ACF-50 last year but figured I needed to get it for this year before corrosion started to build up.