I think the problem is that most people leave it (or any cleaning agent) to "soak" for too long before rinsing off. Castrol recommend 1 - 3 minutes only, then thorough rinse. I can only say I've used Greentec for years and all my bikes stay looking like new (and I'm a bit anal about them and my cars). Maybe it's the Motorex stuff that's doing the job?
