If it is indeed coolant it is not OK or normal. Coolant doesn't just leak out of a bike unless there is a cause for a leak. Like a loose clamp or a bad hose or coolant part. Perhaps the vent hole in the water pump of someplace for coolant to escape from. I have 6 water cooled bikes in my garage most of the time. A few get ridden frequently including the Rocket and including the winter months. One bike sits most of the time time but not one bike leaks coolant. Mityvac makes an inexpensive (@ $30.00) cooling system pressure tester. It is pretty versatile, if you have multiple vehicles and you work on your own cars, trucks, bikes, ATVs, and so on it is worth the money.