The water pump cover has an O ring that seals it to the housing so it can be re-fitted without the need to replace gaskets etc. Just a smear of water proof grease on the O ring is all that is needed. You will loose a small amount of coolant so remember to top up your coolant. Fill the radiator so that the coolant is level with the bottom of the filler neck where it connects with the top of the radiator. The filler tube needs to be empty to allow for heat expansion. A handy tip for easy fitting of the radiator cap is to shorten the overflow tube so that it is only as long as the diameter of the radiator cap. See photos.
Another handy tip is if you have kids on bikes, connect a hose to the overflow and direct the hose so that it drains on to the exhaust pipe. The idea of this is that if the bike over heats the coolant will drop on the exhaust creating heaps of steam and the kids will notice it, you hope!! It might even be handy for yourself.
Recommended Coolant:
The Beta manual specifies Bardahl Permanent. Beta Australia recommends the use of Motul Factory Line Coolant. Team Beta WA uses Belray No Tox Coolant. Silkolene also produces a coolant recommended for magnesium housings.
Coolant Changes:
The Beta manual specifies changes every 120 hours of operation.