raising coolant in overflow

i just finsihed building my quad and i fill the coolant up in the radiatior and then fileld the over flow bottle to the full spot. for some reason now it is way over the full line on the bottle. what could have caused this? what shouyld i do?

drain out some fronm the overflow by taking the line off where it goes to the radiator....I'm not sure what caused this but somebody else will know

Overflow should be filled to bottom line cold and the radiator full.
After running the engine, it will push some coolant back into the overflow allowing some room for air and expansion at the top of the radiator. It should then settle out between the low and high lines.