Stupid noob question

Hello. I'm a newb to motorcycling and also motorcycle repairs. I'm an Engineer by trade so not a complete novice. I've just bought 2000 SV curvy as a winter project and am in the process of removing the fairing to change the front end. I have removed all the fairing mount brackets from the frame but there is one on the right hand side at the front which also supports a plastic bottle. The expansion pipe from the radiator goes into it aswell as an open tube from under the airbox. Is this bottle just to stop the radiator pumping scalding hot coolant onto your leg or does it serve another purpose. Basically I'm asking if I can ditch it or does it actually have a job?
Ta muchly

[tj2]

It is an expansion tank.......

[Flybuster]

As the coolant heats up, it expands. The bottle is there to take up the the extra fluid. The level drops again as it cools. As it heats there is also a fair amount of pressure built up so never take the top off whilst the coolant is hot. It'll throw out boiling hot liquid.

[yorkie_chris]

There's no pressure in the expansion tank flybuster, it's at ambient pressure.

There is a wee bit of pressure inside the rad but normal op temp is in 80 degree region so not like it's going to steam clean your head off at the waist.


The expansion tank is kinda necessary. But not necessarily that tank, I just put a little ally water bottle cable tied to the right hand side of the radiator. (I've got an air horn where the tank would normally go)

Cool thanks guys. I need to trim down the mount bracket as it also holds the fairing and they're not going back on.

[Mickle]

The only stupid question is the one that does not get asked

[Flybuster]

Originally Posted by yorkie_chris

There's no pressure in the expansion tank flybuster, it's at ambient pressure.

There is a wee bit of pressure inside the rad but normal op temp is in 80 degree region so not like it's going to steam clean your head off at the waist.


The expansion tank is kinda necessary. But not necessarily that tank, I just put a little ally water bottle cable tied to the right hand side of the radiator. (I've got an air horn where the tank would normally go)

Cheers YC, you are of course right about the expansion bottle but I thought there'd be pressure built up behind the radiator cap.
I know there is with a car cooling system but never had any dealings with a bikes and presumed it would be under similar pressure.
That is why I joined the forum mind....to learn.

[yorkie_chris]

There is pressure behind the radiator cap just not masses of it, couple of pound