What happens if?

[Wafer_Thin_Ham]

If you were to overfill your coolant what would the bike do? Just push it out of the overflow I assume, but just wondered.

Like if you overfill the oil a bit usually it gets chucked out of the crankcase breather hose and into the airbox.....
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[finpos]

Exactly that, except of course the expansion system is designed to handle the coolant fluid level changing all the time as it heats up and cools down.

f.

[Wafer_Thin_Ham]

So when it heats up it all the excess just gets chucked out of the overflow. Nice.
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[finpos]

kind of... It's actually supposed to expand into the air space at the top of the expansion bottle. Once it's used that space up, then it gets chucked out. Which happily makes more air space in the expansion bottle, so it may not happen again.

If it does keep happening, your engine is buggered

So, that would fall under the heading of "no real harm done". But, as a good friend of mine will tell you, the breather/overflow is, in fact, in the real world, only meant to be a breather. That's why they are usually cunningly situated to spit slippery coolant all over your back wheel...


f.