Leaking Coolant

[Bry]

My bike is leaking coolant from the overflow tube on the expansion tank. It is fine on short trips but anything over 10 or 12 miles it happens. I have flushed out the rad and put fresh coolant in but it still happens, anyone got a clue why this is ?

[masterofinsanity]

could be a blockage in the coolant system? any signs of the dreaded head gasket?

[Bry]

No not realy, there is no gunk in the oil and the bike doesn't get too hot

[Northern ANdy]

is the expansion tank over full?

[Bry]

Not above the top line. I have just looked at the rad cap and there is a small split in the large seal, would that cause this prob?

[Northern ANdy]

certainly won't help. Swap that cap and see how it goes.

[zimm]

sorry to be the bringer of bad news .. and of course i may be wrong .. but if its blowing water out of the expansion tank on runs longer than 10-15 min and NOT overheating/running hot.. its quite possibly blown the head-gasket and is pressurising the cooling system.

[Bry]

Yep, gave in and put in a garage and it was indeed the head gasket. never mind done now