Water in front Cylinder
 

My St4 went onto 1 cylinder after I hit a brick. The only visible damage is the front exhaust is dented.
However the bike runs fine until the cooling system cuts in, then it just goes onto 1 cylinder. I took out the plug and turned over the bike and water was spat out of the front.
Any advise would be appreciated as I've got to fix this myself.

When you say it starts to run on one cylinder when the cooling system cuts in, do you mean the fan starts or it just begins to get up to temperature?
If water is getting into the front cylinder it can do so only really from two places.
Head gasket or a cracked water jacket.
If the brick hit the exhaust hard enough to dent it, maybe it carried enough energy through the studs to damage the cylinder????
You really won't know until the front cylinder is off.

Hi Nelly,

It runs on one cylinder when it gets to normal temp.
I've just bought a Haynes manual so I can get on with removing the cylinder and can have a look. Fingers crossed its just head gasket but more likely its the cylinder itself. I recon the brick hit hard as it breifly lifted me and the bike up.
Thanks

Must have been some brick!!
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