I have a 1988 zx400g which is the import grey version, it has the same frame and engine as the h1 uk version.
The story so far..... i start the bike which seems all good no struggling or ignition problems which is great, She'll run ok and warm up after 10mins or so which is good. gauge reads just on the first mark on the gauge. All seems not to bad. but i ride for 3-4 miles doing no more than 50mph and under 7,000 rpms so not stressing the engine at all and the gauge needle creeps further and further in to the middle. After 10 miles she is almost on the red and i have to stop. coolant boils out of the expansion over flow. but only when i stop and turn off the bike. when i take of the tank plate and airfilter box steam is coming out of the gearbox breather hose into the collector box. And in a a polite way stink's bad!!
I have flushed the rad and engine itself with a mains hose, i have replaced and checked the thermostat, the water pump turns and the fin's are ok, i have also have tried a coolant leak fixing agrent in with the coolant. no different.
This is a real heart ache for me as this is my first big bike and it passed a mot only a few weeks ago and is tax for a year.
I live in devon and have tried searching online on ebay for a gasket set for my engine but with out luck... just incase it is the hg gone but i was told by a family friend it could be a cracked head!!!
I even thought sell it and had it on ebay for only £500 which i thought was a bargin for a bike with 12mths mot and tax.... but no one bought her!!!
![Sad :(](./images/smilies/icon_sad.gif)