Bike Overheating! HELP!

[GazW]

If you go to a friendly garage, they can use the probe they use to measure exhaust emissions to check for gasses escaping out the top of the header tank, this will eliminate HGF, if the thermostat isn't opening then you are drastically reducing the efficiency of your cooling system as coolant isn't flowing, find where it's located, pull it out, chuck it in a pan of boiling water and a valve should open. If it doesnt then that's kerput. Start simple, the thermostat removal will drain your cooling system as it will be submerged in it, so buy some antifreeze before hand. If your head gasket has gone you will normally notice other things, check the dipstick/sight glass for a 'Mayo' style build up emulsified oil/coolant mix. Google rover HGF and go on images to get an idea of what it looks like. Good luck!