There I was having sorted out my clutch problems and thought I would take the bike for a quick run prior to a show. 6 miles into the run turned a corner and the engine sounded different and ground to a halt. Anyway after stripping the carb etc. it still wouldn't start and then it occurred to me that it was blowing through the head gasket (im still new to all this)and there was no pressure at all on the kickstart. Anyway, can any of you please tell me the best place to buy a new gasket? (or two!!)Also what is likely to be the reason for this or is it just common? I have seen in the manual about the sequence etc for tightening the bolts but is there a specific torque that should be applied?
On another note I filled the fuel tank right up for the first time even, normally it I quite low but I was going to a show etc. The fuel seems to be poring through the carburettor. Should it do this??
Your second questions hasn't been answered yet. No it shouldn't be poring out of the carburettor. The most likely cause is the float needle. If this is not bedded in correctly or worn it won't close up the petrol flow to the carburettor as it should. You should take it out and inspect it to see if there is a clear ridge on the tapered part. If there is, it is better to replace it but as a stop gap you could use a little valve grinding paste and lap it in. If it is touching over wider section then it will close the petrol flow again and your leaking problem should be over. if it doesn't then the float level is probably wrong because of wrong thickness fibre washer under the mixing chamber or a wrong bottom nut on the mixing chamber. This is however more unlikely to be the cause.
I also suggest you try first just tapping the float bowl of the carb to see if that halts the flow, and if it does not, just unscrew it, take out the float and needle, then just re-assemble. I have often found this is a quick cure and assuming that you did not have any trouble with this before, it is unlikely that any remedies suggested by Leon are necessary. If you DID have trouble before, then what Leon suggests is probably what you need to do, but first thing to check is if it's simply a bit of dirt or emulsion gumming up things.
As I've mentioned a million times before. If you over tickle these carby bowls they will keep leaking until the fuel level drops to the correct level giving the impression the cutoff needle isn't working.