toffeecrisp

thank you so much for your help

how long will the head gasket last roughly??

hi all i brought this bike and this is the problem the person who had it the thread got knackered on the head then it decided to crack, replaced it with a standard 125 head and piston, now when i try to start it, it will try and try then backfire with a little white smoke and try some more but wont start.aparently it was working fine before even though the head was the spark is sparking petrol flowing and 2 stroke lubricating, i cant see why it wont start as all thats been don is had is had replace the broken head and pistons so its a tzr 1995 model and i need this for work the peron said to me it's the main jet which is a 260 and needs to be a 210 it beem bored to 65.5mm i now have standard head which is 56mm bore and piston please help many thanks.