decided to take the bike to a garage for them to give me there "expert" oppionion of what the trouble is....
they have told me my carbs need stripping/cleaning/rebuilding/balancing etc
the also told me that the knocking noise is not the tappets (as was my first thought) but the cam chain tentioner that is causing the noise. this thery would make sence. so i am gonna deal with the carbs over the weekend and then look into getting a new tentioner......
thanks for all ya help peoples