Good Day Guys

Need help Urgently Have a Honda VFR400 grey import hade it for 1 year & it went in for a service after geting it back the bike was not the same. The air filter they put on melted into my carb & the carb was damadged. I then got a second hand carb & fitted it with no luck the bike has no power so i then read about how to check for valve clearance Major problem did the hole valve clearance from begining to end started the bike & it was 80 % beter then before. Did not ride the bike till the other day & there was a funny Tapping Shuttering sound coming from Cylinder 3 It is a bad sound & i dont know what to look for a what it can be. I dont want to drive her like this & then the Engin blows or something like that If someone can just give me some pointers to check I will appreciate it thank you

Howdo. I would bet 50p that this is the vacuum spigot for the fuel tap needing the hose refitting or if it was blocked, then being blocked again. it is under carb three on the inlet to the motor - the vacuum hose should be on it..