Cos after rebuilding the entire bike from frame up, was time to hit the key for the Kats first time in over 10 yrs..... Turned fuel tap on, carbies leaked everywhere. Replaced all the needles and gave a good service (as per that guide), but didn't replace the 5c o-rings in the fuel lines between each carb body.... was very disappointing as we couldn't start the bike up and had to wait another week to have time to redo....