figster

i need help, any ideas are welcome. i was recently given a pair of mikuni flat slides 34, but they need to be rebuilt because they leak gas. they told my it was probably the needle jet, but the problem is that i can't find any web site that sells the rebuilt kit and if the do the ask you for model number or part number, which i don't have. all i got is that they where on a banshee and they are mikuni 34 flat slides, also on the side of the carb it is marked like this 34 12 A HD 34 any clues on what model these carbs are?

i did that already and it is still leaking

i need help fast, i replaced the stock pipes on my banshee an also the jetts and needles. i left the stock pilot jet , replaced the the main with 280 and the needles with dno 304, it runs and starts pretty good but it wouldn't stop leaking gas from my left carb. what can be wrong ? need help