There isnt a best setup, every bike and combination is a little different and needs different adjustments. Engine condition, quality of tune up, exhaust design, intake restriction amount, elevation, temperature, humidity, how you ride, etc all affect the jetting that will be needed. That said start with 1 main size larger. Check compression and verify engine is healthy, do basic tuneup....valve adjust, timing chain adjust, point and timing adjust, verify timing advancer works correct, new plugs and correct gap. Verify you needle jet position is in the stock middle slot. Verify and adjust float level and do a running sync on the carbs. Then with you 1 size larger main jet go for a ride and see how it runs and note any flat spots or boggs etc. Run wot with a good load, start slowy closing the choke....if the engine picks up then you are still lean.....if it bogs down then it is too rich. Do the same thing with the choke at half throttle or any time you have a surging or a bog and figure if you are rich or lean. Start with wot and the main jet, the work out the mid range with the needle jet position.