AW 400 Mik jetting spec

[Jumbo J]

guys what jetting is good for 38mm mikuni on the AW400
main, pilot, needle, needle jet, air screw,  slide cutaway, - anything i missed?

[g465b]

hi,    slide  2.5     needle  6DH3    nj    Q-0 #166 series     main   330     pilot 55    clip  mid/as required       approx   120 m above sea level

        air screw  1 1/2  to 2                    from back in the day when we had real super leaded fuel.         cheers G

[Jumbo J]

Thanks G - very helpful cheers. gearing 14T fr - Rear  ?? (currently it has a 57T) - haven't run it yet tho, most our tracks in NSW don't have long straights

[g465b]

hi j j,  standard gearing was 13/56    g.

[Nebo]

   
        Re Mikuni Jetting. g465b  has given a  good starting point. But some Mikunis have a small Air Correction Jet in the small hole in the Carb inlet.

        If this hole has a thread in it the jet should be a 0.5.  This Jet effects Starting and 1/4 Throttle.   If there is no thread do not worry about it.

         
Be very aware that it may have bad Detonation and Pinging in the mid to 3/4 throttle  range.                     With todays Fuel you may have to run a ritcher Needle and or Needle Jet.   

  Do some testing before running the engine at race pace.   Or Engine damage will result.              Even Maico 1.01 states this when running a BING carburetor.