300/440/550 Help tuning a BN 44

[Dan Rudd]

I had previously posted this in the 550 area but got no response and very few views. I'm hoping someone in the General area can guide me a bit. Thanks,

My son saved up his money and bought a real nice 86 550. The motor had been previously built up. It has a Ocean Pro head (my previous post I thought it was a Westcoast head but my son corrected me), Coffman half pipe, Westcoast waterbox, Ocean Pro intake, as well as all the handling goodies (plate, grate, etc etc...). The carb is a Mikuni BN44
We just had the top end done w/new pistons/rings and bore job because it was way out of specs.
We put it together and in the water and are now tuning the carb. It's running pretty good but needs tweeking. We're starting with 1 on the H and 1 1/8 on the L and 1 on the Pilot. I'm somewhat comfortable with tuning the H and L but not the least bit familiar with tuning a Pilot jet. We seem to be running rich on the L side, but I'm OK with that for now until the motor has a little more time on it.
My confusion come in to play when I'm trying to tune the pilot jet. Where does that fit into the puzzle? When do I tune that? and for what responses?

Thanks,
Dan
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[shawn_NJ]

Cant help you with 550 specifics. I messed around with one of those 44BNs back 8 years ago on an X2. I could never get it to run anything better then subpar, no matter where any of the screws were. I swapped it with a stock Kehinin carb and it ran perfect. I personally wouldn't put the effort into the BN carb, when stock carbs (mikuni 38's or SBN44's) can be had for very reasonable in the used market, and have hi-tech features like replaceable jets...lol