The popping is pretty rapid as soon as i let off the gas while slowing down, so i'd like to quiet that out a bit.

Im not sure of my mixtures screws because i was only trying to change one thing at a time. The pilots were 55's, i brought them down to 42's, now im getting popping, so im ready for the next step.

Is it worth my time to just change the mixture screws, and then see what happens? Or is it pretty much obvious that im running lean with only 137.5 mains?

Dinqua:
I had it out WOT yesturday on some pretty flat roads and i cant say that i noticed any difference when i let up. My conflict is that everyones upping the size of the pilots, but you recommend not to.

So whats the solution:...bigger mains smallest pilots, or slightly bigger mains, slightly bigger pilots?