Bonneville America Forums Forums Technical Forums Performance Mods Needle advice with NARK needed (2002 Bonneville)

Hi guys
So I removed the airbox, and now I'm not sure about needles, and I don't have access to a dyno. Previously, I was running Bub Exhaust, 125 mains, thruxton needles with two shims, 40 pilots, Unifilter.
Then I removed the airbox, put in 140 mains, which seem, judging from others postings and Pats calculator to be on the small side. However a plug chop after 50 miles at 55-65 mph showed sooty plugs even tho I had removed the shims on the thruxton needles. Should I buy stock needles, or go back to the Dynojet needles that were on the bike when I bought it, and go up a notch on the clip??
Seems like I should be running a 150 main jet, so at midrange things will only get worse with the thruxtons
STu

Try the stock needles first.

and possibly shims

Frank

You didn't mention your exhaust, so I'll assume its aftermarket. I'm running 135 mains/45 primaries/3.5turns out/thruxton needels/1 shim/ pods. Air box halved and America exhaust with all the baffels removed/ diffusers still in. I went down from 145, which I thought were rich, but did not have the idle screws at that time. I'm going to try Pats suggestion with 150's and my current set up. I'm also going to spring for the dyno and the sniffer test at the local go-fast shop. I'll repost after the changes.