Since I bought the bike, I've had trouble with a popping noise from the exhaust on deceleration and a 'sneezing' noise from the carb.  Lunchbox filter, aftermarket slip on, 40 pilots, 50 mains, 2 shims, 3 turns.  Before today it had 3 shims and ? turns.  When I started it up I noticed that fuel was blowing out from the carbs.  Any idea why this would be happening?  Obviously, it still runs like garbage.

Umm, is "50 mains" a typo?  If not, there's your problem.  You are running lean regardless, even if it isn't a typo.

Depending on your slipon, you probably need 150 mains.

Have you synchronized your carbs or checked your valve clearances?

Sorry, yes, 150 mains.  I did valve shims about 500 miles ago and synced the carbs this morning. 

When I pulled the carbs off the bike just now, I noticed fuel pooled in the carb boots.  That can't be good, right?

Quote from: snOhio on November 09, 2013, 02:55:20 PM
Sorry, yes, 150 mains.  I did valve shims about 500 miles ago and synced the carbs this morning. 

When I pulled the carbs off the bike just now, I noticed fuel pooled in the carb boots.  That can't be good, right?

Ok, did you check your carb floats for proper height?  I knew I forgot something.  If the floats are set too high they could flood the carbs.

Have you recently checked float level or if the float valves are sealing well?

+1 to Ron888 & Tialloy ...
But - your bike is an 89-00 ? If not, your jets are wrong. You need 20/147.5 of the right type.

Cool.
Buddha.

Yep, it's a 93.  Jets in the bike match the wiki.

Any chance your 40 pilot jets are the bleeder type with the extra holes in the shaft part of the jet?

Nope, not bleeder type.

I set float levels and checked them on the bike - gas is right below the gasket line. 

The bike will sometimes start, but when i give it gas it bogs.  I can ease it up a bit, but if i get on it any more the exhaust note changes and sounds like, well, farting.  It eventually dies and doesn't want to restart.  Meanwhile, when trying to start it I'm seeing either vapor or smoke coming back out the right carb.