1979 KZ650 B-3, recently purchased from a local used motorcycle shop. Approx. 700ft. above sea-level. 23,000 original miles. Generally, good running bike/good working condition. No known mods to the engine. Stock Mikuni carbs, I believe. No airbox. MOROSO individual clamp-on silver air filters, good condition (visual inspection). Stock Kawasaki exhaust (4 into 2). Once I've warmed up the bike (at least 20-30 minutes) & ridden at highway speeds for minimum 30 minutes, I see fuel pouring out of #4 carb (far right-side), from the bowl overflow tube (comes out of the bottom of the float bowl, I believe). I don't know if this happens while I'm on the road. It seems to happen only once I've stopped the motorcycle. It will spit out approx. 4-6 tablespoons of fuel, two-to-three times, then stop. I see two fairly large angled screws at the bottom of each float bowl (standard/flat-head slots). No other spills/leaks visible from any of the other carbs. Any thoughts/ideas/suggestions? I posses only a general, rudimentary working knowledge of motorcycle engine mechanics. Carbs have always intimidated me. I do not know if the carbs were re-tuned/re-jetted due to the removal of the stock airbox. Bike seems to run fine at higher rpm's (above 5K), & idles fairly smoothly at approx. 1,200 rpm's (once warmed up). Runs a little rough between idle & 4K rpm's. Do the stock Mikuni carbs have an accelerator pump that can be adjusted? Any help would be greatly appreciated. Thanks!