weird stuff going on

[Battousai]

i have an 88 600 thatwhen i first bought it it was running great, its got about 42,000 miles on it. then it started missing and fouling number 3 plug out, so i took the carbs and got them cleaned a few times, and still the samething i decided to drop the bike off at the bike shop to get it done right, he adjusted the carbs and said that it was better but still had a bog in it, so he went to sync it and number 3 wast even moving the fluid, not even a flicker. so he pulled the plug and did a compression check on it and it was only like 105 or so. then he check numer 2 and it was 120 so i decided to bring it home to pull the valve cover and check valves and all pulled vc today and everything looks and checks out fine, did a leak down on number 3 with the engine stone cold and it was only 10 % leaking or so and with that many miles i figure thats about normal. so i checked 2 and it was about 15%. did a compression check on both of them and they were 125. i havent put it back together yet, im just trying to figure out whats going on here, when i rode it home it was flooding number three and bogging when i try to run it alil harder. any idea would be greatly appreciated sorry its soo long

[Kfreak]

Is this a bone stock motor? Did you check your float heights before closing up the carb's? If it's flooding, float is set too high or you have a bad float needle. Or even a bad float.

[Battousai]

its got new needles and its got a header and pipe vance and hines, the jet needles are stock so it should be running lean but its not. the float heights im asuming where set when the guy had it

[Kfreak]

Your first mistake is never assume. You are right, the bike should be running lean. That is why it bogs. Probably between 3000 and 4000 rpm's. Re-check the float heights. Did you do the compression test on a hot motor?

[Battousai]

the motor was cold, does it need to be hot? it should be lean but everytime someone is behind me or i pull the plugs it shows rich, either black smoke or number 3 plug is black the others look perfect

[DumbLuck]

check for spark at the #3 plug. could be a bad wire or cap. common mistake : pulling on the wire to remove the cap, resulting in the wire breaking or pulling loose from inside the cap.

The #3 carb could well be boogered up if it truely wasnt pulling any vacuum, but that dont make alot of sense unless there was a massive vacuum leak at the boot or carb itself. even a crappy cylinder will pull SOME vacuum. (105psi aint crappy, maybe not great, but definately not crappy) i'm assuming a valve didnt drop in or toast as there wouldnt be compression.

If you have spark with the plug out, reclean #3 carb and reset the float. If it's way off, check all the others as the seposid mechanic's work would be suspect. make sure everything is all snugged and sealed up when ya reinstall the rail. quite frankly, i have a hard time believing #3 was showing NO vacuum when properly connected to the sync tool.

oh, a final thought. If it proves to be a no spark issue, smell your oil and check it for gas. some unburnt gas may have washed down the cylinder walls and poluted your oil. if so, change it quick, including the filter. If you drain it and get way more than 5 quarts, drain the oil cooler too as it's prolly pretty poluted too.

[Kfreak]

Compression test is done on a hot motor.

Valve adjustment is done on a cold motor.

Did you do a spit test on the header to see if all cylinders are firing at an idle? Or use a spray bottle of water to check evaporation on all pipes?