new issue: idles perfectly but on throttle, pops loudly and fires unevenly

[axl_foley]

hey! these forums have helped me do so much work on this bike over the past year or two and i had it running beautifully.

but i recently moved to CA and brought the bike in the back of a moving truck. there was atleast one giant bump i hit where i thought everything in the back of the truck would be upside down. when i arrived in CA, the bike drove fine up to the 5th floor of the parking garage.

now, there is all of a sudden some major issue:

it starts on the first kick and idles perfectly. if i give it a tiny amount of idle, it is ok. but as soon as i roll or snap on the throttle enough to "go," the engine starts popping super loudly and sounds almost out of sync. the left side seems worse. white smoke is coming out of the exhaust. (these are not the pops when you release the throttle because you have a rich mixture)

last year i rejetted the carbs and had them synced. also adjusted the valve gaps and tightened the clutch. ran perfect for the past year or so.

recently, i have taken apart the carbs and re-gapped the valves, which didnt fix the issue.

maybe something got knocked around/loose while in the back of the moving truck? not sure how this issue just started up out of nowhere.

i cant figure it out! heeeelp! could the mixture screw be off? i may have it too rich since i took apart the carbs. i also bench synced it so it may not be perfectly in sync. (but these were things i did after this issue started and nothing changed)

here is a video: https://drive.google.com/file/d/0B4kCNN3VvGJ7SUsxQVRHTzlOX1U/view?usp=sharing

 

[axl_foley]

so two nights ago, i may have fixed it because i was able to ride it last night.

i guess my initial theory was correct: moving from 1000+ foot elevation to 86ft elevation was too much for my little carbs to handle. so i tightened down the fuel/air mixture screws and it worked! when i tried that the first time, guess i turned the screws the wrong way.

im not quite sure how to really dial them in though. do i just keep opening up the screw (one side at a time i assume) until i get the pops when i let off the throttle, then dial it back in until the pops arent really there? i dont want to get to hot by running too lean.

i assume turning the screws out enrichens, and tightening them leans out the mixture?

so i guess having the mixture too rich was bogging down the engine when i rolled on the throttle?

 

[xschris]

A change in elevation will affect a carb bike. Turning the screws in will lean the bike. If the bike is fully stock I would start with the stock settings and jets. There are threads on carb tuning and doing plug chops on the forum and youtube.