carb issuers

[andrewrides1]

i have a 50cc bbk perfed out, and im having some carb issues. Back firing and when i hit the throttle it bogs down and dies out. any advice.

[scootnwinn]

When does it back fire? Is the carb/intake all stock? What size bbk? Exhaust type? What Have you already tried? I can guess randomly if you prefer it. ;) <- (that was gentle sarcasm)

[andrewrides1]

after market exuast. i tried adjusting the carb but no cigar. it only backfired a couple times today when coming home from school. but it never has befor. bbk size 72cc. checked vacuum lines everything seems good. the only thing i can think of is the jet i only have an 86. maybe too small.

[scootnwinn]

Have you checked to see what color your plug is? Does it backfire when you close the throttle or open it? Did you move the needle when you "adjust the carb"? If not, if you think it's too lean or plug says it is try lifting the needle (move the clip down a notch) see if it improves. How many notches are on your needle? try adjusting it on the needle until you notice a change for the better. You may need to rejet but tuning with the needle will give you a better indication as to which way you should go. Do a plug chop and post the results for the best advice.

[teddy554]

do you have a performance cdi that will cause backfiring also, your jet should be fine but to rule that out you can go up the next size

[millsc]

my exhaust will pop sometimes, does it pop or actually backfire, all the cheaper exhaust i've put on pop every so often because they are cheap and leak from the rivets.

[andrewrides1]

wont start now any ideas. moved the needle up had to make a groove because it didnt have one. more of a pop millsc. good to hear from you on this new site you always give good advice.

[scootnwinn]

Bummer check the plug is it wet after a period of cranking? Check spark, fuel, and pray its one of those. When was the last valve check??

[andrewrides1]

i adjusted the valves about a month ago. ill be back in a minute

[andrewrides1]

ok im getting a spark how do i check for fuel.

[scootnwinn]

there are at least 2 ways. There is a screw on the bottom of the float bowl generally, unscrew it and see if fuel leaks out (sometimes there is a hose attached under there and the fuel will leak out the hose) Also pull the fuel inlet line it should have fuel depending on where your tank is located it will flow freely or trickle. If your tank is floor mounted check to make sure the pump works by cranking it while the line is disconnected it should squirt fuel. Some gravity feed tanks have a vacuum pet cock that works similarly.

You can also try artificially introducing fuel into the carb mouth to see if fires and runs for a moment. If it does it definitely has a fuel issue...

[millsc]

unplug the fuel hose that goes to carb, then unplug the hose on the manifold suck on the hose you unhooked from the manifold gas should come out the fuel hose that you unhooked from the carb, if it doesn't the petcock is bad or clogged

[millsc]

mine pops sometimes, my plug looks good and my scoot runs great so i ignore it.

[andrewrides1]

ok well i unplugge the hose on the petchcockfrom the fuel filter and after the gas spilled out plugged it back together and its running fine so in guessing this is some sort of fuel problem. why would that fix it. any ideas?

[millsc]

read my post on how to check for fuel and do that your petcock most likely was clogged sucking on the hose unclogs it most of the time

[scootnwinn]

Did you pray Like I told you? ;)

[andrewrides1]

its pulling the same s***t when i try to ride it so im guessing bad petcock. what do you think? is there any way to check inside the petcock? and i also noticed a lot of acid on my battery could that be a contributing facto/

[millsc]

did you check the flow by sucking on the hose from the manifold

[andrewrides1]

ya its fine i just checked.

[millsc]

Is it cold where you live? Try letting it warm up five minutes then try it.

[andrewrides1]

ok it was running bad becaese the air fuel screw fell out luckily it was sitting on the engine. now i got everyhting back together and its working fine for the moment. thanks everyone for the help.

[millsc]

glad it was simple fix