kfx 400 problems

[busafantic]

Today my uncle was riding my kfx 400 and came back and said something is wrong with it. Like when u give it a hole lot of gas it starts to bog. help me please ASAP!

[kfx400rider03]

is the air filter realy dirty???
if not check the spark plug.
make sure all the air tubes connecting to the carb to the air box are on good

[drzoo2]

Plugged main jet?

[busafantic]

I checked the air tubes they seem to be fine and air filter. Is it the spark plug? because when i fire it up it idles fine .

Reply ASAP

[jonboy]

Try tapping on your float bowl with the handle of a screw driver. If your float needle is sticking it could cause it to do this. I've had this same problem before. Also check your plug for a weak spark if it fires with a thin yellowish white spark then change it. It should be about as thick as a dime and brite blue.

[kawi_rider_97]

It sounds like your CDI might have a bad connection or it might be bad.

[QuadRid3r442]

there could be the smallest tear in the boot that goes from the carb to the engine. That happend to me once and when i got a new one everything ran fine again.

[tferguson28]

so have you took it in yet or figured it out because it sounds just like the problem i'm having right now too. when you get it figured out be sure to post.

[busafantic]

CHECK YOUR MAIN JET IT MAYBE PLUGGED.

[ifixtheyride]

Hate to give you yet another angle but does it do it in all gears? You said idle is good so go down the road and try more then one gear. There is a stupid switch behind the gear shifter that when it gets bad connection it makes the CDI run like the rev limiter is on. The switch is located behind the shifter and mounted with I believe 2 socket head cap screws. The back of the switch is like white potting. Remove it then take scotch brite or fine paper and clean contacts. It has like 5 pads on it for every gear I chased this one for an entire weekend one time after removing the carb about 100 times!It ran like a raped ape after that.

[tferguson28]

do you mean infront of the shift lever? and yah it does this in every gear