I have a 2001 KX 125 and I've got four lines running down from the carb. Where do they go?

Check your fuel filter, sounds like it maybe clogged or needs replaced, can use a generic gas filter to fix or troubleshoot your problem. Rick

Well - not knowing the condition of the bike it could be a lot of things. I would start with a fresh spark plug, fresh fuel and a clean air filter. You say you already did the carb, reeds and top end - good. I assume you set the float level correctly. Did you pull out the petc0ck from the fuel tank - theres a filter that might be plugged up. Check your exhaust system for plugs - I've seen mice nest in pipes over the winter. If all this fails, look into your power valve system to ensure it's working and adjusted properly. If so, then do a leak down test - you might have a lower end leak. That's the best I can do without seeing or hearing it run. Hope this helped!

Sounds like there could be a problem with the main jet not delivering sufficient fuel for normal running. Clean out the carb and check the jets and passages for obstructions and dirt.

i had the same issue. it's gonna be a blockage in one of the vent tubes to the carb. check the line to the left of the carb that runs next to the gas tank. if thats fine then check the gas cap line. then if thats all good then check the line that runs below the carb. these are all vent tubes and allow the carb. to refill with fuel

sounds like you need to rejet the carb..

Hello you have a
1. fuel starvation problem clogged carburetor jets.(clean the carb)
2. Intake leak carb joint/intake manifold.( start your motor get it to idle best you can spray wd40 around the carb joint if the rpms change you have a leak replace the carb joint or gasket/o-ring as needed.
3. crankshaft main seal magneto side leaking or worn main bearing.
check end play on the magneto side remove the cover plate firmly grab the end of the shaft with up an down motion if you can feel it move replace the main bearings and seals.
These are problem that will cause your motor to run lean and hesitate.
Hope this helps you with your problem

jetting in carb

The float needle is stuck open and not shutting off the gas. Lightly tap on the bowl with a screwdriver handle and it may stop. If it doesn't then remove bowl and clean the float needle and seat.

Hi
I have been working on my carb today,the pipe from the bottom of the carb should just run down by the bottom of the swinging arm,there should be another pipe from the pipe on the left side of the carb just above the fuel intake which also runs down to the swinging arm and connect to nothing.
Cheers

sounds like the needle and seat may be the problem