My KDX sucks the gas! HELP

[svtnut]

:whoa: My sons 1998 KDX 220 is only getting 38 miles on the o-meter before he has to go to reserve. We had a Pro Circuit exhaust on for a while, then put the stock back on hoping it help on fuel.... Not much. I've checked the reeds for cracks,clean the carb and air filter and change the plug. The bike doesn't seem it's in desperate need of a rebuild. I read these KDXs should go 80 miles on a tank trail riding or 60 miles riding hard.
Where should look into first?

 

[mideastrider]

That's not much for a kdx. Are you sure the "O-Meter" is accurate? if so what about gearing? Someone may have geared it down. Just something to check.

 

[crhines]

likely leaking gas out the Carb. I had the the same issue a few years back. Check carb float level and float valve needle.

 

[G. Gearloose]

Piggy jetting,
Loosing fuel from carb vent/float high
or both.

 

[SpDyKen]

No, gravity is pulling it.

 

[svtnut]

The odometer seems to be pretty close.... I haven't seen the gas poor out any of the overflow or vents. His buddy rides a CRF 150F and goes several days on a tank. My son rides the same places with him and can't get a half a day. I may take the carb to the local shop before I give up and buy a 4-stroke.

 

[kdxtaz]

when I first got mine used it did the exact same thing. after replacing every single part in the carb, including the choke and o-rings in the jet block, I finally just bought a new air striker carb. problem solved. not much help, I know, but just couldn't figure out what it was. it wasn't leaking either. the only part that's not replacable is the needle jet port so I thought maybe that was worn.

 

[ascracer]

I'd check the float level you will not notice gas pouring out of the carb but as your going down the trail the gas sloshes out. One other thing is check that the brakes are not dragging. I know this sounds dumb but it happens. Take out the brake pins and make sure they are not all rusted to make the brake pads stick. If they are just use a little emery cloth or wire brush and clean them. I apply a light coat of grease to the pins before I reinstall them. It just keeps them from rusting as quick.