2003 kawasaki KX 250 - Page 3 - Answered Questions & Fixed issues

sounds like it's flooding...majority of pipes "don't" require jetting in older 250's...if they sent the jets with the pipe, find a happy medium in the numbers...for instance; if you had a 118 stock, and they said use 124, use a 120 instead...bottom line, you gotta reduce the fuel...quick trick ? just loosen the clamps on the carb and turn it sideways and remove the bowl...you don't have to remove the carb to re-jet...

you would need to change the main and the dust seal.
Pump out the piston then remove the dust and the main seals then clean out any white powder residue in the slots where the seals were, clean the piston with wet and dry paper or 1000 - 1200 grade glass paper and replace seals lubing up with brake fluid first do not use oil or grease as this will swell the seals and replace the piston, you may need to give this some GENTLE persuasion with a G glamp.
It's easier when bleeding your system to leave the caliper loose and also any ties that hold the brake line to the bike and try and get the caliper held above the fluid resevoir thus making it easier to expel the air as you have quite long brake lines in this bike.

Hope this helps

this is probably a specialist job, with some special tools and high pressure nitrogen for regassing

Look for where the tube from the radiator goes to the pump on side of the engine there should be 1 screw which has a fibre or copper washer,undo this.
Hold a suitable container covering the hole then take off the radiator pressure cap & watch it gush out!!
Flush with water ( put a hose to the pressure cap & rinse)
Replace bolt & fill rad & expansion tank with fresh coolant, run for 5 - 10 minutes then top up the expansion tank to max
expansion tank

Hope this helps (if so please mark as helpful !!)
Ride safe
Bike-Doc

Best would be to re-ring the piston you have unless it is damaged. To check the cylinder for wear, remove the ring from the piston and use a feeler gage keep using a smaller one till one fits, if less than .005 ok to re-ring. if more than that you might see if you can find a larger piston. one that fits at .0015 -- .0025 is good fit.

if it is piston slap,you will need pull the top off again and measure with a feeler gauge between the piston skirt and the sleeve, should only be a couple of thou

The exhuast valve set-up on a performance 2-stroke operates only at higher RPM.

650-700ml

cable is bound up and carb slide is sticking. Remove and clean

if you tried the clutch dry it will grab. if you tried it with the oil in it and it grabbed, then adjust the cable. about 3 mil gap on the lever.

There are three positions. Usually when the handle points to the rear of the bike the fuel is off. When the handle points down the fuel is on and will feed fuel until the reserve level is reached at which time the bike will stop running. When the lever is pointing toward the front of the bike it is on reserve and it will start and run until the bike is completely out of fuel. If you run on reserve to get to a source of fuel remember to put the lever straight down or next time you will not have a reserve. When the bike is parked the lever should always be in the off position.

SILKOLENE PRO RSF 5WT or use
SILKOLENE FORK OIL LIGHT
500-MLS OIL EACH LEG

shop time would be around 3 hours @ roughly $58.00 per hour depending on where you live. Split cases remove and replace gear (if that is cause) plus shop materials would cost you in the $ 245.00 plus or minus range. If you have a good mechanic/honest it can be done for less or more depending on if it is indeed just the gear. Remember ! this is for current charges in my area. I have heard of shop rates pushing $70.00 per hr

then do it very cearfully,,, all you need to do it take off the float bowl to clean out the running jets,, but dont go poking whire into them as you will bistroy them,,,
to be honest it sounds like its running a bit rich,, too much fule going into the engine,, makes the plugs go black and sooty

THREE TEST CYCLES IS REQUIRED TO CONFIRM READING WITH THROTTLE HELD WIPDE OPEN

If the clutch lever is properly adjusted, this is normally what happens if the gearbox oil is extremely dirty. Do and oil change then ride for 30 minutes. Then change the oil again to help flush out the dirt. If that doesn't help, then the clutch pressure plates are warped or the cork on the fiber friction plates is swollen from using synthetic lubricants in the gearbox. Check the plates and replace as needed.

The plug on the side engine casing is for 10w40 motor oil. NEVER use synthetic lubricants or oil with 'special' additives. They can mess up your clutch. The 10w40 motor oil is shared by the gearbox and the engine because they are a single unit.

Use 4 ounces of two stroke engine oil for every gallon of gas. That will give you a 32 to 1 mixture which is the industry standard. If the outboard motor is a 2 stroke (most of them are), the engine oil is the same. Note the difference > Engine oil verses Motor oil. Motor oil in the gearbox, Engine oil in the gas.

From Kawasaki or Ebay etc

Good Luck
Hope this helps.
(If it does then please mark this as 'useful')
Ride Safe
Bike-Doc

does it run out of fuel ? remove the screw on the carb bowl and fuel should run out if not the is blockege somewhere from the tank to carb trace back , is the a spark ? maybe your coil / ignition are bieng effected by the heat from the engine ?,you need to check these things and go from there.

Hi and welcome to FixYa,

For the wiring diagram of a 2003 Kawasaki KX250, have you tried here?

Good luck and thank you for asking FixYa.