kawasaki KX 250 - Answered Questions & Fixed Issues - Page 8

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.

hhhmmm,
Being the front of the motor may make this suggestion a bit silly.... I have heard of this sort of problem before and it turned out to be air sucked through the throttle butterfly plate bushing. Happens only when certain vacuum is present and the throttle plate is in a particular position,revs at a certain point etc. Check for wear in the bushing. They can be re bushed, or get another carby for it. Check also that you dont have any intake manifold leaks. Use carby cleaner about the manifold,quick spray and the revs change means that you have an air leak, could cause a whistle/squeak noise also. Hard to find these sots of things. I could suggest having a fiddle with the throttle shaft when the noise occurs, to see if you can isolate it better.
Seeing that it comes from the front of the motor, check all your exhaust for good seal also. With a bit of back pressure, it may be a leaky exhaust up front. Bit of a worry that it keeps chopping up bearings. What oil mix are you using? I doubt that it is engine internals. Unless something is very wrong. May also be a water pump if my other suggestions wrong. If it relates just to revs, then sounds like a bearing... maybe waterpump. If it stops when you roll the throttle off keeping the same revs, i reckon intake or exhaust leak. Let me know what you find. Cheers
regards robotek

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

hi,most two strokes in the mx range run about 40-1,but me being me i always prefer to run my 2 strokes a little bit oily around 33 or 35 -1,2 stroke oil is very cheap compared to scored barrels or seized big ends...cheers

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.

50 50 mix

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.

Its a nut and bolt job ,you may have a problem getting the calaper to fit back over the disc .If this is the case drain off a little fluid to allow the caliper piston to be pushed back in the caliper housing ,this gives the pad room to fit over the disc..If in doubt speak to your local kwaka dealers mechanic ,for some good advice .

you can use a thing called a nutsert. it works like a rivet. it leaves a steel thread captivated in the hole. i have used these 100s of times.they are brilliant. but you will need a special riveter to put them in.

change the thrust bearing.

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

You have a couple jets in there, one might be clogged up, they are not adj, but your idle should be adjustable, You can take up the slack in the cable for a higher idle, If that doesn't do it, you have to get the slow speed jet going.Sometimes a squirt of carb cleaner will fix it, sometimes you have to take the whole thing apart and soak it in cleaner, then run a wire through every jet. Hope this helps.

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

HAVE YOU TRIED A NEW PLUG FOR STARTER BUD

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.