KDX250 advice

[codyKDX250]

Ive had my 91 KDX250 for about two yrs and have had nothing but trouble. i guess you could say that it started with me putting two much oil in the fuel, but the bike didnt really run good at all from the start. it smoked alot and took a while to even get it started. so i was thinking that if i would do a compleat tare down clean and replace the parts that needed replacing that i am hoping that would fix the problem. dose this sound like a good idea? dose anyone know what this might cost to have a shop do this? any advice would be helpful thanks.

 

[maddawg]

I would do a compression test on the cylinder. I think for your bike it should be within 115ft/lbs to 150ft/lbs anywhere in there your good. What is the ratio of fuel to oil? Try 32:1 that's standard. I wouldn't rebuild everything just get to the souce of the problem and start with those things.

 

[JasonWho]

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[codyKDX250]

ok i wasnt to clear in my post. sorry. this is what i have done to try to fix the problem. first i drained the oily gas from the tank. tryed to start the bike without the plug a few times. took the carb apart and clean with air and carb cleaner.changed the plug a few times, cleand the reed vavles and still no change. it would still be real hard to start and would smoke a lot. how i am mixing the gas now is i take a five gallon can and put 3/4s of a pint in to mix. not sure what that ratio is. i do own a service manual but no owners book. im just thinking my next step would be to disasemble the engine to clean and replace parts. it must still be full of oil. im also thinking of buying a new carb. im willing to spend a few hundred to fix but with in reason. i just want a bike i can get on and start right up and ride. the KDX250 is a good bike i would rather put a little money into it then try an find a good bike for under a thousand. i only payed 800 for this bike.........thanks for the replys

 

[JasonWho]

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[dirt bike dave]

The KDX 250 came with horribly rich jetting stock, and at high altitude will run even more rich. If you use the search function for old posts my Matt90GT or some by myself, you can find lots of good info on how to set up a KDX250.

Basically, Kawasaki did a horrible job with the jetting and forks, but with some tuning it is a decent bike (though heavy for a 250 2stroke). After dialing the bike in, I enjoyed it more than my KDX200's.

 

[Rhodester]

If a compression test comes out ok I would drop the pilot jet and main jet 2 sizes each and see how it starts/runs. That's asuming that you've already tried setting your air screw at 1 1/2 out as a base line and leaned it out from there (more turns out). The air screw can make a big difference in how it starts and runs on the bottom end. If it's still too rich at 2 turns out go with the next leaner pilot and continue from there.

 

[codyKDX250]

oily as in i put a quart of 2 stroke oil into a 5 gall can. i miss understood my buddy when he said put a bottle in.

i will try what you guys are suggesting. do you think the startor might be a problem to and or those disk easy to fix. i noticed that there pretty pricy.
thank you for the advice

 

[cicone]

oily as in i put a quart of 2 stroke oil into a 5 gall can. i miss understood my buddy when he said put a bottle in.

i will try what you guys are suggesting. do you think the startor might be a problem to and or those disk easy to fix. i noticed that there pretty pricy.
thank you for the advice

20:1---that's good for my weedwacker and '58 Evinrude!!

 

[JasonWho]

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[codyKDX250]

hey guys just did a compression test came out to 75. so i took the top end off found alot of carbon. the pistion rings were very lose not sure if they are supposed to be ill find out when i take it down to get it sized. i sure hope that after doing all this it will work. ill update later. thanks again for your help.

 

[JasonWho]

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[codyKDX250]

well when i got the bike about 3 yrs ago.( which i only rod it three times with in that time). the bike sat in a garage with the swing arm off for about a yr before that. the guy that had it before me pretty much ran it into the ground. i dont think he did to much maintanance to it.

i wound up taking the top cap off found that the piston was burnt and carbonated. then i took the cylinder off and it needs a good cleaning to. as soon as i figure out how to get the piston off of the rod im going to take the piston and cylinder to a shop and get it miced and cleaned. looks like it will be awhile before i can get a piston kit but i will keep you posted. thanks again for the help

 

[JasonWho]

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[codyKDX250]

i had my uncle show me the c-clips. i do remember seeing in the forum about them and to discard them now i know what there talking about. ill get some pics up to show you what everything looks like. theres a shop around here that may not charge to mic everything. but ill find out price. (those guys are pretty cool. they rerouted my new clutch cable and checked my carb for free. and there pretty good on pricing of there parts and ridin gear to.its nice to know that there is someone in the business that will treat you good all the way around. unlike the big guys like FayMyers and Colorado Powesport to name a few.) i tryed using a chem dip to clean the head it didnt get all the carbon off but i will try to clean the cylinder wall myelf first though. anyway ill keep you posted.

 

[dirt bike dave]

On the 91-94 KDX250, use a head gasket from an '88 KX250. It is thinner and will give higher compression and more power. Pump premium fuel will still work fine.

 

[JasonWho]

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[codyKDX250]

hey JasonWho i got the pics you wanted but how do i upload pis onto this thread.

 

[JasonWho]

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[codyKDX250]

I don't think you can since you are not a subsrciber. Do you have Webshots, MSN photos or just plain old personal web space?

how do you become a subsrciber im registerd isnt that the same thing? ill check on the MSN thing

 

[Matt90GT]

Be sure to clean the power valves and replace as needed! Also replace the lower shock bearing (you may need a new Unitrac link also).

Once you get the bike back running with the KX .26" headgasket, here is the jetting specs you need for the bike:

Jetting: 38/158 , R1367H needle 3rd clip from top, #6 slide

 

[JasonWho]

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