fouling plugs on a KX 250..help

[mikeskickinit]

Well I recently had my bottom & top end all re-built on my '98 KX 250 and had the carb cleaned as well. Every time I go to start the bike, it either doesn't start at all or it will start and bog down right away and die out...then I need to put a new plug in and then it starts first kick. I tried burning the tip of the old plug etc but it doesn't work.

So every time I go to ride my bike I need to put a new plug in it..Once in a blue moon (like this weekend) I went out and started it 2nd kick and rode it around..Went out the following day and started no problems. Just yesterday (Monday) go outside and it doesn't start at all. I do shut the fuel off when I'm done riding it.


Does anyone know why? I was told it could be something about not setting the plug??


I'm using BR8es plugs in the bike currently. Oil ratio I'm using is 32:1. Any help would be great..thanks!

[evoluvin]

this si what i did... it may help... i mix one small bel-ray H1R to 5 gallons of gas and i also use a hotter plug witch is a br7es.... also make sure when u start it u only leave the choke on for less then a min. also yoou always have to keep reving these bikes and keeping the RPM's up you cant let it sit there idleing... also is your crankcase oil level staying the same? If not it could be crankcase seal.. also take a look at my thread i posted last week... http://www.kawasakimotorcycle.org/fo...help-asap.html
Hope this is some help....

[KickassKX125]

The main reason bikes foul plugs is because they are running rich, changing plug temperature is a quick bodge for if you have no time, take the time to read the jetting guide and jet your bike, it might be a pain in the rear but it is worth it - especially if you ride at the same place or a similar altitude because you won't have to re-jet unless you change either the pipe or reeds .

[mjsedg]

Will changing reeds really make that much of a difference. Right now my bike is jetted dead on, but over the winter I plan on doing a top end and a new set of OEM style reeds. Think I'll still need to re-jet?

[KickassKX125]

If the reeds are going to be the same then it will be ok, what I meant was if you get the boyesen or vforce or any other performance type, sorry I should have mentioned that.

[mikeskickinit]

Originally Posted by KickassKX125

The main reason bikes foul plugs is because they are running rich, changing plug temperature is a quick bodge for if you have no time, take the time to read the jetting guide and jet your bike, it might be a pain in the rear but it is worth it - especially if you ride at the same place or a similar altitude because you won't have to re-jet unless you change either the pipe or reeds .

Yea, right now I am leaning out mixture. I was doing 3:1....and worked my way down to 2:1 right now and the bike seems it be running better. I am going to ride it today and see if it starts up.


and I did go ahead and jet the bike previously.

[Saleenguy]

Originally Posted by mikeskickinit

Yea, right now I am leaning out mixture. I was doing 3:1....and worked my way down to 2:1 right now and the bike seems it be running better. I am going to ride it today and see if it starts up.


and I did go ahead and jet the bike previously.

2:1 what?

Buy an air/fuel gauge, slap it on, and know what you have for mixture.

They are inexpensive, draw so little power, any bike can run one, and you ae then able to jet it perfectly at every rpm and load.

I put them on all of my high performance bikes.....they are worth their weightin gold, and you will have the piece of mind of a perfect running bike, that you are not going to blow the motor up in.

[mikeskickinit]

Originally Posted by mikeskickinit

I am going to ride it today and see if it starts up.

2:1....2 ounces of oil, 1 gallon of gas.



I took the bike for a rip Monday. Put choke on started up 2nd kick no problem and ran fine...so far, so good!

[jdager]

hi, could you please explain the air fuel gauge and how they work? it seems like an awesome idea, I might like to try one. where does it install, what should the readings be on a 125, and how do you use that to help jet the bike?
thanks,
JIm Dager

[gaz]

hey if 1 gallon is 128oz then (2oz:128oz) is 1:64 (oil:gas). I wouldn't be running the bike that lean on oil. I run mine at 40:1 (gasil) and thats using Motul 800 oil. You might find the motor running hotter and may eventually seize or need a rebuild sooner.
3.5oz:1 gallon = 40:1 ratio
4.0oz:1 gallon = 32:1 ratio
we use metric so I'm only guessing!
How many oz is a small Belray H1R?? , if its 1 pint then that to 5 gallons is 40:1 which is ok.
Leaning the gas/oil is not the same as leaning the air/premix gas that is done in the carby. Pick an oil/gas mix between (32 - 40 : 1) then work on the carby jetting. Its a pain but worth it when you get it right.

[Saleenguy]

Originally Posted by jdager

hi, could you please explain the air fuel gauge and how they work? it seems like an awesome idea, I might like to try one. where does it install, what should the readings be on a 125, and how do you use that to help jet the bike?
thanks,
JIm Dager

The probe goes into the pipe, and then a wire to the gauge.

it gives you instant measure of your air/fuel ratio.

depending on the bike, and your useage, you can run it a little more or less...but about 13 to 14 feels good for me most of the time.