Furstrated >;(

[korupted]

I saved up alot of money, bought me a 2001 kx 250...

Ran fine.. then started fouling plugs.. now wont crank
So Im ****ed and frustrated and want to basicly just beat it.
I ordered new parts, new head pipe, top end rebuild kit, new tire, new front sproket, new air filter.


And im taking it apart, so I can rebuild it.
Is it time for a rebuild? Here are some pics. I took off the cover of a part of the engine is its got hard black tarish like substance all over it

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Im in desperate need here, I dont know whats wrong
And I know if i put it back together it and take it to some shop there gonna charge me probably 500-1000$ to fix it because shiops around here are insane.


so please, can anyone help me? If helped and definatly got my bike working strong, Best beilieve Ill show my gradtitude and swing some cash your way probably through paypal

[QKENUF4U]

thats just exhaust from the power valve. nothing you can do about it. its normal.
now the parts you need to worry about are the cylinder/rings/piston/rod bearing. ya really need a FACTORY SERVICE MANUAL to do this correctly. to many tricks/tips to explain over the net.
good luck

[korupted]

but all that hard buiilt up black tarish stuff is fine in the power valve?

[QKENUF4U]

its normal but you will need to pull the power valve apart and clean it all. make sure its clean and moves freely. i pull it apart and then use my wire wheel to clean it. thats why you need a factory service manual

[Chazbo]

It all looks normal. Get a Clymer manual. When you remove the cylinder try not to mess up the mating surfaces, or you are gonna have leaks. Get a new engine gasket kit and some gasket sealer. Cometic has some good stuff.

Get that cylinder off the bike and then explore the power valve. Clean it up real good. Any broken parts in there obviously have to be replaced. All that black buildup needs to be removed. Make sure that if you are removing the cylinder, that you put something in place around the rod so
dirt doesn't get in the engine.
I took my KX cylinder to a machine shop and had the guy hone it without having to get a larger piston.

Next, if you are fouling plugs, you need to check your fuel/oil ratio and you jetting depending on the altitude that you ride. There are many articles on jetting.

What plugs are you using?
The manual calls for a BR8EIX Iridium plug. I have used this, but they are expensive.

I now run BR8EG and have not fouled a plug since I changed it.

[KDXGarage]

The clymer manual stops at year 2000. Look for the 1999 - 2002 KX125 / KX250 manual on Rockymountainmc.com for $30.

You need to clean the power valves with something like E-Z Off oven cleaner. Don't leave it on aluminum for more than 10 minutes before rinsing. Steel is OK.

Stock cylinders shouldn't be honed, as they are plated. A green scotch brite pad will clear off any glazing.

Once it is mechanically sound (check your reeds as well), then worry about jetting. Make sure you have the correct spark plug also.

[Chazbo]

I should have mentioned that I have a 300 kit on my bike. The piston measures at 72.95mm.

Korupted, let us know how it goes.

[nastyhabit]

You need to clean all the carbon build up in the power valve housing or the bike will not run properly. you should be cleaning that out every 30 hours as per the service manual.