2010 KX250F + 1994 KX500

[agentwilliams]

I'm new here and stoked to see the forums back up. Thanks to all of the people contributing.
Here is my project. 2010 KX250F and 1994 KX500.

The 250 was bought in Ohio on eBay and the 500 was bought near Indy from Cl. I'm in Saint Louis, but I got both bikes in 1 road trip!

Although it was bought under the description of "it ran when I parked it 8 years ago" the 500 is in need of a rod and is due for a top end and cylinder replating. It looks like it ran without premix. Other than that, it appears to be pretty low mileage.

The plan is to build it, refine it for a year, and race the BAJA1000 in 2014.

[sandblaster]

Did you day the B word
That would be some ride.
Take lots of pics and post often as we all like to see builds progress.
Thanks!

[agentwilliams]

Did you day the B word
That would be some ride.
Take lots of pics and post often as we all like to see builds progress.
Thanks!

HAHA - yep- da "b" word! I saw your business link in your profile and will reach-out if I need something.
I'll keep up with build pics.

[agentwilliams]

I gutted my engine is gutted so the lump is lighter going in and out of the frame.
Surprises - The "new" cylinder needs plating... The lower rod bearing is toast. The cases need a small repair where it looks like the rod went - not too bad. Overall, not as bad as it sounds, but the cylinder is a real bummer.

I cleaned it up with elbow grease and detergent, but the aluminum is stained. I bought a bead blaster to clean up the cast parts. I'll wait until I get the frame finished to make it too clean.

SH is out of KX500AF exhaust so I'm thinking of cutting the inlet of the donor bike's pipe off (it's a thrashed FMF) to give me something to mock up clearances in the Y area.

[sandblaster]

I did the same thing with my mock up engine.
Gutting them out makes a huge different when taking them in and out.

[agentwilliams]

I played a little with the engine and frame. Here are some loose mock-up pics.

[sandblaster]

Looking good!

[USMC 500]

You're off to a good start......can't wait to see what this thing ends up looking like

[LundMx]

How does the clearance look like from spark plug to tank? Im curious for myself as well since we have almost the same project going on 

[sandblaster]

NGK BR8ECM

[USMC 500]

Chuck Norris brushes his teeth with a kx500 conversion toothbrush.....

[agentwilliams]

Progress at last!
I teamed up with my old moto-bro Ray from goldmedalwelding.com and made the brave cuts on the frame.
The stock "y" was re-used, jfab frame rails are in place. We will re-use the stock motor mounts, relocated for the K5 of course.
When he does the finish welding, i'll post some better pics. This man can weld!

[motopunk]

NGK BR8ECM

i use only this plug in my 250, 360, 500 ... its easy handling and on the big engines it gives the right clearance to the tank..

nice bikes on the first look,     ... its a little bad that the k5-engine is worn out, but new rod,piston crank bearings seals and plating and you´re back in business and it make sure, you have a great engine in the af-frame if you finish the projekt... 

service honda use a light modyfied cr500 exhaust on their kx500af-bikes... you can buy a aftermarket cr500 pipe and weld the right kx500-flange on it for the cylinder-fitting . thats easier as cutting off and welding together the whole old k5-pipe ...

[agentwilliams]

Thanks Motopunk. The CR pipe is becoming necessary with SH not having anything available for the last 3 months!
What year of CR pipe?

[LundMx]

Go with 89 to 01 cr500 pipes. Fits good on the 09-13 kx250f frames. I will try to post photos of how i welded my pipe to fit. Should be the same for you