Kx250 Project Rebuild

So after a few months without a dirtbike, and itching to have 2 wheels under me again, I decided to take on another bike rebuild project. I initally wanted a thumper, but I didn't like the maintenance intervals and too predictable power-band. I stuck up a wanted ad on good old craigslist for a 2 stroke motocrosser that needed work, and a few days later got an offer for a 2001 Kx250 for $400. I snatched it. Owner said it locked the lower main bearings up and needed some TLC. How it looked when I brought it home in the trusty '88 Ranger.







I was glad to see the front and rear rims are Excel laced to stock hubs, it has Vforce 3 reeds, and Protaper 1 1/8 bars with a matching top tripple. The left radiator is shot, the inner clutch basket is broken, kicker level is broke and the stator is shot. All these will be sourced on eBay, craigslist or somewhere else. I'm looking for an entire engine too if anyone has a blown one their looking to get rid of.









What I found: Sprockets and chain are good, crank is a Hot Rods with no play in the rod, rear shock is blown, so I popped it apart and cleaned the seals and it stopped leaking, forks are leaking (I'll see if I can clean those seals too), rear rim is missing a spoke, tranny is in awesome shape, clutch is good, plastics will make a good learner pair, and frame will need to be re-painted. All in all, I think I got a great deal! It looks crappy right now, but will go together nice. I'm planning to do some port matching/polishing of my own. More to come. :cheers:

Cool. Good luck with it. I see it has a Renthal upper clamp. That is a good item!

looks like you got your hands full on that one. shes a dirty girl.

That should be a fairly easy rebuild, looks like you know what you're doing. I would highly recommend replacing the crank though. Fine bits of metal may have entered the lower rod bearing.

I'm going to dip this one in diesel and try to get any metal out of it. I can't see anything in the bearing, and it doesn't have any catch, who knows. She's pretty dirty, all the shock oil soaked the linkage and frame, and the carb overflowed quite a bit. I'm thinking about going with a black frame, I have a sandblaster that will fix the rest of this oily/greasy mess. I was pleased to see the transmission was coated in golden colored oil (looks to be changed regularly), and all the shift forks and dogs look to be good.

Edited by charlevoixboy

Good find!

Good find!

Thanks! I love these types of projects, once done I'll have been over every piece of the bike, and know it's done right

good luck:thumbsup:

i love a rebuild thread with pleanty of pics:thumbsup:

good luck:thumbsup:

i love a rebuild thread with pleanty of pics:thumbsup:

I'll keep the pics coming. Since I'm repainting the frame, what color combos should I go with? I'm keeping the black wheels, and that's it lol The frame, is getting repainted new plastics ordered and new seat cover ordered. I'm not a huge fan or graphics because they are expensive and get nicked up easily. I was thinking black frame with green plastics, or maybe white? Also what do you guys recommend for paint? Rattle/compressor. I'm not going to PC. Thanks!

Personally I don't like black frames. I'd go green or silver.

Have you considered just cleaning the frame and maybe touching it up?

I am pretty biased on "the stock look", though. :cheers:

I would like to touch it up, but the entire bottom of the frame has the faded paint worn off, and there's countless chips everywhere. I'm going to repaint it for sure. I'm really leaning towards black frame, silver swinger, black tripples, and the black wheels. Still not sure on plastics.

Check some of the past rebuild threads. All black or nearly all black has been dome several times, so you can get an idea of how it looks.

Well come to find out the bike's actually a 2000 model, with a non-theft VIN. That's always nice. I bought a Harbor Freight HVLP gun, and used that to lay the color. I was very happy with the results, and will use this gun to paint my car in the future. Here's how it came out:








Pretty good for a $50 gun! ( it's this kit: http://www.harborfreight.com/professional-automotive-hvlp-spray-gun-kit-94572.html )

Nice job! I use inexpensive guns too. I picked up a $20 detail gun 1.0 tip for my frames. It's not like you're painting a hood or something. What paint did you use?

Looks good! Good job.

Ya, the gun I used worked really well. It's automotive acrylic enamel, 3 coats thick.

Another update:

I think I have the forks fixed, a piece of dirt was in each seal causing them to leak. I'll have to top the oil off once she's running. In typical KX fashion, the rear linkage bearing was toast, so I'll be ordering a new one of those too. The shock was rebuilt by myself, filled with ATF and charged with air (150PSI) We'll see how that setup works, it's easy to fix if it performs bad. I found that the gastank nut inserts are spinning freely in the plastic, so in the future that will need attention also. My plan is to assemble this bike bare bones, and once running nicely worry about the other things. I'm tight on cash lol

Please PM me if your have any parts that will fit this KX too, I'm in need of some things.




ATF in a shock?? That seems a bit thick.

You may to switch to nitrogen in the shock.

ATF is something like 10w, ok for some street bikes. MX shocks typically use 2.5w, so you should really change that out.

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