My 1999 KX250 Build

[mjowen]

Hey, everyone -

Figured I'd post to keep track of the progress i make on this.

I've been looking for a project bike to give me something to do and decided i'd get into the dirt world. Was searching craigslist on saturday and stumbled upon a 1999 KX250 a couple hours north of me. The motor was locked and the guy was selling as is. Ended up making an offer and after a little back and forth we agreed on 500 bucks for it. So, i finished my mimosa and headed up to Cheyenne to pick it up.

Again, this is my first jump into the dirt world and my first 2-stroke ever. Not quite sure what i'm getting myself in to but we'll see how it goes haha.

The bike is in alright shape overall but definitely needs some mechanical work and some TLC.

The plan for the bike is as follows:
- Top and bottom end rebuild
- All new fluids, plug, filter, etc
- New plastics
- New graphics
- New chain kit
- Possibly powdercoat the frame (we'll see how frisky i'm feeling); prior owner painted it black and it's of course chipping now. Might just sand it and repaint it, not sure.
- New front and rear tires
- General cleaning

Heres a quick pic after unloading it and putting it in the garage:


As of tonight, i've accomplished the following (which i've hopefully done right):
- removed the seat and plastics
- removed the tank
- removed the exhaust
- drained the coolant and oil
- removed the radiators
- removed the carb (although i left it mostly connected)
- removed the top end

Someone obviously started this project and didn't do anything with it. First off, there was no gasket on the top of the head. Second, once i got the top end off i found the piston to simply be sitting inside the cylinder, on top of the connecting rod. Needle bearing was inside the piston as well. I've got a list going of the parts and pieces i'll need to buy but i'm sure i'm going to be needing everyone's help since this is my first attempt haha...i've noticed a couple things such as a random hose missing on the carb, bolts missing, exhaust basically held on with the springs and two bolts, few other things; but i'll figure those oddities out later.

Here's how she sits at the moment:




The tear down has seemed to go just fine so far and i dont believe i've done anything wrong...at least i hope i havent haha.

Not quite sure what i'm going to do next...of course i still need to get the bottom end torn down but i still need to do a bit more reading up on this and then re-watch how to put everything back together.

If anyone is around Denver and wants to help a noob, lemme know haha

[Foxx4Beaver]

Not a bad buy for $500.
Before ya go any further, you should get yourself a Service Manual...if you haven't already. 

[mjowen]

Yep! I actually downloaded a PDF manual the day I brought it home haha

Did a little more work on it tonight:


Got the remaining plastics removed (minus the fork guards, will do those when i remove the fork and do the fork seals)
Chain removed
And removed the bottom end

I'm going to be going to a guys place next week saturday to split the case and figure the rest out (he's familiar with this, i'm going to learn lol)

Tomorrow or maybe next week:
- remove the sub frame
- remove the swingarm
- remove shock
- remove fork

Then i'll get some pics of the wiring so i know where it all goes and will remove that...then i'll have the powdercoat done.

Parts list is mostly together pending anything crazy with the bottom end. Hoping to have the parts ordered within a couple/few weeks and will then start putting it back together.

[umberto]

If you have not purchased your piston yet, consider getting a Wossner.  Several very knowledgeable engine builders on this site swear by them. I put one in my 500 conversion, and I was very impressed with the quality and finish. They also make very nice rods if you are going to rebuild the bottom end. On this site, Sandblaster or alward25 are Wossner dealers if you want to buy from someone you can trust.

[mjowen]

If you have not purchased your piston yet, consider getting a Wossner.  Several very knowledgeable engine builders on this site swear by them. I put one in my 500 conversion, and I was very impressed with the quality and finish. They also make very nice rods if you are going to rebuild the bottom end. On this site, Sandblaster or alward25 are Wossner dealers if you want to buy from someone you can trust.

I greatly appreciate the suggestion, man. I havent purchased any of the parts for the rebuild yet...i figured i'd get the full tear down done, write a parts list knowing what i need, research them, and then pull the trigger on parts.

I'll be sure to look into those wossner pins...i'll be doing the bottom end rebuild as well so will look at them, too!

[mjowen]

Alrighty...made a bit more progress as of tonight:



everything is mostly stripped. Still need to remove the pegs, those little plastic cover thingys on the frame, and remove the lower triple clamp (once i research how lol)

I'm in no rush though, things are just going to sit until next week when I split the bottom end and figure out whats going on inside there...then will order parts and start the rebuild.

After removing the shock and forks today i'll definitely be adding a shock service and fork rebuild to the list.

[Foxx4Beaver]

I did a rebuild on a '00 that I picked up as a basket case a few years ago...I love everything about it...

http://www.kxriders.com/forums/index.php/topic,10821.0.html

[sandblaster]

After removing the shock and forks today i'll definitely be adding a shock service and fork rebuild to the list.

There are some good "how to" vids on rebuilding your suspension on Youtube.

[mjowen]

I did a rebuild on a '00 that I picked up as a basket case a few years ago...I love everything about it...

http://www.kxriders.com/forums/index.php/topic,10821.0.html

Nice! I was able to quickly browse it today at work (about to go home) and will look at that in more detail later...gives me some hope for this one haha

There are some good "how to" vids on rebuilding your suspension on Youtube.

Yeah, i've read a few of them...havent looked into the forks much but did look at the shock. What is deterring me a bit is needing some special tools to get it done - i'll see if there is anyone near me that can help out as well.

I'll be going to a connections place on Friday to split the case to figure out the motor issue...then will order parts and start that rebuild.

[mjowen]

Alrighty...found out some great news with the motor today while doing the strip and most of the rebuild!!!

All that was wrong with the bottom end was piston skirt particles which prevented it from turning. Rod still in spec, and clutch basket fingers not too bad. Trans and everything else in real good shape. One of the KIPS valve shafts has some damage so ordered a new one and will replace that once the cylinder is back. Someone had already put a hot rods crank in at one point as well which was nice!

I apologize for the crappy pics...my camera was dead so i just took some snap pics and took some screenshots. Have to wait for a few parts to come in next week in order to finish up the motor...hoping to have it all done and top end done within a week and a half or so (depends on when parts get here).







Ordered as of today:

New piston kit
New water pump impeller
Bottom end gaskets
front and rear brake pads
new air filter
new piston sleeve (being done locally which is nice)
Couple oem parts needed such as some bolts and the kips valve shaft
new plug
carb rebuild kit

Next up:

frame power coated
rebuild the rear shock
rebuild the forks
order the chain kit
few more oem things such as exhaust coupler and bolts
new front and rear tire

then i'll start rebuilding and will decide on plastics and graphics

[mjowen]

Well - no pics at the moment but i'll get them up eventually...

motor is done. Just have to go get the top end from the shop which i had resleeved.

Shock has been dropped off to have a rebuild done (full rebuild for 130 including parts)

Frame is at the powder coater which i'll get back eventually...

Next up:
- fork rebuild with bushings, seals, fluid
- order the rest of the parts
- start putting her back together!

[mjowen]

Sorry for the late post...

took quite a while to get that frame back for some reason. Oh well...it's back and now i can continue!

Here is how the frame turned out:


I've got the front and rear tires mounted
new radiators and hoses in the garage
new filter in the garage
all new oem bolts
shock has been rebuilt
chain and sprocket kit in the garage

Now just waiting for the forks to be done...one of the forks was missing a valve assembly so ordered that today and will rebuild the forks. I also have a few new bearings ordered which i'm waiting for (front and rear wheel bearings as well as the steering stem bearings)

Next up:
- start putting everything back together
- rebuild the carb or at least clean it
- fix the gas tank mounts (one spins free and one is missing entirely)
- order the new plastics
- new graphics kit

[mjowen]

Just a quick update...

- carb cleaning done
- fork assembly ordered: apparently they're now discontinued so had to track one down rather than ordering it through the shop

I'll post a quick photo later tonight of the motor and rims/tires.

I've also shot a message out to a shop to get the swingarm coated - its really not in great shape as you can see in prior photos. So, we'll see what happens there!

[umberto]

Sounds like you are making progress.  Definitely more pics please.   

[mjowen]

haha, i will for sure...i've been slacking in the pic department lately. I got a new puppy about 6 weeks ago and he's been taking up quite a bit of my time as well!

Here are the issues i've run into so far:
- most of the bolts are all different sizes and head types so had to get all new
- missing some clamps here and there but wont know exactly until i start the rebuild
- missing a fork valve assembly on one of the fork tubes
- rear wheel spokes were shot so needed a new spoke kit on the rim before the tire could be installed
- wheel bearings were shot both front and rear as well as the swingarm bearings
- gas tank mounts for the plastics are stripped: one is missing entirely and one has a broken bolt inside and spins freely - will fix that as well
- sight glass is cracked but ordered a new one and will replace when i do a fluid change next

anticipated issues coming up:
- i ordered the valve assembly from rockymountainatvmc, they said one was in stock but i have a feeling they're going to tell me they dont have it as its been discontinued so will have to track one down
- i expect to have to replace the brake lines as everything else has been shot
- i believe the pipe that was on the bike is the wrong one as there were some fitment issues. I havent looked into it but will tonight or tomorrow: might sell the current and pick up a stocker if so.
- i expect to have some issues with the wiring and kill switch: it looks alllllll spliced up and crappy. so, we'll see.

I think that's it for now but i'm sure i'm missing something lol. Lots of issues here and there but overall has been a smooth...

I'll post some pics tonight or tomorrow...need to pick up the rims either today or tomorrow