1989 KDX 200 Basket Case Project

[Thrahl]

How's it going guys? I just bought a myself an '89 KDX 200 project bike yesterday and found this forum when researching about it.
It's rough, very ugly, and doesn't run of course but everything seems hopeful so far.
I figured I would make this thread to just document the work I will be doing on it and update you guys in the process and maybe get some feedback.

I am a poor college kid so the whole idea behind this project is to keep it cheap above all else.
I bought the bike for $350 on Craigslist (which is an amazing deal in my area) and I am estimating spending ~$300 on it but we'll see how that goes.
Anyways, on with the pics.








Right now to get it to run it needs a stator source coil and spark plug. Then to get it rideable it will need a throttle cable, throttle grip, front master cylinder, something done about the flat front tire, fuel line, air filter, silencer, and various nuts and bolts.
Plastics, fork covers, and reupholstered seat will come in time but aren't a concern at the moment.
So far I have the stator coil, throttle cable, grips, and spark plug ordered so they should be here sometime next week.

So far aside from the missing parts it seems pretty solid. I threw a random spark plug in to feel the compression and it feels good.
The rear brakes work great, the carbs are freshly cleaned and jetted, the frame is straight with only a little surface rust, the suspension feels great, the tires look brand new, the chain looks new, clutch works good, wheels look good, bars are straight, and the pipe is dented and a little rusty but nothing I can't fix.

It's gonna take some work but I think I can get this bike running good and looking good eventually.
I welcome constructive criticism so please don't feel you will offend me if I am doing something stupid.

[Julien D]

Bringing any KDX back to life is a good thing in my book. Good luck with the build, keep us posted. Oh, and welcome to KDXRIDER!

[dfeckel]

It sounds like all the major stuff is there and intact, so that's a good place to start. And all the little things that are missing can be had for peanuts on eBay or CL. Good luck! If you don't have to open up the motor for any reason, then you just might have a KDX for $600 or less.

[scheckaet]

what the hell are those tubes on both side of the subframe? grab bar for spinning back flips?

[diymirage]

what the hell are those tubes on both side of the subframe? grab bar for spinning back flips?

dont you get poor newby confused with that nonsence now. clearly the previous owner read this post http://kdxrider.net/forums/viewtopic.php?f=77&t=12132 and decided whatever they are, if 2 is good 4 is better
but from the looks of it i'd say they are bar ends that go on bicycle handlebars


looks like you got yourself a nice project there Thrahl with a little elbow grease that puppy will be running like new in no time
(being hopefull the previous owner didnt just slap that sticker on but also installed some wiseco parts in it the engine just might be in pristine condition)

im not sure what i am more excited about, the fact another KDX is being restored or that there are actually still college kids out there who dont just waste their time playing video games but actually do something productive

[Thrahl]

I posted an update again yesterday but maybe I broke the rules or something because my post got deleted with no explanation (It was a pic of a dead brown widow that was living in the foot peg)
Anyways, yesterday I basically just got her a little more cleaned up, cleaned out and repacked the front wheel bearings as best I could, removed the airbox (is it supposed to be a PITA?), took some steel wool to the rotors, and a few other small things.

It sounds like all the major stuff is there and intact, so that's a good place to start. And all the little things that are missing can be had for peanuts on eBay or CL. Good luck! If you don't have to open up the motor for any reason, then you just might have a KDX for $600 or less.

Yea hopefully I won't have to get into the engine. I have never even seen the inside of any engine personally so it would be a completely new learning experience (may not be a bad thing).
I just don't want to open it up and realize it needs a replate. That would kind of kill my budget idea.

what the hell are those tubes on both side of the subframe? grab bar for spinning back flips?

Haha. My buddies and I just figured they are extra grab handles. Maybe for shorter people who can't comfortably lift from under the seat
They will be coming off probably today though.

looks like you got yourself a nice project there Thrahl with a little elbow grease that puppy will be running like new in no time
(being hopefull the previous owner didnt just slap that sticker on but also installed some wiseco parts in it the engine just might be in pristine condition)

Hmm, I never even thought about that sticker. If I end up having to open up the engine we will see I guess.

[Julien D]

I posted an update again yesterday but maybe I broke the rules or something because my post got deleted with no explanation (It was a pic of a dead brown widow that was living in the foot peg)

That was me, sorry. It was an accidental deletion. I posted to the thread by mistake with my not-so-smart phone, and was trying to delete that post and deleted your update as well. Please re-post it! Unfortunately there is no un-delete on the forums... :(

[Thrahl]

I posted an update again yesterday but maybe I broke the rules or something because my post got deleted with no explanation (It was a pic of a dead brown widow that was living in the foot peg)

That was me, sorry. It was an accidental deletion. I posted to the thread by mistake with my not-so-smart phone, and was trying to delete that post and deleted your update as well. Please re-post it! Unfortunately there is no un-delete on the forums... :(

It's ok. Wasn't important anyways.

Today I decided to take the rear wheel off and inspect the bearings since it felt a little sluggish turning it by hand.
When I pull it all apart I realized the wheel wasn't even spinning on the bearings, the bearings were spinning directly on the axle
The rear bearings look almost brand new compared to the front and felt smooth, just really hard to spin.
Then I realized that when you turn one bearing it was also turning the middle spacer and the other bearing at the same time. That isn't normal is it?

It seems like someone pressed the bearings in too far and they are kind of crushed together making it difficult to turn them.
If I could just push one back a tiny bit I think they would be golden but since the spacer is exactly the same size as the inside of the bearing I'm not sure how I can do it nice and evenly.
I might try a little expanding rubber plug wedged in one and hitting it with a hammer to knock it a little loose. Any better ideas?

[Julien D]

I did enjoy the widow photos. You should post those back up at least, lol.

Sounds like you might should just replace those bearings.

[Thrahl]

Alright well here are those pics.



I was cleaning around the foot peg area and noticed there was a web and an egg sack down there. When I sprayed it with poison she came flying out very pissed off.
I've lived in Florida for my whole life so I am used to widows but this was on of the biggest I have seen.
Then as I was cleaning the engine there was another right by the exhaust pipe. That was a little smaller but was a black widow (as opposed to the brown widow in the photos). Didn't get pics of it.

And yea on the bearing situation, I am going to try and tap it a hair out with a brass rod and if that doesn't work then they will be getting replaced.

[Thrahl]

I didn't really think too much about this before but I don't need a lighting coil if I'm not running lights right?
Both coils are missing but since the head light and tail light are missing as well, I wasn't going to replace everything.
I have the source coil on the way and I am planning on just installing it by itself.
Will it give me any issues on how the bike runs?

[Julien D]

I can tell you from experience, it runs fine without a lighting coil.

[Thrahl]

I can tell you from experience, it runs fine without a lighting coil.

Ok that's good. In the Best Mods sticky it says

A high output lighting coil also has an effect on performance by exciting the ignition coil to a point. You will notice how much better your bike runs with a new high output lighting coil.

and that kind of got me worried.

Also, I have read about people doing the "air box mod" and they say there is something under the lid that you have to relocate.
Well my air box doesn't have a lid on it. For electricals it is set up stator -> cdi box -> ignition coil. I'm not missing anything am I?

[Julien D]

Nope, you're not missing anything. Later models have a voltage regulator mounted to the airbox lid. Your 89 didn't come with a VR. If you ever decide to fix and run the lights I would recommend adding one. I guess someone has already done away with the lid on your airbox, and that's just fine.

[Thrahl]

I was looking over the service manual today and realized that my carburetor is very different from the one they are showing.
It's a Mikuni (are the stock ones?) and has a totally different throttle slide and float assembly.



There are basically no identifying marks on it aside from a few very small numbers.



Also, those little nipples sticking out the side are vents right? What do I need to do when everything is hooked up, just put some hose hanging off of them?

[Julien D]

Yup, looks like someone swapped the carb. It'd be nice to find a 35mm PWK to put back on it. I'd say its preferable to that mikuni. Jetting may prove to be a challenge. And yeah, those nipples are for the vent lines. They usually run down between the swingarm and frame.

[KarlP]

Today I decided to take the rear wheel off and inspect the bearings since it felt a little sluggish turning it by hand.
When I pull it all apart I realized the wheel wasn't even spinning on the bearings, the bearings were spinning directly on the axle
The rear bearings look almost brand new compared to the front and felt smooth, just really hard to spin.
Then I realized that when you turn one bearing it was also turning the middle spacer and the other bearing at the same time. That isn't normal is it?
It seems like someone pressed the bearings in too far and they are kind of crushed together making it difficult to turn them.
If I could just push one back a tiny bit I think they would be golden but since the spacer is exactly the same size as the inside of the bearing I'm not sure how I can do it nice and evenly.
I might try a little expanding rubber plug wedged in one and hitting it with a hammer to knock it a little loose. Any better ideas?

It is normal for your bearings to be set like that, with the middle spacer touching both left and right inner races. The outer bushings also push on the inner races and everything gets clamped between the swingarm ends.

How do you know the bearings were spinning on the axle? That will happen if the bike is up on a stand and the axle nut is loose.

Once you tighten the axle nut everything clamps together through the inner bearing races. The outer bearing races suspend the wheel.

Clear as mud?

[Thrahl]

It is normal for your bearings to be set like that, with the middle spacer touching both left and right inner races. The outer bushings also push on the inner races and everything gets clamped between the swingarm ends.

Hmm well then maybe that isn't my problem and the bearings are just bad.

How do you know the bearings were spinning on the axle? That will happen if the bike is up on a stand and the axle nut is loose.
Once you tighten the axle nut everything clamps together through the inner bearing races. The outer bearing races suspend the wheel.
Clear as mud?

I know because there are nice big shiny marks on the axle where the bearings sit
The axle nut was tight right up until I took the wheel off and realized what was going on.
It was hard to tell if maybe once there was weight on the rear wheel it would spin the bearings but they are so hard to spin by hand it just doesn't seem right anyways.

I have loosened them up a hair and they seem to spin slightly better and will turn if I spin the wheel on just the axle.
I think I will get them as good as I can and then once the bike is functional I will get new front and back bearings because they are pretty cheap.

[Thrahl]

I was messing with my rear wheel a little more and realized that my chain isn't meshing properly with my rear sprocket.


There is a fairly large gap there and I definitely don't want to be running it like that.
As I dug a little more I realized that the rear sprocket is not stock. It's a JT 49 tooth (
Both front and rear sprockets look fine. When I measured the chain, it was about 324mm over 20 links which is just barely out of spec.
But is that really enough to make that large of a gap or is something else going on here?

[dfeckel]

That does look weird. The link pins should be centered over the grooves in the sprocket, but they are clearly off by a couple millimeters. I'm not sure what's going on here. I might take all tension out of the chain and see if you can get the chain to mesh properly with the sprocket. If you can't, then you might have either the wrong size chain or sprocket.