1989 KDX 200 Basket Case Project

rbates9 · Post by **rbates9** » 06:15 pm Jun 08 2012

That piston don't look so great.

Post by **Julien D** » 06:57 pm Jun 08 2012

Not so great = hammered hell. That needs to come out, now. As far as the reed cage, new reeds, and do whatever you have to to clean all that old gunk/sealant/whatever it is out.

Thrahl · Post by **Thrahl** » 11:12 am Jun 09 2012

Alright so this morning I decided to tear into the engine. It was my first time ever even seeing the inside of any engine.
Surprisingly though, everything went butter smooth. Was super simple and I didn't even mess anything up

Anyways, here are the pics. From some research that I have done on reading pistons, it looks like seizure or running without oil or something.
You guys tell me what you think.
Piston/Head
http://i70.photobucket.com/albums/i93/x ... M_2717.jpg
http://i70.photobucket.com/albums/i93/x ... M_2718.jpg
http://i70.photobucket.com/albums/i93/x ... M_2720.jpg
http://i70.photobucket.com/albums/i93/x ... M_2721.jpg
http://i70.photobucket.com/albums/i93/x ... M_2733.jpg
http://i70.photobucket.com/albums/i93/x ... M_2732.jpg
Cylinder
http://i70.photobucket.com/albums/i93/x ... M_2725.jpg
http://i70.photobucket.com/albums/i93/x ... M_2726.jpg
http://i70.photobucket.com/albums/i93/x ... M_2727.jpg
http://i70.photobucket.com/albums/i93/x ... M_2738.jpg
http://i70.photobucket.com/albums/i93/x ... M_2737.jpg
http://i70.photobucket.com/albums/i93/x ... M_2736.jpg
http://i70.photobucket.com/albums/i93/x ... M_2735.jpg
http://i70.photobucket.com/albums/i93/x ... M_2734.jpg
http://i70.photobucket.com/albums/i93/x ... M_2730.jpg
http://i70.photobucket.com/albums/i93/x ... M_2729.jpg

I did a direct link to them instead of posting them because I took so many. It was really hard to take decent pics of the cylinder so there are lots of different angles so you can get the full picture.

The head looks great to me. No nicks or discoloration. The piston looks good right at the intake port but lots of discoloration on the sides. You can feel the marks on the piston a little bit.
The cylinder has a large area at the intake that is very discolored and you can feel the scoring. There is also one strip that is deeper than the rest. It looks like bare aluminum there.
The exhaust side is slight discolored but completely smooth. Aside from that there is just slight discolorations in various areas but its smooth.

I obviously don't know a lot about cylinder/piston condition but a replate and new piston looks like it may be necessary to me unfortunately.

Post by **SS109** » 11:44 am Jun 09 2012

Thrahl wrote:...but a replate and new piston looks like it may be necessary to me unfortunately.

I agree. That cylinder looks real bad.

Thrahl · Post by **Thrahl** » 12:49 pm Jun 09 2012

Well I think I may know what caused the problem.
I think the engine may have been severely overheated, causing a seizure on the intake side and melting the plastic of the reed box (see previous pics).

What caused this was the fact that the water pump impeller was screwed in literally about a turn. When I pulled the cover off the bolt just fell off.

Add to that it looks like the seal between the water pump and crankcase was bad and the PO though it would be a good idea to just put some sealant on it.

So a new seal will be in order and it looks like a new impeller too unless I can clean this one up good.

david · Post by **david** » 02:52 pm Jun 09 2012

Impeller still looks good.

Thrahl · Post by **Thrahl** » 04:09 pm Jun 09 2012

david wrote:Impeller still looks good.

The manual says to replace if it has corrosion. I'm gonna clean it up good and see what I think then.

What does a replate generally run for with these bikes?
Everyone seems to like Langcourt and say that US Chrome is no good.

A new piston kit on eBay is about $95 and gasket kit $22.
I figure if I do a replate and new cylinder, I might as well bite the bullet and just do the whole thing right.
Strip everything down, beadblast, repaint, etc.

This won't be much of a "buy it cheap, ride for a while, and sell it" and more like a bike that I put some money into and keep it for a long time.
Still want to try and keep it under $1000 total though.

Post by **Julien D** » 04:12 pm Jun 09 2012

Your diagnosis is probably correct. Looks like it overheated, and siezed on the exhaust side. Now that you mention it, looking back on the reed block pic, it does look melted. That was HOT. I suppose you'll be needing to replace that as well. Maybe post up in the wanted section on that, as someone may have a spare if they've put in a boyesen or vforce cage.

A re-plate and top end kit is in order. It's disappointing, I know. I went through similar experiences on my '89. After you get it solid, it's one of the most rock solid 2 strokes ever built. Your initial investment will be worthwhile. Re-plating will run you about $200. Doesn't look like it needs welding, so that's good.

Post by **SS109** » 04:23 pm Jun 09 2012

I have an extra reed cage. I'll send it out with that carb. No charge. The reeds are Boyesen Power Reeds that are still in decent shape. I don't know how much life they have left but it should get you by for a while.

Thrahl · Post by **Thrahl** » 04:38 pm Jun 09 2012

SS109 wrote:I have an extra reed cage. I'll send it out with that carb. No charge. The reeds are Boyesen Power Reeds that are still in decent shape. I don't know how much life they have left but it should get you by for a while.

Wow that would be awesome. I really appreciate it.
If I were to get one on eBay they would have who knows how many hours already on the reeds so I'd probably have to buy new ones and it would just add up quick.

I'm gonna take a look at the clutch this weekend and see if that is going to need work too. Hopefully not.
I'll also give Langcourt a call this week and see what that is going to total.

Post by **SS109** » 04:49 pm Jun 09 2012

No problem. We try to help each other out here at KDXrider. If you need other parts definitely post up as one of us just might have something laying around!

BTW, you will want to take the cage apart and give it a good wipe down as it has been collecting dust for over a year now.

Thrahl · Post by **Thrahl** » 09:07 am Jun 10 2012

I took a little closer look at the piston today and looked up the part number.

It is a Wiseco. Probably not a ton of hours on it either judging by the lack of carbon below the rings.
It's too bad really.

Thrahl · Post by **Thrahl** » 11:45 am Jun 10 2012

Also took the clutch apart to make sure it was in order. For the most part it looks good to me. Maybe even replaced at some point?

One of the things that caught my eye was a crack in the basket spacer/bushing thing.

It doesn't look like it goes all the way through. I can't really tell if that thing is removable/replaceable. I tried pushing on it a little and it didn't move.

I don't have a mic to check the thickness of the plates and I don't know what worn would look like so maybe you all can give it a shot.
The first steel plate has black marks on it that don't rub off.

The steel plates behind it look much better.

This is the first friction plate.

Here is the second.

The first friction plate looks different than the others. It has those swept rectangles while the other plates are just regular rectangles. Is this normal?

Post by **dfeckel** » 03:08 pm Jun 11 2012

Yes, the top plate is different that all the other friction plates. On my E-series, the top plate installs into recessed notches on the ends of the basket fingers. Your basket does not have these recessed notches for some reason.

As for the cracked bushing, it should be removable just by sliding out of the basket.

KDXrider1989 · Post by **KDXrider1989** » 12:00 am Jun 12 2012

dfeckel wrote: Your basket does not have these recessed notches for some reason.

My '89 does not have those "recessed notches" either, nor did my other '89 KDX that I used to have

KDXrider1989 · Post by **KDXrider1989** » 12:02 am Jun 12 2012

I also wondered why the top plate is different than the others when I inspected my clutch 2 days ago

Thrahl · Post by **Thrahl** » 09:55 am Jun 12 2012

Well the bad news just keeps rolling in unfortunately.
I contacted Langcourt and sent them the photos of the cylinder and they said that it looks like it may have detonation damage.....which costs $250 to repair.
They said that is a worst case scenario though and nothing is certain until they see it in person.

I also took my KIPS system apart which was a pain because of the carbon build up.

Then while I am cleaning everything up I see this.

I guess it is pretty common for these to break because they are aluminum and the rod is steel but that one little piece costs $37

Anybody have an old one they could sell me for a more reasonable price? It is the left valve, the one without the groove.

A little bit of good news though. My side plastics finally came in today.

They look great. The only blemish is an exhaust burn on the right one that isn't really noticeable.
They were pulled off a KX500 and only cost me $25 on eBay too so that seems like a steal to me.

Overall though it isn't looking good. I totaled it all up and if I don't find anything else wrong with the bike (doubt it), the entire project is going to total about $1100 to get it 100% again.
When you consider that I have basically bought the cheapest parts available, got lucky with people giving/selling me parts cheap, and done all of the work myself, it really isn't a good deal.
This project is now on a paycheck-to-paycheck timeline too since I have run out of money so updates will be slower probably.

kyledsmith87 · Post by **kyledsmith87** » 12:01 pm Jun 12 2012

Your absolute best bet on these is to get a machinist to make the guides out of bronze. I am in the UK, but for a few bob I could make some and send them to the states (your bike is starting to lose its cheapness appeal, just like mine did :P), if you keep the bike a while it will pay off.

Post by **Julien D** » 12:36 pm Jun 12 2012

kyledsmith87 wrote:Your absolute best bet on these is to get a machinist to make the guides out of bronze. I am in the UK, but for a few bob I could make some and send them to the states (your bike is starting to lose its cheapness appeal, just like mine did :P), if you keep the bike a while it will pay off.

If you are interested in getting these machined, let me know. I would be interested in a large batch which would then be sold by the set through the site.

Post by **SS109** » 02:22 pm Jun 12 2012

Julien D wrote:
kyledsmith87 wrote:Your absolute best bet on these is to get a machinist to make the guides out of bronze. I am in the UK, but for a few bob I could make some and send them to the states (your bike is starting to lose its cheapness appeal, just like mine did :P), if you keep the bike a while it will pay off.
If you are interested in getting these machined, let me know. I would be interested in a large batch which would then be sold by the set through the site.

No doubt. Even though mine are good I wouldn't mind have at least one spare set around if the cost was reasonable.

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