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1991 KDX 200. New to me but it's been well ridden by my father in law.

He didn't ride it at all in the last 2 years so he figured I should have it. I took it out and went single track riding 4 times this summer (4 weekends, probably 400 miles total) and I'm wondering if it's time for her to get stripped and rebuilt. I'm pretty sure he didn't do a whole lot of maintenance.

The rear is starting to feel a little wobbly @ speed, so new bearings?

There is constantly oil coming out of the pipe, I'm running at the factory mix ratio and jetting since he never changed it. He mentioned he did use to run 40 or 50:1 (didn't really know) so I'm wondering if I'm just running it too rich or maybe it's time for the rings to get replaced?

Do you have to re-hone the jug when you replace the rings? (Sorry I'm a car guy).

Anyway, anyone with some maintenance tips or judgement speak up! I'm looking for something to do that'll be worth my while. Don't know much about 2 strokes though.

Thanks!
Andy

Hi and Welcome!
We need some pics!
Sounds like it needs a bit of tlc. Your best bet is to use the search feature here to find solutions to most/all the problems you're having.
You'll find out that you only have to scotchbrite the cylinder with a green scrubbie.
That the powervalve on that bike is prone to sticking and you need to use a high grade synthetic oil to stop that. I use Amsoil Interceptor at 40:1
You'll learn how to jet the bike properly and how to fix your linkage bearings.

So search away!
Again Welcome. You'll find lots of useful info from knowledgeable people

check all the bearings, especially the rear linkage, grease (use good thick bearing grease like bell ray, the so called "bearing grease" from the hardware store works but ever since I tried the bell ray stuff i will never go back!)
Jet the bike properly, some spooge is normal (oil from pipe), start here: http://www.kdxrider.net/forums/viewtopic.php?t=1156.
your shock may need a rebuild, at least a nitrogen charge.
I'd change the tranny oil while I'm checking things out.
have fun.

leaking oil is probably rings but on these bikes ( or atleast my 87 idk bout other years) you dont hone the cylinder you just replace the cylinder sleeve. most machine shops or engine shops will do this for $40-$50

hbgod wrote:leaking oil is probably rings but on these bikes ( or atleast my 87 idk bout other years) you dont hone the cylinder you just replace the cylinder sleeve. most machine shops or engine shops will do this for $40-$50

They don't come sleeved from the factory. They have an electrofusion bore that only needs to be scotchbrited to remove any glazing.
If it is to worn out; replating with nicasil is the way to go IMO.

Read up here on jetting, and a silencer repack. Spooge coming out of the pipe has nothing to do with rings. Get the jetting correct, and your spooge will be minimized. Check ring condition with a compression test. The top ends generally last A LONG time on these. I'd replace all the chassis/wheel/steering bearings...They get trashed quick if left ungreased.

Fletch, no im saying you wouldnt bore it youd just re-sleeve it. say if you get a bike thats been sitting for 12years like me nd the rings are stuck. you dont bore it. you re-sleeve it

Ok I understand, you can sleeve it or re-plate it. Replating is prefered by me as it transfers heat better and is tougher than a sleeve.
But I understand that people like to sleeve because they can just overbore and go.

I don't think your 87 came with a sleeve from the factory.

I still want to see pics

Fletch, im not sure of the history of the bike. i was helping an old lady clean out her basement and it was just down there from her husband it had been sitting for about 12 or more years. she was gonna throw it away so she said i could have it. but it looks completely stock. im going to do a rebuild soon.

Awesome start your own build thread so we can see the progress!

Hey guys thanks for the tips. I'll stop awfulizing and work on the jetting first! Try and dial in the forks, and I think I'm going to bite the bullet and replace all the necessary bearings and check out the linkage. I repacked (regreased) the front and rear wheels before I went riding this summer and it made me feel better but didn't really seem to help.

On to the pics.

This was a 2 part deal. Fix the ratty / neglected trailer, get trailer and bike. SO here is the trailer as is started:


after some stripping, painting, wiring, and cutting wood:


And the bike ready to go for the first ride of the summer:

Nice.

That's not an E bike, btw. Looks like a 95/96 H series.

hrmmm.. purchase date was feb 1991.. .so I guess at best it can be a 1992?

I always tell by the side of the frame. That purple looks like an h but maybe it was swapped on. A closer pic would be better. Nice trailer and Pilot though.... Good combination

Definitely an H series (95-06), and it looks decent.

H serie

Unless it's an overseas version of something I am not familiar with, it is definitely no older than 1995. You can see the perimeter frame, which the E series bikes (89-94) did not have.

I bet the 91 is actually a 97

Also, 87 is nickel bore stock.