'95 KDX rebuild project

[cokecan500]

Not sure if this is the right place, so please move if not.

I'm just now starting to fix up my 95 KDX 200. I thought it was going to be mostly simple stuff like oil, filter, coolant, brake fluid, etc but it looks like I've got a lot more on my plate than I anticipated.

When I tried to kick start it today, it was unexpectedly hard to turn. No problem, it had been sitting a while, so we pulled the spark plug and gave it just a little oil and continued turning. It didn't get much better even after a few turns, then it suddenly quit turning at all

We're going to take the head off hopefully tomorrow to take a look. Any advice would be much appreciated- me and the guys helping don't know a whole lot about two strokes.

Also, I'm looking for carb rebuild kits, and can't find anything at all.. Is there maybe a carb or kit from another model that would work instead?

[rbates9]

Are you saying that the engine will not kick over with the kick starter? If so will the kick starter move when you kick it or is it stuck also. Have you had the bike running at all? If so when? If the kick starter will not turn the engine over you may want to remove the right side cover and see if the crank will turn with the clutch disassembled or removed. Two strokes are pretty simple so it will just be a matter of finding where the resistance is coming from.

For the carb, typically you don't need a "rebuild kit" but just some cleaner and maybe some new jets. If you get it apart and the o rings or gaskets are shot then you can order what you need from a OEM parts place or a web site like jets r us.

[cokecan500]

It seemed like everything was locket up. The only thing that would move was the kick lever until it got to the point where it was supposed to start engage the engine. I have never had the bike running- the guy I bought it from said he was riding it any everything was solid until the kick lever broke and he let it sit for a while. (Been borrowing my friends kx 125 lever to see if my bike would crank until mine gets in Thursday).

I'll remember that though, and look through the whole system looking for where the resistance is. We went straight to cylinder trouble though because we tried push starting a couple days ago and the rear wheel would just lock up after popping it into second gear (and dropping the clutch? Not sure now). I think it may have turned the engine once or twice the whole time we tried that.

D'oh, don't know why just getting OEM whatever I need lol- definitely going to need a new gasket, and we'll see what else- the floats weren't moving as freely as I would have thought after cleaning. There was a lot of white buildup inside I couldn't get rid of too..

Thanks for the help, it seems every time I visit and read a random thread I think to myself "dang, glad I read that.. That'll save me a lot of time or money in the future"

[rbates9]

I would start by seeing if the crank will turn by it self. Then see if the transmission will turn by it self and go from there.

[cokecan500]

Ok, well we decided to take the head off out of curiosity and see what the cylinder and piston looked like.
It looks like I'm definitely going to need a new piston, and the cylinder is probably going to need some work too

There was water everywhere (Not sure if this is normal), including the exhaust pipe (I'm guessing not normal here). Also found a metal shaving under my cylinder/piston.

Pics all posted with comments on a web page I just threw together (sorry it sucks, I only put about a minutes worth of work into it).
http://bradrainosek.com/kdx200/

A couple pics for the lazy:

The cylinder- a scratch and a rough spot.


Piston- Lots of extra and missing chunks on top.


Scrape going up the side of the cylinder form the hole, and a rough edge of the top of the piston.


There's a small shaving of metal in the bottom corner in the water.


The metal up close.


My bike so far.

Also, still nothing will move- the kick starter won't rotate past where it's supposed to engage the engine, and the part that the piston connects to is also frozen.

Any advice about what to do with the piston and cylinder would be much appreciated- fix ( what by whom)? replace (what with what?)

Tomorrow I'll try and make time to go deeper and figure out what's jamming everything up..

[Julien D]

The piece of metal is probably part of a bearing cage. Big end rod bearing, perhaps. That would also explain why the bottom end is locked up. Cylinder will probably need a re-plate. Scrub it down with a green scotch brite pad and some lubrication (wd-40 or similar), and see how it looks. Bottom end will almost certainly need rebuilt as well.

[scheckaet]

bottom end splitting looks like the next step.
I'm with Juliend on that one.

[cokecan500]

I got the bottom end pulled out of the bike and sitting here on my table, but I can't help but wonder, would it not be cheaper and easier just to buy another motor before bore etc, new piston and fully rebuild the top and bottom?
Any idea off the top of your heads what motors or parts will fit my 95 200?

[rbates9]

95 and up are the same bike. If you do decide to buy a different engine then you should still expect to do a top end and replate. It may not need a replate but you should plan on it. Also you will not know what the bottom end is like. Might be good, might not.

If you want piece of mind then you should rebuild what you have. But you still need to find what is wrong with it to begin with.

[cokecan500]

Yeah I guess you got a good point there- after seeing the condition of this one and other motor rebuild projects, I don't think I could run another one without opening it up anyway..
I'll spend the rest of the night and morning gathering tools and studying and host a case splitting party tomorrow afternoon : a few of my riding buddies are surprisingly interested in this project as its the farthest any of them have been in a 2 stroke before..

Any advice on places to shop for tools like a flywheel holder, bearing puller, etc?

[scheckaet]

got all my tool at rmatv.com when I did my bottom end.

[cokecan500]

Ok, well we didn't quite get as far in as I hoped, but we at least verified what was wrong.
One of the bearings tore itself apart and apparently distributed it's pieces throughout the motor

If you look closely on the left side you can see where part of the metal is torn.


Didn't have the tools to take it down farther, but it looks like the rest of the engine wasn't in the best condition either :/


Right now I'm leaning toward just selling the bike as is and using the money to buy something that's actually sort of working.. My options are hold on to this and throw money at it till it works, or sell it and use the money to buy something that I can ride in the near future.

[rbates9]

Parting ways with it might be the right thing to do at this point. Or looking into getting a running engine for the bike. To rebuild what you have there will probably get up around $800 - $1000 depending on what else you find when the cases come apart.

[KDXGarage]

Shop on craigslist to see what KDX's are going for in your area. Around here, you can get a decent runner for $1,000. You never know what you are getting, but you know for certain you need a lot on the one you have.

They don't run forever, and this kind of maintenance is required if allowed to run until it breaks.