Siezed?

[greencannon]

Man this situation is sure turning out to be a nightmare for you. Sounds like the guy you purchased from should have no business owning a dirtbike, poor bike....
 There is a plastic gear in the clutch case that actuates an arm which controls the powervalve arm. It spins a unit that moves back and fourth by centrifugal force with ball bearings and a spring. It adjusts according to the speed of the gear turning it and the engine rpms.  Im wondering what is happening there while its trying to move but the powervalves are not....id look close for any kind of wear or damage and make sure there is proper operation there on that end.
That thing must have been running like a weak 250 at best,  considering it's condition

[littlewing78]

No, he shouldn't have a bike.  He has a KDX right now and I am pretty sure it has been sitting outside all winter uncovered.  I did see that lever that is meant to move the power valves.  The thought did cross my mind that something must be going on inside if its not allowed to move when it should.  Maybe since it is controlled by centrifugal force everything will be ok.  No real solid connections.  I will look into that when I open it up.  The bike did have pretty good power but surely not what it should. I don't have much to compare it to. The only other bike I have ridden is that guys KDX and my KX blows it away.  I got the bike for $750 so putting a little more into isn't breaking me yet.

[Goat]

Ebay is your friend. When I completely rebuilt mine I looked all over the place for parts and found out 98% of the time ebay was the cheapest. If you do your homework you can fix everything as it were new for a decent price. I think mine ended up costing $1100 total to completely rebuild the engine. I did have to buy a new used cylinder and case halves so knock $370 off the total. Only thing that I didn't mess with was the rod/lower bearing & trans internals. All bearings, seals, gaskets, piston and rings were changed. I even got some parts from Sandblaster (OEM Cycle)

[littlewing78]

E-bay does have some awesome deals.  I just got a nearly brand new seat for $35 shipped.  Rocky Mountains prices for new stuff still seem to be better.

So I played around with the motor a bit tonight.  Mostly just looking for obvious damage.  Aside from the piston I cant find anything else broken.  I checked the water pump and it's fine.  I think the seal is bad because my oil comes out milky when I change it.  But wouldn't I be getting oil in my coolant?  There are no sign of any at all in the water pump.  I pulled the clutch plates to see if there is any obvious damage to those but I don't see anything.  What should I look for with clutch plates?  With it all together, I pulled the clutch lever and all seems fine.  I can see the pressure plate releasing while I pull it. So no problem there.  I don't have a big enough socket to remove the baskets so that's as far as I got.  I am pretty certain that I need a new seal at the output shaft.  When I lay the engine on that side I get oil leaking out.  So Is it possible that my bike would act like it did with bad rings?  I am just hoping that's the only major problem.

[1989kawasaki]

often ebay has unbelievable deals on bike parts  i bought a reed cage, front fender, brake caliper , hose and master cylinder all for $1 each

[greencannon]

Measure thickness of clutch plates both friction and the metal ones. Im sure one of the Guru's here have the spec.  If its stock setup they are pretty tough and long lasting, but knowing the bikes maintenence history they could be worn causing weaker performance.  A good indicator of  "time to replace it"  wear is a little lip forming on the  smooth flat surface of the metal plates and pressure plate. Check for grooves in between the basket fingers, minor ones aren't bad but deeper ones will cause clutch plates to stick (becareful not to slice your finger in there its usualy sharp ! )
 Countershaft seal is easy to replace, dont forget to check the o-ring behind the collar on the shaft.
 Kawasaki.com has parts diagrams you can use for parts reference while working on it. just click on owner info

[littlewing78]

Got the case split open.  Found a little surprise when I took the rotor off.  There was a one inch long end of a screw driver stuck to the inside of the dish.  My guess is that somebody tried to pry the rotor off and broke the  screwdriver.   I flushed everything out real good with oil and cleaned it up.  Everything inside looks to be in good shape.  I cleaned up the rest of the bike too and started putting it back together.  Now I just need to start ordering some parts and bring the beast back to life.

[littlewing78]

I got a complete Gasket set and a full set of oil seals for the bike.  I think I need to have my cylinder re-plated or sleeved.  I have been doing some research on both.  Seems that re-plating is the best option but sleeving is cheaper.  Any suggestions on those?  When I put my cases back together what is the best gasket maker to use?  I have a tube of high temp RTV.  Will that work?  Thanks

[1989kawasaki]

yeah get plating. i heard sleeves slow you down because of the friction between the iron

[Goat]

I recommend plating. It will last way longer and will run/cool better. IMO sleeves are junk in 2 strokes.

I prefer Hondabond to seal my cases. Never had a problem with it in 16 years that I've been rebuilding engines. It costs a little more but I would rather use the right tool for the job than have to tear down again just to re-do a sealing problem.

[littlewing78]

Thanks goat.

[sandblaster]

I agree with the plating.
It is more money but it has better longevity and some argue better performance.
I thought that cylinder looked a bit haggard 

[greencannon]

Plating all the way, have a reputable shop replate if you do then you can forget about it. Sleeves are old technology and require good craftsmanship when installing ( hard to find these days )
 I have run many pistons thru my Maxpower plated cylinder with no honing or boring or any fuss. still looks like new, a clean tightly sealed air filter works wonders.....prob the #1 most neglected maintenance procedure in dirtbiking. Prob the #1 reason for most top end failures.
Glad u decided to rebuild, the chassis looks to be a good motivator for that.

[DoldGuy]

Plating all the way, have a reputable shop replate if you do then you can forget about it. Sleeves are old technology and require good craftsmanship when installing ( hard to find these days )
 I have run many pistons thru my Maxpower plated cylinder with no honing or boring or any fuss. still looks like new, a clean tightly sealed air filter works wonders.....prob the #1 most neglected maintenance procedure in dirtbiking. Prob the #1 reason for most top end failures.
Glad u decided to rebuild, the chassis looks to be a good motivator for that.

As Greencannon stated a "Reputable" plater, I have a cylinder that was replated & has less than 4 hours run time with issues. Sent the cylinder back to the plater to offer the opportunity to "Make it Right" & with their reply I will not be using them again, & yes it was Maxpower. I have a cylinder that was plated by Rick Peterson over a decade ago & still looks great, so if the job is done right the first time you will have a product that will last a long time. I know that over time Companies can go from a first class business to a P.O.S. & the reverse can be true also, but with the $330 bad experience that I have had with Maxpower, I feel it is in the interest of KXRider members to know & have seen multiple cylinders done recently from this plater that NEVER should have left their shop! Spoke with US Chrome about their policy, and they would take care of the problem, I cant say they would or would not but another member here said they "Have" stood by their work in the past.
Okay enough stone throwing by myself, I just dont want anyone to follow my experience 
DoldGuy

[greencannon]

Hey Dold, sorry to hear about your bad experience with Maxpower. The work I had done with them was some 8+ yrs ago.  I have to say the workmanship and customer service was excellent at the time. In fact my cylinder is still looking great and still in spec. Even many pistons later.
You know whats Ironic ? I first used Maxpower due to a similar bad experience with US Chrome. and I was curious about their ceramic technology
You know whats even more ironic ?  Rick Petersons and MaxPower merged to form one company quite a few years ago.

Maybe the merger was a bad thing for the company....maybe you just got a "lemon" cylinder job and a "lemon" for customer service...
Maybe the companies are now buying their materials from cheaper suppliers because of economy, causing poor quality issues. We have all seen that from various industries lately.
Oh well, Im not bashing anyone here. Littlewing78, we just hope you your rebuild goes smoothly.be wise in your choices during rebuild.