Splittin the cases!!!

[beefking]

Recently the intake side piston skirt shattered, and there are still a bunch of small pieces stuck down in the crank cavity. So far I have gotten the cylinder off, tranny out, right cover off and guts out, magneto pulled, and the case bolts out.
Question is, what is the PROPER way to actually split the cases? I can get the seams to open up a little bit (had to torch the seams a bit) but I cant seem to get it all to come apart at once. I think one of my problems is with the crank area. I can't get the top and bottom parts of the cases to spread apart equally...I can tell because the crank won't rotate at all when i start to spread this area.

Please, any tips are very much appreciated!!!! :)

 

[kx_693]

i hae split cases the wrong way with screw drivers, and u have to pry all the way around easaly, but this is not recomended the case is so oft that it nicks all up....i would recomend if u plan on ridding for a along time or racing to invet in a motion pro cae splitter its a tool that works so well i thought i was dreaming. we ave had the case apart on my brothers125's about 4 times this sesion between the 2 bikes, and never had a problem, once we got this tool

 

[IrishEKU]

If you used heat to split them......wrong answer. Y ou shouldn't need to. The cases are held with a machined and micro thin film or seal that is in place from the factory......I have no idea as to why you would need heat to do this othter than if there was an exisitng problem.(Read: someone has done it before)

 

[beefking]

Maybe it wasn't necesary to heat the seam but it seemed to work...it was also cold out ok! :)

Where can I get one of these case splitters and for how much? Would the dealer have one maybe? I don't plan on splitting the cases any time soon after this time (i'm replacing rod, seals, main bearings, etc. as well).

 

[beefking]

Forgot to mention its an 89. ;)

 

[jamin326]

go to www.motionpro.com and look under the tools section, they aren't cheap tho

 

[canyncarvr]

EG has some tips on splitting cases on his site:

http://ericgorr.com/techarticles/2techlowrebuild.htm

I'd consider splitting a case with a torch and screwdriver as soon as I'd end-gap rings with a vise and a file. I'm sure it's not an uncommon occurrence.

Sugg. retail on the motion pro piece: $141.60. Much cheaper than a case 1/2, countershaft......pick-a-piece!

http://www.motionpro.com/servicetools.html


BTW...this is a 220? With the known issue of pistons that go to pieces? In which case you are NOT putting in an OEM (Pro-x) piston back in?

 

[beefking]

Nah its not a 220. Its an 89 KDX200. We got it for free about 2 years ago; previous owner said it had recent top end, which was a lie because it still had the STOCK piston!
It lasted this long so I think i'll go with the pro-x piston as a replacement...

Well I give up, I think i'll just take it up to the local shop to have it split. I am too afraid of cracking one of the cases, just wouldn't be able to afford it.

Thanks for the help guys. :)

 

[jdbrusch]

I think the main problem you are having is with the fit between the cases, crank and bearings,they are all known as a press fit.You maybe able to find a puller(or pusher in this case) at the local auto parts dealer or even at a tool rental store.The design of the puller is what is known as a harmonic or steering wheel puller,it has a threaded hole at the center and 2 or 3 slots that originate from the center and are 3 to 4 inches long.You will have to buy long bolts that will fit into either the magneto screw holes or the cover holes,depending on which of the holes line up with the slots in the puller.
You then install the puller,threading the long bolts into the case as for as possible and thread the center bolt against the end of the crank.You tighten up the center bolt and give it a tap with a hammer, the tap may not be needed if the crank starts to move right away,it may creek and grone as the crank moves out of the case.you can heat the case around the bearing with a heat gun and this may help.I made one up a few years ago from just a 1/2" steel plate with a theaded hole in the center and 3 holes that match up with the cover screw holes and it works well,you do not have to be exact with the outer 3 holes just drill them oversize eg. 1/2" and use large fender washers under the bolt heads.This all sounds much harder the it is and once you see the tool and how it is designed to work it is easy to do.The manual may have a picture of the puller(pusher) in the section on bottom end this may give you a idea of the tool .
James.. :thumb:

 

[mrmodine]

I agree...splitting the cases on the KDX is a tough task.  I too had to to it on a friends 96 and it was a real chore.  As mentioned above, they are a press fitting and they are extremely tight.

We tried to get the tool from local shops and they didn't have it...we then called the local Kaw shop to see if they could do it for us, surprise surprise, they said they just use heat and hammer!!  Fantastic!  Sorry guys, we won't be using your shop again...eVER!

So, we did it ourselves and basically built our own spacer tool to back it off.  It was a chore but it worked out.  We used wood blocks so we wouldn't hurt anything (wood being soft) and still we bent two of the bolts which we had to get replaced later.

I would agree, buy the tool and maybe you can rent it out to other members!!

 

[canyncarvr]

Related, but not directly:

Get the Pro-x piston for the 200. Not to insult your intelligence or knowledge, but DO at the very least get the correct alpha designation for your engine.

If you order a piston from a kawi dealer, you have NO say as to what tolerance mark you get. It will probably be a 'B'. Why mess with unspecificity? (maybe I just made that word up...;) )

Both the cylinder and the head are marked with an alpha character: A,B,C,D..that I've seen, and Pro-X additionally makes an E&F plus a couple of even LARGER sizes.

From their website: http://www.pro-x.com/eng/default.htm

..attached is a chart showing piston choices for the '89 200


I say 'at the very least' because the correct way to do it is to measure the cylinder and get the piston to fit your needs.

Note each piston 'size' is .01mm or (rounded) .0004". There is NO sense in putting together a 200 with .003" piston to cylinder clearance if you have the choice of a better fit.

If you have a damaged coating (and it's serious enough to warrant fixing) keep in mind that a bore and replate to oem spec cost is hardly less than EG's big bore (225cc) kit. And THAT comes with a port-to-fit for your needs!!

Any bore job will require telling the machinist what sort of gas you intend on using. Part of EG's paperwork includes that question. Be sure that's a known and understood issue. Compression ratios (and thus combustion pressures) go up considerably with a bore job and the head must be machined to 'match' the fuel you are going to use.

 

[canyncarvr]

OK...I give up. The original chart cut&pasted from Pro-x didn't look good enough...and 'edit' won't let me attach so here it is.

........sheesh...this has taken WAY too much time........

 

[beefking]

Thanks for the chart, i didn't realize there were that many sizes...

Are there any online stores that carry Pro-X pistons for the KDX (89)? I called local dealer and they are saying it will cost $130 just for piston kit itselft.

I considered the 225 kit, but I don't really need more power over reliability for it. Decided to ship it off to Langcourt for a stock bore replating instead, its cheap enough and they are supposed to be very good.

 

[canyncarvr]

I've not looked at catalog vendors. Give sage a ring/call/email etc. He has Pro-X stuff. He has a link on CDave's site:

http://justkdx.dirtrider.net

Not positive, but the price you note seems to be close to what I paid for my last 'kit' from kawi.

I would hope that the figures listed by Pro-X are correct. The last piston I got from kawi was a 'B'...and it measured 2.597" (65.96mm) out of the box. While that doesn't match the chart, it's more likely a measurement error on my part. I wasn't 'looking' for .0005 at the time.

In any case, you'll need to actually measure your cylinder when you get it back. Langcourt sez you could send your new piston in WITH your cylinder so they can fit it properly. That would have worked well.

....or maybe you haven't actually sent it to them, yet?

Langcourt sells pistons and stuff, too. Howabout contacting them for a Pro-X?

 

[jdbrusch]

Always try to send in a piston when you get a cylinder plated or bored out oversize,a machinist or mechanic will final hone the cylinder to the correct clearance that the engine requires no matter which KDX200E piston you get.I would not allow him to plate or bore the cyl. without it ,I have never even heard of a shop that would even attemp this without the piston.JMHO
James..

 

[beefking]

Thanks for the tips again guys. I owe ya one-beers on me! cheers! ;)

 

[70 marlin]

bought mine from the dealer ship. cost $174 crank press & crank jig. engine laying on right side! you'll be just fine.

 

[beefking]

Well I managed to get the cases apart by making a puller out of a 2x6 block of wood. Bearing came out relatively easy actually.

Now i got all the parts I needed in and its now time to put the cases back together. Will I have to make another puller type deal with a center bolt that pulls the crank into the case? Or will it be ok to just tighten the bolts around the crank equally?
I also have the whole right case (crank and bearing) in the freezer now and i plan on heating the left case, or at least the part the bearing presses into. Maybe that will allow it to just slide in? :p

On another note...I found a pretty good deal on a +2mm Wiseco piston, so i got it. Only an additional $30 at langcourt to go up to 68mm bore!

Thanks again!

 

[rickyd]

If your ever gonna use a hammer too split cases, try too use a "soft blow" hammer, won't damage the case..
Rick

 

[cr25096er]

beef king can i see a picture of the thing u made out of wood to split the cases?

 

[canyncarvr]

I recall langcourt saying they didn't want 'assembled' cylinders. So...you took your KIPS out? Are you going to match the exhaust valve on reassy to the 2mm overbore?

Did langcourt have the piston when they did the recoat? Do they know what the piston/cylinder spec is for a wiseco? Not the same for cast/forged pistons.

And the other ports? Or, are you assuming (or know?) that a 2mm overbore doesn't effect them enough to matter?

Anyway, the manual sez (H) model, pg 7-8:
Using a suitable tool on the left crankcase to press around the hole for the crankshaft, fit the crankcase halves together with a press on the tool.

They use a jig to keep the crank at BDC during the process.

Obviously the crank should turn freely after reassy (clutch out). "If the crankshaft will not turn, probably the crank is not centered. Tap the end of the right crankshaft with a mallet to reposition it."

EG mentions a 'crack!' or snap noise that is indicative of this seating process during reassy...it's a good thing.

Good luck. Hope to see an 'all is well' post from you!

 

[beefking]

OK thanks CC, i figured i would have to use a jig of some sort.

I haven't sent out the cylinder YET, I'm still waiting for FRP to send me the piston kit, then i will ship the cylinder and piston out to Langcourt. They quoted me $180 to bore and replate, not bad i don't think. As far as matching the exhaust valve yes i believe i have (er will have) that under control!

For a jig I think a small piece of pipe with a large fender washer at the bottom and top will work, then just use the stock bolt to press it on.

Thanks for all your help!

PS: I'm hoping for an "all is well" post too! :)

 

[jpm200]

I also split the cases with a 2x4 block of wood and a steering wheel puller two days ago. Got to this thread too late. Just drilled the wood to match the bolt holes in the flywheel cover and drilled the timber to match the steering wheel puller. Used the engine mointing bolts to attach the puller to the timber and bought 3 M6x80mm bolts to attach the timber to the cases. Looked ugly but cost me AUS$10 for the puller and $3 for the bolts and worked a dream.

 

[beefking]

You didn't even need a steering wheel pully! I did the same as you as far as drilling the block to match 3 holes on the case. But, then I drilled a larger hole in the middle that lined up with the crank. There I put a M10 long bolt (i think it was m10...it was big anyhow) and a nut on the other side, with a very large fender waser (2 of them) between the nut and the wood. Once the block is bolted to the case, you hold the nut with a wrench and then tighted the bolt. The nut is stopped by the block causing the bolt to drive into the crank. Also I used a nickel held onto the crank with some tub caulk on both sides (acts like a grease) so no damage to the crank would be done. Total cost was about $5 compared to the $140 motion pro tool....