New kdx220r top end inspection

[tystick82]

So its been a few weeks since I picked up this 220. I've been looking around the site for advice on what I should start with as far as maintenance.

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So tonight I finally got around to start taking the top end off. The piston is definitely toast. Scores on the exhaust side. I'm not sure but I'm thinking by the looks of everything this motor has never been apart. Maybe some of you guys can give me a little advice on the rebuild I'm starting into.

How can I tell if this is the stock piston? What is a good way to figure out the cylinder needs to be replated?

This is my first rebuild on my own. I did a few as a teenager with my dad but all I really did was put parts together.

So when I took off the exhaust I found this. The copper exhaust gasket has a piece missing. And the piston skirt on the exhaust side is definitely scored. I've only popped the head off not the cylinder yet..... Maybe tomorrow I can get more apart. I'm not positive until I get everything cleaned up but possibly need a replate on the cylinder. Any advice would be appreciated and thanks in advance.

[tystick82]

Few more pictures

[KDXGarage]

The flakes and chips should be an area to clean and inspect thoroughly.

[tystick82]

I think most of that is the white crusty stuff on the head studs. Looks like some kind of oxidation. Overall its doesn't appear to gummed up with oil and sludge tho. Hopefully tonight I can get the cylinder off and see what the kips looks like

[KDXGarage]

The port edges is where I was talking about.

It's a stock piston, probably WAY past time for a new one.

[bufftester]

Yeah, the edges of the intake ports need to be inspected closely.

[tystick82]

Just finished up taking off the cylinder. I'm happy I didn't run the bike at all..but have a bit of work ahead.

Piston is toasted

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I'm definitely sending the cylinder out to be plated. Can now clearly see scoring all around and some dings

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After seeing the missing piece I'm gonna keep moving forward and take the motor out so I can split the case and see how much the bottom end is damaged.

[bufftester]

Hey, look an OEM 220 piston...

[tystick82]

Yes sir and thanks to everyone here I opened up the motor before it got any worse. I hada few local people who ride with me tell me "don't worry just ride it" glad I didn't listen

[KDXGarage]

Good job on taking it down. I would suggest rebuilding the crankshaft (connecting rod kit or parts) as well as the main bearings and seals.


It's an 18-year old stock piston. At some point, it is not the "stock pistons are bad", but "having an 18 year old piston is bad".

[doakley]

Go get a good manual if you don’t already have one. I like cyclepedia. Then read thru the tear down clearly. It isn’t as difficult as you might think.

[KDXGarage]

Yes! A service manual is the best money one can spend on a bike.

[tystick82]

Service manual was the first thing I got for it a few weeks ago. Just ordered a hour meter so I can more easily keep track of maintenance intervals. Got all the parts off the head and hopefully be able to send it out Friday.

[pumpguy]

Man, you're lucky. If that OEM 220 piston had gone to pieces, you'd a pretty much wrecked the whole engine. Be sure you use a forged, (Wiseco) piston. Don't go back with OEM.

[tystick82]

I ordered a Wisconsin piston and full gasket kit last night.

[KDXGarage]

stupid phones!

Add "Wiseco" to the dictionary. :-)

[tystick82]

I'm wondering is this an electrofusion coating or nikasil? I've been searching around and sounds like Kawasaki switched at some point in 2003 but wondering the difference. I stopped at the local shop and the owner wanted to just ball hone the cylinder and lightly dremel the chips.

[bufftester]

I'm wondering is this an electrofusion coating or nikasil? I've been searching around and sounds like Kawasaki switched at some point in 2003 but wondering the difference. I stopped at the local shop and the owner wanted to just ball hone the cylinder and lightly dremel the chips.

Nicasil is the material, electrofusion is the process

Either way never hone it...the plating is very thin (like 0.001 thin) and honing will expose any damaged areas and make it worse. Once it chips it's done.

[KDXGarage]

Electrofusion is Kawasaki's proprietary coating name. Nikasil is a name brand from another company. The 2003 change was not on the KDX's.

DO NOT BORE OR HONE an Electrofusion cylinder (manual says so)

DO NOT run a ball hone. If you think you have port edge chips now... !!

Here's a pic of the inside of my new 2005 KX250 engine's cylinder wall. Below that is a couple of pics from a new KDX175 cylinder I used to own. There is no cross-hatching on Electrofusion that gets worn off. I have a new 1989 - 1994 KDX200 cylinder in the "lime green hoard" that is smooth-walled also.

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[tystick82]

Ok so I skipped over the mechanic who wanted to hone my cylinder and just sent it out to be replated. Talked to my friends at the machine shop and sounds like no big deal doing crank so that should be out in the next few days.

Has anyone read the break in process in Kawasaki manual? Recommends tearing down after an hour or so to smooth piston and cylinder with 400 or 600 grit Emery cloth. Wondering what's everyone's thoughts on this?