complete engine rebuild

Discussion specific to the 1995 - 2006 KDX200 (H Series) and 1995 - 2005 KDX220R (A Series) models sold in the USA
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commanderjjones
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complete engine rebuild

Post by commanderjjones »

You may have seen a couple of other posts about my engine issues. I've decided to just tear it completely down (split the cases) and do a complete rebuild.

So I have a few questions............

(1) Does anyone make a COMPLETE (including ALL bearings, seals, etc...) rebuild kit, or am I going to have to tear it apart to evaluate what I need? I'm sure that most of the tranny bearings are probably fine, but I'd just as soon replace EVERYTHING while I'm in there. I see that Wiseco makes complete kits for most of the MX's, but I didn't see one listed for the KDX. It sure would be nice to just drop in a new crank and not go through the hassle of pressing the old one apart. Although I have a press and am fairly skilled, I have concerns about that part, since I've never did it before.

(2) Although the cylinder walls look good and are within spec', the crosshatching is completely gone. Should I go ahead and send the cylinder off to be re-plated?

(3) Other than a flywheel puller (which I'll buy) and a press (which I already have), will I need any other specialty tools?
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Re: complete engine rebuild

Post by david »

Breaking the crank apart and replacing the rod is not something you try just because you have a press. That's one you leave to the pros as you need a jig and the proper tools to align the two halves.

The factory plated cylinders don't show a cross hatch. As long as the plating is in good shape and there is no scoring or flaking, you just replace piston/rings. You only need to re-plate if it's damaged.

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bufftester
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Re: complete engine rebuild

Post by bufftester »

(1) Have not seen a complete KDX bearing/seal/gasket kit. You would need to source them separately.
(2) As david said, inspect for scratches, worn spots, flaking (especially around the ports)
(3) All above plus case splitter, impact wrench (makes getting the clutch bolt off super easy) flywheel holder (of course I am a tool hoe...)
commanderjjones
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Re: complete engine rebuild

Post by commanderjjones »

bufftester wrote:(1) Have not seen a complete KDX bearing/seal/gasket kit. You would need to source them separately.
(2) As david said, inspect for scratches, worn spots, flaking (especially around the ports)
(3) All above plus case splitter, impact wrench (makes getting the clutch bolt off super easy) flywheel holder (of course I am a tool hoe...)
A case splitter? I've never seen such a thing. Gonna have to Google that one. I've always just tapped them apart carefully.
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Re: complete engine rebuild

Post by Tedh98 »

commanderjjones wrote: I've always just tapped them apart carefully.
Only do that if you want to throw your crank out of wack or bend a shift fork shaft.

I still get suprised at how loud the pop can be when the cases finally split with the proper tool.
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Re: complete engine rebuild

Post by Tyl3r »

sounds like everything that you need has been mentioned above.

Since the cylinder walls don't look to have any cross hatching, I would vote for a replate. The new plating they use today greatly outlasts the old plating that Kawi was using way back when.

I sent a crank off to Millenium tech when I sent them my cylinder. They rebuilt and balanced for me, I was wayy to nervous to try to take that one on myself. Might be an option if you think you need a rebuild.
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Re: complete engine rebuild

Post by SmokingGreen »

Tyl3r wrote:sounds like everything that you need has been mentioned above.

Since the cylinder walls don't look to have any cross hatching, I would vote for a replate. The new plating they use today greatly outlasts the old plating that Kawi was using way back when.

I sent a crank off to Millenium tech when I sent them my cylinder. They rebuilt and balanced for me, I was wayy to nervous to try to take that one on myself. Might be an option if you think you need a rebuild.
What would be the best replating option for a cylinder that needs to be done?
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Re: complete engine rebuild

Post by SS109 »

SmokingGreen wrote:
Tyl3r wrote:sounds like everything that you need has been mentioned above.

Since the cylinder walls don't look to have any cross hatching, I would vote for a replate. The new plating they use today greatly outlasts the old plating that Kawi was using way back when.

I sent a crank off to Millenium tech when I sent them my cylinder. They rebuilt and balanced for me, I was wayy to nervous to try to take that one on myself. Might be an option if you think you need a rebuild.
What would be the best replating option for a cylinder that needs to be done?
I prefer Millennium but Langcourt and Power Seal also do good work. Avoid US Chrome due to their poor attitude.
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complete engine rebuild

Post by KDXGarage »

commanderjjones wrote:You may have seen a couple of other posts about my engine issues. I've decided to just tear it completely down (split the cases) and do a complete rebuild.

So I have a few questions............

(1) Does anyone make a COMPLETE (including ALL bearings, seals, etc...) rebuild kit, or am I going to have to tear it apart to evaluate what I need? I'm sure that most of the tranny bearings are probably fine, but I'd just as soon replace EVERYTHING while I'm in there. I see that Wiseco makes complete kits for most of the MX's, but I didn't see one listed for the KDX. It sure would be nice to just drop in a new crank and not go through the hassle of pressing the old one apart. Although I have a press and am fairly skilled, I have concerns about that part, since I've never did it before.

(2) Although the cylinder walls look good and are within spec', the crosshatching is completely gone. Should I go ahead and send the cylinder off to be re-plated?

(3) Other than a flywheel puller (which I'll buy) and a press (which I already have), will I need any other specialty tools?
1. No. There is no such kit for any USA KDX. There is no aftermarket crankshaft for any USA KDX. Connecting rod kits are available for some models from the aftermarket.

You might get the crank apart, but you may want to leave the disassembly and reassembly to a pro. It requires special tooling beyond JUST a press.

2. OEM Electrofusion plating does not have the aftermarket or typical crosshatching that many speak of. I posted a pic elsewhere of one of two new cylinders I owned. There is a little maybe, but nothing like most people assume and think it is "ALL GONE". It never was there to start with.

Buy, rent or borrow a crankcase splitter. If you had looked in the service manual, you would have seen and been aware of such a tool (You do have one, right) :oops: :oops: :oops:
Thank you for participating on kdxrider.net. :bravo:
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Tyl3r
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Re: complete engine rebuild

Post by Tyl3r »

SS109 wrote:
SmokingGreen wrote:
Tyl3r wrote:sounds like everything that you need has been mentioned above.

Since the cylinder walls don't look to have any cross hatching, I would vote for a replate. The new plating they use today greatly outlasts the old plating that Kawi was using way back when.

I sent a crank off to Millenium tech when I sent them my cylinder. They rebuilt and balanced for me, I was wayy to nervous to try to take that one on myself. Might be an option if you think you need a rebuild.
What would be the best replating option for a cylinder that needs to be done?
I prefer Millennium but Langcourt and Power Seal also do good work. Avoid US Chrome due to their poor attitude.
I agreed. Nikasil plating is what you are looking for. I only have experience with PowerSeal and Millennium. Both places are top notch, no complaints from either!
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