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I've been having some engine issues on my '02 KDX220 and it made a loud squeal before I shut it down the other day, so 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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I will be watching this thread closely because I want to overhaul my 97' 220. I hope you get a lot of help from everyone here and please update this thread with as much detail as you can. It will be a great help to me. I'm a total noob to working on dirt bikes.

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Figure on crank bearings and seals. If the barrel is worn, a replate, fresh piston and rings. Service the power valve. Start your plan with this. Anything else will have to be decided on as you take it apart. Trans issues, water pump, ect.

Check the crank big end, if it is questionable, get a new crank (often cheaper than trying to rebuild your existing one). HotRods or OEM.

Finally, before you do anything, figure out worse case what the parts will cost and what the value of your bike is. You will not recoup the price of the rebuild when you sell it, if you do. If you plan to ride it forever, then the rebuild may be worth the money as you'll have a 'like new' engine that you will get the pleasure from.

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15 hours ago, rehammer81 said:

I will be watching this thread closely because I want to overhaul my 97' 220. I hope you get a lot of help from everyone here and please update this thread with as much detail as you can. It will be a great help to me. I'm a total noob to working on dirt bikes.

Will do.

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16 hours ago, William1 said:

Figure on crank bearings and seals. If the barrel is worn, a replate, fresh piston and rings. Service the power valve. Start your plan with this. Anything else will have to be decided on as you take it apart. Trans issues, water pump, ect.

Check the crank big end, if it is questionable, get a new crank (often cheaper than trying to rebuild your existing one). HotRods or OEM.

Finally, before you do anything, figure out worse case what the parts will cost and what the value of your bike is. You will not recoup the price of the rebuild when you sell it, if you do. If you plan to ride it forever, then the rebuild may be worth the money as you'll have a 'like new' engine that you will get the pleasure from.

I've already had the top end apart, cleaned the KIPS, and replaced the water pump. That was right before the loud squeal. This time I'm gonna tear it completely down (bottom end) so I don't have to go through this again anytime soon. I've heard a blown head gasket make a squeal once, but my compression is still good, so I assume it's not just a head gasket.

I was wanting to just put a new crank in it, but can't seem to find one for the KDX. It's easy to find one for the MX'ers, but apparently the enduros are a different breed. I'm just gonna order a crank kit (new rod, bearings, and pin) from Hot Rods and have the press work done by a local specialist down the road from my shop. From what I've seen and priced so far, $100 for the kit and $60 for the press work will be about the same cost as a new crank.

Assuming whatever that squeal was hasn't damaged the cylinder (it was fine when I did the top end last week) and I don't have to have it re-plated or sleeved, it looks like I'll have under $500 in a total rebuild.......and I don't plan on selling it anytime in the near future. The KDX is a near perfect woods bike for me.

Edited by commanderjjones
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It is very time consuming to rebuild the motor as seen here:

http://www.kdxrider.net/forums/viewtopic.php?f=77&t=12241

I did the top and bottom end on my 02 KDX 200 and it is very satisfying to ride a fresh motor you rebuilt yourself.

Maybe you don't need to do the bottom end. The only reason I did mine is because of up and down play on the crank that made a rattly sound and damaged the cylinder. I don't think a worn crank will make a squealing sound, more likely water pump. If your crank is good, I would leave it and not risk damaging the engine by making a mistake during rebuild. I made mistakes but learned from them and now feel confident in rebuilding 2 strokes.

If you have any up and down play, I would go ahead and rebuild crank. I did a top end and noticed a little play and the next time it got bad.

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I would tear it down and evaluate what parts need replacement. Then order everything OEM. If crank is stock, have it rebuilt. If cylinder is worn, have it replated. Here is a video that will help you, even though it's for a KX. I have a tool list on my site.

 

 

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11 hours ago, slowmoto said:

It is very time consuming to rebuild the motor as seen here:

http://www.kdxrider.net/forums/viewtopic.php?f=77&t=12241

Great tutorial. I've rebuilt several, so I feel fairly confident in my ability to do it. Just making sure there weren't any hidden pitfalls to avoid on the KDX.

I've got everything on order and plan to start the tear down process tonight. I'm just gonna play it safe and do a complete rebuild.....crank and all. I don't like to do things twice. Having a completely fresh engine for less than $400 is peace of mind, since we ride some VERY remote locations.

Edited by commanderjjones

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