Complete KX500 top-end rebuild instruction here!

[John]

OK.

I have been working with this together with Doordie and the current release is 1.0 (which is work in progress). The instruction will give you some good ideas what to do when you are rebuilding your KX500 top-end. Some of the tips are generic and will work for other two-strokers as well.

Since the format of the information is better displayed in HTML (web page) I have decided to create a web page, see below. Comments are welcome. Bare in mind that this is this first version and it will be updated once I have my cylinder back from the workshop that is re-plating it next week (so I hope anyway).

The goal here is not to create a fancy web page. Personally, function always goes before design...

http://www.hallbergs.net/kx500/

Should you think anything is wrong or you disagree, please comment in this forum so both Doordie and I can answer these. I can subsequently update the web page with all useful information.

I think this information (once agreed being correct) can be added into the forum when Paul is back.

//John

[musturbo]

Thanks John &Doordie!  This will be a major help.

[P_Fio]

That was really considerate of you guys to do that.  Thanks.  

[John]

No feedback on this? I was expecting at least some comments...

//John

[demographic]

This is very good stuff  Thanks for putting the time and effort into it.

I have posted a link to it on one of the Visordown threads as there are a few on there with KX500s

About the only thing that I spotted that seemed strange was that instead of saying Removal (for the cylinder that is) you say "Dismounting".

Not really a problem at all  then..

I liked the fact that you came up with a good fix for worn powervalve pins cos mine are worn just like the ones in the picture

I have stored the webpage into my favorites.

Good work, very helpfull indeed.

Regards Scott

[John]

Scott,

Thanks (and on the behalf of Doordie as well). Have added your feedback and some other stuff as well. There will be a more complete update once I get my cylinder back from the re-plating. Then again, I will probably be out riding and not have any time for this...

The power valve fix amongst other things are Doodies work, I merely documented it whilst doing it on my machine.

The whole idea behind this is to assist others who also shares the KX500 passion. All this information exists on the Internet (and some does not) but is rather scattered. The goal is to have a complete rebuild instruction including tweaks. I rather be beaten by a KX5 than any other machine. So it's in my own interest to see that they all work fine!

I don't know what these mods will do to my machine other than making it better. I probably can expect some additional HP, but not much. Maybe Doordie has an idea?

//John

[gowen]

John, excellent write up! Very detailed and easy to read. The pictures are great too.

[demographic]

Scott,

Thanks (and on the behalf of Doordie as well). Have added your feedback and some other stuff as well. There will be a more complete update once I get my cylinder back from the re-plating. Then again, I will probably be out riding and not have any time for this...

The power valve fix amongst other things are Doodies work, I merely documented it whilst doing it on my machine.

I will be sorting out the powervalve when I next do some work on it so should be able to provide better feedback then, I have just had a quick look at the page so far and untill I have the cylinder in my hands it's hard to tell how much will be relevant to me.






















Might be getting the files out though

Regards Scott

[KXcam22]

John & Doordie,
  That is excellent!  I really like the photos.  As a suggestion for some additions, It might be helpfull to have a section on cylinder surface prep, a torque chart for the top end nuts and bolts, a guide on how to assemble the KIPPS so the opening time is correct.  The big end rod radial clearance (rather large) answered lots of my questions.  I recently took my crank in to have a new rod put in since I could get mine to "clink" up and down. My past rule of thumb was that any perceptible movement meant it was shot. The Kawi dealer laughed and sent me home.  Now I see why.  Good work guys. Cam.

[John]

Thanks,

This will be more complete once I get my cylinder back. I will then get the last pieces together (with the help of Doordie).

Question; is the format OK or should I add the pictures into the page (togther with the text). I am thinking about also zipping it up so people can download it so you do not have to be online all the time. I will add reference-ID's for each picture and reference the pictures in the text, ie. see picture 3.

Any ideas?

I will contact Paul once he is back and see how this information can be migrated into the forum (should he want to). I do not want the resposibility of maintaining this for ever...


//John

[KXcam22]

John,
  The format looks great.  I would suggest I might be handy to embed the photos and convert it to a .pdf.  The main advantage of this is that you can save and print the whole thing off in one document.  I am doing my top end right now so I eagerly await and details and tidbits. The piston chamfer idea is really good. Never done that before and my new Wiseco is sharp as a razor. I also noticed one other port area on my barrel that needs attension.  Inside the main transfers at the base gasket area, exhaust side, inside of where the nut goes on outside to bolt the barrel down. Mine ('92) has a bulge inside to give thickness to the outside transfer wall but this directs the flow away from the transfer wall.  I had to carve a bit away to make the outter port wall smooth. Thanks. Cam.

[demographic]

John,
 I would suggest I might be handy to embed the photos and convert it to a .pdf.  The main advantage of this is that you can save and print the whole thing off in one document.

That's a very good idea.

I have been trying to get together a collection of PDF bike manuals for a while now so having some KX info on file would be most usefull.

[doordie]

Hi Folks!

I will remind you about the squishclearance.
You can search for it here in forum and found out why it´s  so importent.
As a rule: NOT below 1.3 mm, and you can chim off the head or buy
different thickness of headgasket.Only check what compression you have
when mods done ,so you not use wrong gasoline oktantype.
John asked about how much power this mods in barell will do and with right squishclearance, I will say 10% overall power and no "pinging".

//doordie

[John]

OK, got my cylinder back and the (Doordie / John) instruction is complete. Check out http://www.hallbergs.net/kx500/

I hope this is useful information, it has been for me. Unfortunately, I have made too mane modifications at the same time to be able to tell which one made the biggest difference. The end result is that my engine performs REALLY well!

FYI. I will be zipping it all up for offline access. I have not decided the format yet.

Feedback and questions are welcome, use the Pitbull forum or the email address on the web page.

The reason why I have made the effort to document this is; because I can, not because I am a particularly skilled two stroke mechanic and actually know what I am doing. Doordie on the other hand knows a lot about tuning two strokers and the KX5 in particular.

Good luck with your own rebuild!

//John

[John]

OK.

The squish can easily and accuratly be meassured with solder. A couple of people have told me this but it did not work for me. The reason it didn't work is that the solder I have is 0.2 mm in diameter. It does work if you use the really thick solder (petrol stations quality) - not the proffesional stuff for surface mounted PLC circuits. It all made sense to me when I went to the local car repair shop and noticed the solder thay use (>2mm).

You guys who have given me feedback about this - sorry for being so thick.

//John