600 d-xc

So I bought this 1990 bike for $400 on craigslist. It does run but only if pull started.

Below is the pics.

This is the bike after a good cleaning.




Then I tore it down to nothing. What I found was ALOT of loose bolts. hardly no grease an oil line which was electric taped. Hard to see but heres a pic.


Then I found a hole in the frame.


Got the hole welded up.


I also know the float is sticking in the carb (prob my starting problem) so I will start the project there while sanding and painting the frame and the rear shock is at Race Day being rebuilt.


Well today I got a few things done.

Got the frame to bare metal then repainted (Black)

Got the swingarm all tore apart degreased and put back together.

Got the carb torn apart and cleaned again. Was alot of trash in it AGAIN.

Found a small problem with a O-ring I will have to replace.

Put a few things back on the frame Coil , swingarm,footpegs

Cleaned all bolt holes with a tap and all bolts got ran through a die.

Here is a little peek.



And the carb




Feel free to comment on any of it.

Hope this is interesting to more than just me


I'm following this....that is beautiful. Looking forward to seeing how she turns out.:excuseme:

I had a perverse lust for those things when they were new, so will follow your build with interest....sweet :excuseme:

Looking good. What I find is so interesting how the basic concept and layout of your bike is similar to my 00 400sxc.

Well I got a little more done to it on Sat the 28th.

Got the valves adjusted on the motor (the right way) :cheers: the first time I did it I used .01 inch :banghead: not .015 MM . Then I took the time to scrape the crud off the engine and get it all clean and pretty.Well as pretty as a 19 year old engine could be. I'll get pics later the wife had the camera.

Then I started on some of the small parts. The rear breaks system is now clean and pretty on the outside and all flushed out (3 times to get clean fluid)

and is working as good as new.

I had a piece of aluminum plate so I made a skid plate it turned out great and will really protect the frame and engine. I know the added weight will be worth the protection from large mtn rocks I plan to ride.and it looks cool too.

As said before I will get pics in a little while it's kinda cool outside:smirk:

I have also been talking to the wife about the engine going to Race Day to have the top end done. So it wont go in for a little while.

So far Race Day will do :

Rear Shock rebuild $85 + parts if needed

Front Forks reseal $85 + parts (about $150 total)

Top End $200 + parts (about $350 total)

This would put me at $950 for the entire bike and rebuild not counting my time.(which aint worth much anyway):worthy:

So what do you think? Should I just do the top end myself doing a hone and re-ring or pay someone to do it.It would be about $150 for me to do it and I could save $200.

Now on to Race Day Performance. They are located in Denver ,Co Great people to deal with and a Very quick turn around time on rebuilds and revalves. Once they are done and your bike is up and running they will meet you at a track called Thunder Valley (also in Colorado) and get your suspention set up for you free of charge!! If you cant get to the track for their help they will do it over the phone with you at no charge. I have used them for shocks and forks in the past and most of my local shops send their stuff there also. Just look up the name on any search engine and they will pop up. (I know quit blowing them up lol)

I will be returning to work today (sunday the 29th) so my progress on this project will slow down untill my next trip home (Dec 22nd to Jan 2nd) I do come home most weekends but try to spend that time with the wife and my 4 year old. Enjoy the post and let me know what you think about the motor work being done. I WANT YOUR INPUT.


Wow, you've been really busy....great progress in such a short time! Re the motor....I did top end myself on my 96 620EXC and it was really pretty simple - when dismantling, I marked the link on the timing chain that needed to line up with the mark on the cam sprocket, and kept it tied up tight so that it stayed in place on the crank and didn't drop down into the case. This way I could put timing back spot on with no faffing. Rings were dead easy to change. I cleaned a small amount of carbon off the inside of the head using oven cleaner. Also, while it was apart I flushed through the waterways as there was a fair bit of crud floating around. I was surprised how easy and how quick it was to do the whole lot. If I were you, I'd do it myself...it's a good learning experience and very satisfying when done!

Yeah I had a week off for the turkey eating contest which Im sad to say i think i lost. Anyway about all I did for 3 or 4 days was work on that thing.

I'm leaning in the diy top end. I've built a few motors and have the know how it's just a time frame thing. I think if I get the parts I can do it in Dec. when I get back home.Should only take a few hours.

I didnt get any pics today because I had to leave for work. I did however manage to post in the intake/jetting section about doing the carb. so we will see how that turns out. Will also drop off the the rear shock this week if I'm not on the line till 6:00pm every night.

great bike mate keep it orignal nice to see one so cleen

Thanks KTM 620. It is a great bike so far. A little more work and $$$ and it should be better than new. It will be a while before I can get back to work on it though. My job is killing me and being cold here all week it's kind of hard to work in the shop.

I'm also having trouble talking the wife into letting me build the motor on the kitchen table :banghead: But I'm working on her :cheers:

Thanks KTM 620. It is a great bike so far. A little more work and $$$ and it should be better than new. It will be a while before I can get back to work on it though. My job is killing me and being cold here all week it's kind of hard to work in the shop.

I'm also having trouble talking the wife into letting me build the motor on the kitchen table :banghead: But I'm working on her :worthy:

Ahhh, the kitchen table always goes down a treat! I had it covered in bits of brake calipers and brake fluid last week, and I got some lovely smiles and comments :cheers: The other half popped out for half an hour on Wednesday and I took the opportunity to borrow a stainless steel kitchen pan and a nail brush to help with cleaning my chain. Chain looks good. The pan scrubbed up ok, and the nail brush wasn't too bad after I'd rinsed it through with some petrol. If only she knew.....

Well if she wont come around on me using the table. I will just load it in the truck and take it to work with me. I stay in my toy hauler camper while at work I'll just build it in here.:banghead:

Any update on you bike? how is the finished product?

Good old craigs list ..I got me one as-well just this weekend $500 though :) Starting from cold is a bit of a carry on kick 6-10 times with decomp pulled in then turn engine just past TDC ,one big old kick and she's away im going to check the tappets and float hight tonight .....Mines got 600MX on the front of the frame but comes with all the enduro gear ?? 18 rear wheel and so on ..Did KTM just put the enduro gear on to the MX bike or do you think its a HOME brew ?????? ill post some pics....

I have a 91 600 D/XC that im getting ready to do a top end on. I just love those old KATOOMS!!! Im just gonna make it a field bike for now since my 07 525 E/XC is my woods ride.

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