Kx-D project update 2

[ebeck]

This is a KX125 frame/KDX200 enginne/KX250 suspension project.

Ignore the dirty motor. I am having it totally rebuilt and will clean it and paint it at that time.

The swingarm and rear motor mount lines up now. The swing arm was cut and the rear mout was milled 2mm larger to accomidate the KX swingarm pin.

For reference, the steel sleeve in the engine case that makes up the rear motor mount is not a solid sleeve. It is aproximatly .75 inches. In between the two sleeves is empty space. If you mill the case 9mm each side, you will loose most of the actual mount strength.

Another thing, the swing arm bearing is about an inch long. Cutting 9mm off of each swing arm on the inside does nothng but remove empty space. The only load bearing surface if the swingarm bearing and that is untouched as shown below. What is removed is just filler. Beteen the bearing and the inside seal is just air. A much better option in my opinion i to remove the matrial that has no load. Additionally, the KDX has a swing arm mounting diamater of the newly cut KX swingarm. The CAD image is courtsy of TT member Bucket.:applause:

I had a machine shop do the work with a mill. It is dead nuts accurate.

The head stay lines up just fine. I removed the front motor mounts as you can see and I have a mock up. I'll cut them and tack them then weld them. Look at the bottom motor mount though, Doh! It does not line up. Apparently the 99 frame lines up. the 2000-2002 frame does not.

The bottom motor mount is actually a double layer mount so that will be tougher to reproduce. More griding too. Dang...

After the mounts are welded I will blast the powder coat off and blow a new coat of paint on the bike using OEM colors. The I'll bolt it all up. Somewhere in there the motor will be getting a full on rebuild. The enture suspension has already been fully disassembled inspected and rebuilt. It is better than new. I even blew on a new coat of Plum Crazy thermal paint on the rear shock spring.

 

[ebeck]

You can see my test paint and ignor the dirty boot. I'll clean it all up and strip and paint the frame rebuild and paint the motor. Bottom line ignore the dirt and bare meal on the frame. It is in progress.

I have been avoiding the airbox for fear of the work. I bought a 2000 KX250 airbox and a KDX200 air box. I figured I'd use the KX250 box and make a plate and mount the KDX200 boot to it to fit the KX250 airbox to the KDX200 motor. I thought what a shame as the KX250 intake boot is WAY larger than the KDX200 boot. The reduced restriction and WIDE open KX250 airbox seemed like a great mod the the KDX200.

Well I bolted up the KX250 airbox and boot to assess it and guess what, it fits like a glove. :applause:

 

[ebeck]

This is the first mock up to check for clearance and any other unanticipated issues.

I can lower the motor just a tad more by grinding the cases. Pretty clear where the bottom mount neds to go.

Pipe fits suprisingly good. Aftermarket pipe can be bent pretty easily to fine tune. I got this from **** for $12. It is basicly just a template. I ned to fab up some mounts for the pipe.

 

[ebeck]

A KX/KDX hybrid is alot easier than people make it sound. I say this becasue I use information that is out there already so there were no real suprises. TT member Bucket was the first to do this I think. He provide alot of the information for me.

I'll put together a complete how to when it is over in one post. Really on a scale of 1 to 10 is is about a 4. I do not work with my hands for a living by thee way. I bought a new angle grinder yesterday and this was the first time I ever used an angle grinder. I have usewd dremel's before but this is my first time working with metal.:applause:

My advice have a machine shopp modify the swingarm and rear motor mount in the engin case. It cost about $230 but it is dead nuts accurate. No slop what so ever. It likley fits better than stock. The cuts are at thousandths precision such as 9.345 mm.

Anyhow, here are the remaining issus and how they were solved.

The fuel tank needs to be modified to fit the cooling tower. I find that an industrial heat gun abd a pipe with elbow work superbly.

Here is what it looks like when done.

Here it is installed and with clearance. the tank fits like a glove now.

 

[ebeck]

The KX250 shock works as well with the 01 swingarm and the revised 02 linkage. It fits but well see once I get it down if there is interference issues. Fingers crossed. It looks plumb crazy.;)

Notice the rear head stay. It has been cut off.

Here it is with the tank installed. No clearance problems. I have to clean up the casting with some sand paper from my material removal process. Do they make metal sand paper?

That is it. All the major assemblies fit. All that is left is to weld on the motor mounts paint and reassemble. All of the fabrication is over basicly save the welding. The motor looks right at home in there huh?

 

[ebeck]

I'll do some final mount shaping and then the frame gets sand blasted and then painted next weekend. You can see my test paint there.

The motor is being completly rebuilt as we speak.

Suspension is already completly rebuilt.

Really all that is left is working out the exhaust and final assembly.:applause:

 

[kingsxjt]

Looking Good! :cool:

 

[pete fry]

This is going to help me alot,great pics.Is it a KDX pipe your using in that pic?

 

[2 strokes for life]

Keep up the great work. Those welds you have are awsome for someone who dose not work with metal to offten.

 

[Canadian Dave]

Looking good ebeck. Keep the updates coming.

David

 

[ebeck]

I had a machine shop do the welding. That was too important for me to do it.

Ok I painted the frame and it turned out like ass. The PJ1 paints are awsome and the finish is incredible. However there is too much dust in the air. I am going to have the frame powercoatd dark grey like they did in 03.

Real shame too becasue I really like the old school Green. *&^%$#@

 

[2 strokes for life]

Ok I painted the frame and it turned out like ass. The PJ1 paints are awsome and the finish is incredible. However there is too much dust in the air. I am going to have the frame powercoatd dark grey like they did in 03.

Real shame too becasue I really like the old school Green. *&^%$#@

Why dont you rent a painting both.

 

[thebleakness]

Keep up the great work. Those welds you have are awsome for someone who dose not work with metal to offten.

I was thinking exactly the same thing! It's funny how being a welder that is one of the first things I notice on something fabricated. :bang: :coocoo:

You were talking about sandpaper designed for metal, you want to find some emery cloth for the ruff stuff and then crocus cloth to finely sand it down smooth.

Your doing an awesome job, keep it up. I'm really looking forward to the end result. How much are you looking at paying for the total conversion if you dont mind me asking...

 

[2 strokes for life]

thebleakness, i am no great welder but i gust started 2 weeks ago in my grade 9 metals class. Do you weld for a living.

 

[ebeck]

Well the cost is alot. The parts were about 3K total. Then I rebuilt the entire motor top and bottom, rebuilt the suspension soup to nuts, put all new bearings and bushings in the suspension whether they were needed or not, bought new bars and applied clamps, new tires, new Talon front wheel to match my gold and silver rear(ouch), new exhaust, new graphics, new reeeds, new new new. It is basicly a new bike.

It is alot like spending $2500 on a nics KX and then spending 2K freshening it up.

I could have slapped on the used parts as is and been done for about 3K. As it sits I am over $5K. But you'll see it will basicly be new complette with armor alled tires and seat before the first ride.

 

[2 strokes for life]

ebeck, at least it will be fun to ride and in the end thats all that matters, ridding.

 

[thebleakness]

That's quite abit of money involved, at least it has matching hubs and rims! :) Once again, I'm looking forward to the final KX-D. :cool:

thebleakness, i am no great welder but i gust started 2 weeks ago in my grade 9 metals class. Do you weld for a living.

I started welding also in 9th grade and I've had at least 1 welding/machining class every semester for the next 3 years. I do odd fabrication jobs for extra money but I havent had to do welding for a living (I still got 9 weeks till I graduate :nener: ) but I was offered a part time job as welder, still thinking about that one...

Does your school/class participate in SkillsUSA? If so, DO IT! Competiting in welding is awesome, it really tests your abilities. Last year I got 4th at my Regional comp and I managed to pull a 1st place this year. :boss: Next is state for me, 70 contestants all welding at once, I shall see if I can beat my last year placing of 10th. :bang:

 

[adam728]

Make any progress on the silencer fitting? I'm kind of interested in how that will line up for you.

 

[ebeck]

Not yet Adam, I am waiting for the motor to come back. I am taking the frame to be powdercoated today. I hope to see next week.

Hows that incredible YZ?

 

[ebeck]

I did the project not to save money but to cross another thing on the list of things to do in my life time. Build a bike.

 

[adam728]

I only got about 10 minutes on it Sunday morning on the way back to Tucson. It has tons of power, but seems pretty controlable. I could lug it down in 4th as low and the Rekluse would let it go, and it would pull from there up with no problems. Throttle response feels crisp, but not so on/off instant that it will be a death rocket when I get tired (which takes about 15 minutes for me, at most).

Sunday morning I'm going to spend a good amount of time setting everything up for me (sag, bars, levers, clickers, etc) and spend a few hours out playing around on some single track north of town. A guy from Tempe I work with is supposed to come out and ride the KDX, he want's to buy a bike, but isn't sure if he's ready to drop that much $$$ on a toy. I'll probably post a report sometime after that on TT, I'll be killing time in airports on my way to work in Mississippi this week.

 

[thebleakness]

Adam, did you buy Aaron's yz? If so..holy crap! That thing looked awesome and was a really good deal as well. I would have thought about it if I had the $$ for it.

I'm thinking about buying a new (to me) bike, I'm looking at a woodsified KX250. I would like to keep the KDX for friends (and father) who don't own bikes but enjoy riding but at the same time getting a more capable bike would be nice. Do you think you're going to have regrets about selling the KDX?

 

[adam728]

Yup, Aaron's YZ it is. I feel bad because he called me to go riding this afternoon (he was in Tucson), but I had to work and really didn't want to blow any vacation days. :(

I'll probably miss the KDX when it's gone. It's an awesome bike for what it's made for, playing around in tight/technical stuff. I just grew tired of the thing that can't be changed, the ergonomics. Fat seat, big ramp up to the tank, etc.

I'm better going to one bike now anyway. My girl moved out from Michigan finally, so I am probably going to get her a little bike to play with, and I really don't have room for everything.

 

[ebeck]

I picked up the Rebuilt motor today. Top and bottom ennd is all fresh. New Gold and silver Talon wheels are ready. Frame gets back from Powder coater next Tuesday.