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I'm sure this has been done but I don't know how well it was documented so I thought I would add to the many different combinations of known to fork swaps. I realize this thread is worthless without pics and I will have some up in the next few days.

I read a lot of different threads on making the conversion and I decided that this would probably be the cheapest way to do it.

The highlight are KLX300 Triples, 95 KX250 Forks, Stock 99 KDX Rim/hub, stock 99 KDX Brake, Custom Machined Clamps for KDX Axel.

All of the details are below.

I bought a set of 99 KLX300 Triple Trees with good bearings on eBay for $30 including shipping. These are a direct swap on my 99 KDX200. There are no fitment issues. On my stock Triples I was running eBay special 1" risers similar to these from Moose http://www.mooseracing.com/products/?pr ... tId=114626 and a Scotts Steering Damper. In order to run the damper with the risers I had to purchase an extended pin for the damper part Number 28 (http://www.scottsonline.com/Stabilizer_Parts.php.

The risers and damper all fit perfectly on the KLX Triple. I had installed new steering bearings recently on the stock triple and tested for smoothness on the KLX triples with the stock race and KLX bearings and everything was nice and smooth otherwise I probably would recommend going with new bearings and races. So to recap I'm using stock KDX races and Stock KLX300 bearings. The races may be the same for both bikes but I'm not positive about that.

I found on planetklx that Brewster had swapped 93-95 KX250 Forks straight onto his 2001 or so KLX and it was a straight swapwith the use of machined axel spacers. So I purchased a set of 95 KX250 Forks on eBay for $68 including shipping. I already knew that Slick_Nick had done the full KLX300 swap and was able to use his stock front wheel and axel with no problems. Knowing this it became apparent that with the use of brewster's machined clamps http://www.planetklx.org/techtips/kx-to ... kswap.html that I would be able to run 95 KX250 forks in klx300 triples with my stock brake, wheel, and axel.

I got in touch with Brewster on both the PlanetKLX and Thumpertalk sites and he agreed to make me a couple of his axel clamps $40 http://www.planetklx.org/techtips/kx-to ... rkswap.pdf so I would be able to use my stock front rim. The reason I went this route instead of doing a complete KX front end swap with RBDesigns KDX to KX Stem Swap http://www.rb-designs.com/rb_designs_llc_027.htm was because my bike came with Black Excel rims and I didn't want to have to either find a black KX rim or swap the hub to that of a KX. So this was the best option for me.

I will post some pics of the completed bike as soon as I get the forks rebuilt which I should complete tonight. I'm also waiting on the clamps to come in from Brewster which they should be here in the next day or two.

I'm planning on revalving the KX forks to better suit trail riding as well as installing the appropriate springs for my 180# weight. The KX forks came with what I believe to be .40kg springs installed. They were rebuilt at some point by Pro Circuit and had a sticker on the side stating .40kg. I contacted Pro Circuit to find out more info on the rebuild and they did not have any information available for me. I'm going to ride it first with the .40 springs and see what I think. If I buy stiffer springs I will probably purchase KLX330 springs. With the use of KLX springs and spacers it will bring the front ride height back down to what the Stock KDX was. I have the Forks slid up in the triples right now in order to bring the height down. This is possible because I'm using the 1" bar risers.

One other thing to mention and I haven't verified that this is going to work yet but it has worked for other. I've ordered 2005 RM250 fork guard sliders which have a brake line mounting tab similar to the stock KDX mounting position. This will hopefully allow me to run what I believe is an upgraded stock KDX brake line. I think it is the exact same size as stock and if I can remember to measure it I will braided brake line that came on my bike when I purchased it. The routing will be the same as stock as well. Test fitting without the sliders in place makes it seem as though they are going to work out just fine.

good job

just for clarification, to shorten travel, you are not talking about spacers on top of the fork springs, are you?

Good question and I definitely didn't explain it well.

Adding a spacer above the spring would only increase the preload. I would need to use the shorter KLX spring and a spacer on bottom end of the damper rod which would limit the extension of the rod in effect shortening the total fork length. I hope that makes sense. If you look at this http://www.planetklx.org/techtips/kx-to ... kswap.html it explains it better than I did.

OK, I was hoping that is how you did it. Making it hit the top-out spring is the way to go.

I'm almost done rebuilding the forks and I should have the RM fork guards in today but I wanted to post this update on the shim stacks that came in the 95 KX250 forks. I do not believe them to be stock because the peening had already been removed and there were Pro Circuit stickers with settings on the forks when I received them. So here is the shim stack that came in the forks.

Base Valve
Nut
Valve Cap
Spring and Space
22 x 11.22 x 0.4mm (ID OD Thickness)
11 x 7.95 x 0.25
Piston
22 x 7.91 x 0.11 x4
20 x 7.91 x 0.1
16 x 0.1
14 x 0.1
11 x 0.1
22 x 0.15
18 x 8.47 x 0.5
Base

Mid Valve
Nut
19.88 x 1.6
11 x 0.2
14 x 0.1
17 x 0.1
18 x 0.1
20 x 0.1
16 x 0.1
21 x 0.1 x2
Piston
22 x 0.1 x5
14 x 11.2 x 0.4 x3
22 x 11.4 x 0.4
Spring Spacer
12 x 7.95 x 0.14
Valve Cap

I'm posting this for my reference and possible for future suggested shim modifications. My plan is to ride the bike this weekend with this shim stack, .40 springs, 10W fork oil, 100mm, Start with clickers in the middle setting (~10). I will see how the bike responds and hopefully post results. I'm in a bit of a pickle as probably most are because I don't really know what to look for as far as how a good suspension should respond. So I'll probably use this thread to track my results. Any and all comments will be greatly appreciated.

Why 10 weight oil?

Stock midvalve only had about 4 shims, as best I remember from working on a set back in 2007????

On first sitting on the bike and working the forks up and down they seem extremely stiff. It could be the oil and it could be that they are binding. I ran out of time last night and intend to look up the proper install procedure for the 95 KX forks.

I just went with 10 weight oil because that all my local shop had. I don't think this is the stock shim stack.

Anyway here are pictures from the install.





Its hard to see the spacer but it is there around the kdx axle and behind the kx fork clamps


Here is the brake side clamp. Basically the stock axle screws into the brake side spacer and clamps into the kx fork clamp.


Here is a pic of the 1" bar risers and the Scotts steering damper extended rod.


And finally a blurry side profile shot.

So I got a chance to ride the new forks this past weekend. I have to say at first I definitely did not like the feeling of the bike. I think I had the front end set too hard and the back end way to soft. The conditions were slick and the first 30 minutes of riding it felt like the back end was on ice. I finally laid it down really good and decided to soften up the front end which helped a little. I rode for another 30 minutes or so and decided to stiffen up the rear shock. This seemed to help quite a bit with the loose rear feeling. I'm not sure really how to describe it except it constantly felt like the back end was out running the front end of the bike. Some of this could possible be due to the fact that my tires are terrible and need replacing very badly. All in all right now it still needs some tweaking as I didn't feel comfortable on the bike this weekend.

I assume the race sag is set given your knowledge of suspension so I would have to think the rear tire and not having the front dialed in is the main culprit. I would put new tires on before I went adjusting too much. Had to be a bit anti climatic, which is a bummer but you will get it dialed soon no doubt.


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So I totally rebuilt the forks with new seals, bushings, and 5 wt fork oil. They still feel extremely stiff to me. I'm not positive that the springs are the .40 rate springs. The reason I think they are is because the outside of the forks have a sticker that is barely legible that I think says .40. I weigh 180 and am a slower trail only rider. So I think the .40 spring rate would work for me. I would probably be better suited with .42 but as I said the still seem very stiff at .4 with the compression and rebound at full soft. It may be that the rear shock needs rebuilt but as I've never really messed with it. Is there anyway to verify that the springs are .40. Below is a picture showing the only markings that I could find on the springs themselves. I also tried to rig up a broom handle with some weights on it to see if I could test the springs for the spring rate and either I wasn't successful in accurately measuring correctly or I'm way off in my calculations or the outside of the forks are marked wrong. I calculated that it takes 30 # to compress the spring 1 inch which should put the spring rate at .53 which I find hard to believe. A quarter inch mis-measurement would result in the rate dropping down to .42. Which I did do it by myself and could have measured a little inaccurately but .25" is a lot to inaccurately measure. Anyway here is the pic. Hopefully someone may help me determine what the spring rate is.



Also I rearranged the shim stack on the base valve. I'm trying to soften it up some more. The new stack is

Base Valve
Nut
Valve Cap
Checkvalve
Piston
22 x 0.1 (OD x Thickness) mm
20 x 0.1
16 x 0.1
14 x 0.1
11 x 0.1
18 x 8.47 x 0.5
Base

When measuring with a broom stick, I found that the 1" - 2" and 2" - 3" measurements were where consistency was found.

The four marks DO mean the rate, but I am not sure what the numbers are.

So I checked out the rear shock and discovered that I basically had no control over the compression regardless of the compression clicker settings. Rebound was being controlled fairly well as on changing from hard to soft and vice- versa slowed down and sped up the rebound. So I got the shock apart dumped all the old oil out bled off all of the unknown amount of nitrogen. Got everything apart. I have a replacement all balls seal head kit. But I would like to replace what I think is called the piston band/bushing. I'm attaching a picture to make sure that I'm calling it the correct thing and to ask where to order a replacement.

Also does anyone make any changes to the shim stack on the stock kdx shock to better suit a kx fork conversion?

Don't forget the o-ring under the band.

Whenever you get around to ordering a piston band and o-ring, let me know what prices you are seeing. I once sold a KYB made kit for 1989+ KDX shocks. I am thinking of compiling the parts to offer such a kit again.

Thanks.

That's part of the problem. I'm not sure where to order the band and oring from. For example on racetech's website they sell and shock shaft bushing. I'm not positive that this is the piston band and if it is how would I know if it comes with the oring? Can you suggest a place to order the band and oring? Thank you.

The shaft bushing goes inside the seal head.



Call Race Tech and ask them, as they may have the parts, just not on their site.

"So I checked out the rear shock and discovered that I basically had no control over the compression regardless of the compression clicker settings."

How long has it been since the shock oil was changed? Back when I was working on suspension, most people with fresh oil thought it was so much better.

If you can see a faint line around the piston band in the middle, then it is definitely time for a new piston band and o-ring. The ring actually squares off as it wears. It is weird to see when you take it off.

I am going to sell the kit again probably next week. I have a few parts on the way to combine with ones I already have. I see KX and YZ KYB kits, but no KDX kits.

So do you think that I need to replace the piston band? I have absolutely no idea when the oil was last replaced. I've had the bike for a couple of years and never really noticed the lack of control. The change to the kx front end has made it totally obvious that something was up with the back end. It sounds to me like I need to put everything back together with the new seal refill it with oil have it charged and hopefully I will see a significant improvement.

Is there any recommended shim stack mod for the stock shock for woods or is it about as good as it's going to get?

It is when the fresh oil and charge are done that the change is noticed.

I would change the piston band, but it is up to you, I guess. It is not easy to get it on without doing a side cut.

What thickness are the 8?? larger shims on the compression side? Thinner ones may help.

If KarlP is on here still, I revalved his like that 10 years ago. He really liked it, as well as his A class friend.

this may be a stupid question, but I believe my KDX forks have a tab that stops the odometer gear from rotating. assuming the KX forks don't have this, do you find that the odometer gear moves around?