1993 yz250 forks

[Julien D]

Well, I got a 93 yz250 front end for free. I have everything but the caliper. The 94 KDX caliper I have bolts up fine. Forks are in good shape, not leaky. Looks like they have been rebuilt recently.

The only oddity was the strange top triple. The hole for the stem was huge, and used a threaded sleeve over the steering stem to secure the top triple. I picked up a 95 upper triple for cheap on fleabay as it's more similar to the KDX's. I will need a small bushing/spacer around the top of the stem. Looks like the KDX stem will press into the lower triple just fine.

Probably not much of an upgrade from my 94 USD's, but at least I will pick up rebound adjustment and a larger diameter fork.

[80elkster]

Hey are the fork outside diameters in the tripple clamps the same?
My friend has a 90 yz250wr and the forks are nearly the same as my 93 kdx. you may be able to fit them right into your existing tripple clamp and only have to adust axle spacer lengths. On thing they have over the 93 94 forks is the rebound adjuster. I have Gold valves in mine and I use Mobile 1 ATF for fluid which is 7.5 wt. I'm happy with them at the moment.

You might want to measure the upper fork diameters on both bikes its worth a shot. Let me know what you find out

[Julien D]

My buddy has an 89 yz250, and his forks would fit my triples. They went to a larger diameter fork in 92 though, so 92+ requires swapping the triples. I'm not sure what the actual size is. The 93-94 kdx are 43mm, right? Looks like 89-91 yz250 are also 43mm. Not sure what size the 93's yz250 forks I have are, but they are bigger.

So no, they don't fit my triples. Close, but not quite.

You're using the yz250 forks?

[80elkster]

No I still have the original USD forks but have new springs and Gold valves. The forks off the earlier YZ are the same diameter at the triple clamps. I'm not sure what the lower dia is. I believe the stock forks are 41mm, not sure would have to check.
Good luck with the YZ forks and post your results

[Julien D]

Ah yes. 41mm sounds right, so the early yz forks must be 41mm as well, and these are 43mm. Looks good on paper anyway.

I haven't gotten round to taking the stem and lower triple by the machine shop yet. The KDX stem is larger diameter where it goes into the lower clamp, so I'll need to have some machine work done on the lower triple itself to get the KDX stem pressed in. Some sort of sleeve or busing in the top triple will be needed as well. I think it will be not too bad.

I'll post back with some results in a week or so....

[Julien D]

Almost done. Got the forks on, caliper mounted up, and the brakes bled. I ended up having to use the YZ caliper. The KDX caliper seemed the same, but the mounting bracket spacing was off. You could easily make a mounting bracket to use the KDX caliper though. We had the YZ caliper sitting here (my buddy was planning on keeping it, till I talked him out of it) so I just threw it on. Takes the same pads as the KDX caliper. The YZ lower triple had to be bored a bit to accept the KDX stem, and the retards at the machine shop down the road charged me $65 to do it exactly the opposite of what I told them to do. It's kinda jacked up, but I think it's good enough for now. I have another KDX stem so I can have another go at pressing the stem in the correct way if everything else works out well.

I'm gonna wrap it up in the morning and have a bit of a test run. I'll post some pics tomorrow evening if all goes well ;).

[Julien D]

Rode a few hours yesterday. Nothing heavy, but I tried to push it as hard as I could around the fields out at moms place. Got out in the woods at a buddy's place too after we stitched it up. He's got a decent hill climb, some big rocks, and some really tight woods we goof off in. I really don't have words to describe the difference. I know my old forks were jacked up, but damn. It's a totally different bike. Spring rates feel great to me, and the low speed damping is excellent. I'll have to see how it does on the hard hits when we go down to brushy in a couple weeks.

Crappy cellphone pics, wife has lost my camera again. I need to replace some plastics. KX500 black rear fender is on the way. I'm holding out on shrouds as long as I can. I have better things to spend the money on. My bikes not half as nice as most the guys (and gals) here, but I'm really proud of the work I've put into resurrecting it, and even more proud of the fact that it never lets me down. Such an awesome machine!!


I did verify they are 43mm KYB's. Don't know too much else about them at this point, except they seem to work quite well.






steering stop, seems to work fine...



I got the top triple out of a set of triples with a bad stem on fleabay. It looks aftermarket, but I can't find any identifying marks on it. Any ideas? And yeah, the bars are bent. I had one pretty hard get off up in WV. No major damage or injury other the bent bars and a few bruises. New bars are in the garage...