After - USD Front Forks

First photo: 1998 YZ250 front forks mounted up to a 81' 430XC frame.
Second photo: Same as above.
Third photo: Same as above.
Fourth photo: Same as above but, notice stock Husky stem and stem nut.
Fifth photo: Stock Husky rubber tipped steering stop will hit the YZ lower triple clamp just above the center line of the lower clamp. Plenty of clearance btwn tank and forks at full lock. Notice welded up and redrilled tank mount. I could stick the tip of my pinkie finger through the tank mount hole on both sides - extremely wallowed out. The tank bolt was worse - trash bin - I mean recycle bin. The upper portion of the bushing pressed into the lower triple clamp can also be seen. 28 years of hard and neglected living. Street legal motard conversion in progress.

Great experiment and thanks for sharing it with us. I think I understand the stock steering stem worked in the Yamaha triple clamp? Are the length of the Yamaha forks close to the same as the stock XC forks? It looks like the stock steering stops also worked. Keep us posted on your progress.
Mike

Very nice! I had a spare KTM front end lying around and found that it was also a bolt-on to my 81 430 XC. It's rough right now... just in 'trial assembly' stage.

Hey Picklito- is that a set of 45 or 50 Marzocchis? I've got a cherry set of 50s and was thinking they'd bolt right on but wanted to check the current measurements for trail & offset before I switch- no need to make it turn worse than it already does. Have you measured yours against stock & if so what are the measurements?

The ones in the photo are WP 40mm USD's from a 93 KTM 550. It turns out I've got way more KTM stuff than Husky stuff lying around. So, I've also tried a set of '91 WP's and some 45mm 'zokes. By far the cleanest swap of those 3 is the 91 parts. Back then KTM used frame mounted steering stops (just like Husky) and the 91 clamps fall perfectly onto the stock husky frame stops. Done. No further mods needed. The 93 WP's and the 'zokes both have steering stop bolts right on the bottom triple clamp which need to be removed (just unscrew the bolts), but then the husky frame stops end up using the allen head bolts as their mate. Not quite as nice looking, looks a little more 'swapped'. The 91 stuff looks like it was designed to be there, without any grinding or modifying. And you get rubber mounted bars, which I like.

I have not measured trail or offset during any of the trial assemblies, as I don't really have an accurate way to do it. The only 'measurement' I did was to reference the fully bottomed position of the suspension. All these forks run right at 300mm travel, so at least the wheel runs over the same range. I mean, we wouldn't want to make the bike more of a chopper by bolting on a longer fork (and this swap doesn't) and we wouldn't want the wheel bottoming into the fender (and we're good here too).

Sweet, thanks. I just got my FoxForx back together and mounted, will take some measurements and post, then maybe try my 50mm 'zokes for comparison.

This is a little off the subject of USD forks...has anyone tried a Honda 43mm conventional catridge fork (88-89) and triples on a Husky? It seems this would be a great modification if it would work. Race Tech makes a lot of parts for the cartridge fork and you can get rubber mounted CR500 clamps. It sounds like the 91 KTM forks and triples might be a great alternative to the conventional husky fork and drum brake. What model KTM (MX, XC, EXC) would be best to use? It would sure be nice to use a pair of the 50mm conventional forks I had on my 1998 380EXC.
Mike

Ya, the 50mm WP conventional fork would be awesome for many reasons: It's a bolt on. It keeps the "conventional" look which is a little more vintage. It's a nice riding fork.

A couple downsides that I can think of: Unless you buy a fancy aftermarket bar clamp, you're stuck with the stock bar position since the bar mounts are cast into the top triple (same problem with the 45mm 'zokes) and that's not quite the right riding position for this bike (too far forward IMO), they're less common (think 98-99 KTM), they have a great reputation, so guys 'in the know' are always looking for them. That means a few more $$$ usually. And they're a bit heavy.

Hey Schimmelaw,
Your swap is lookin' sa-WEET!!

And LCLK,
I think you owe us some pictures... Fox Forx are made of GOLD these days. You need to show 'em...

Absolutely! And they'd look great with the gold rims.

Update - Upside Down Forks

Update on forks.

I love clean and shiney parts.

Photo 1: Triples powdered satin black w/ stainless allens - in honor of. Note removal of original cast in YZ fork stops on lower clamp. Forks rebuilt w/ bushings, seals and oil. Springs good. Powdered cable guide. Rubber bushed number plate mounting. Fender hardware shown. Upper carbon fork protector (got borrowed from another bike).

Photo 2: Business end looking down. Hopefully, never from this close. Pressure relief valves.

Photos 3 & 4: Views. Original lower guards. Looking at some carbon ones but $75.00 plus. Number plate for fun.

98' YZ250 forks are readily available, will support an EBC 320mm s/m rotor, were cheap ($100.00 for the WHOLE front end) and maintance/rebuild parts are available. A great platform for the motard required 17" rim and bad assk rotor/relocator bracket.

Street legal motard conversion in progress.

Great post and thanks for the update. Very nice looking conversion to a modern fork. I am wondering if earlier YZ forks will also work using the stock husky stem and bearings? The 82-83 YZ forks were great forks and Race Tech makes a gold valve or emulator for this fork. I believe the overall measurement of the 83 YZ fork, from the axle center to the top, is about an inch shorter than my husky forks (36 vs 37). Besides, you can get a fairly strong DLS front brake that will have a gold rim. Does anyone know if this will work? Mike

Mike,

I don't think you will find an answer to your question here. The only way to know if it would be a "close" swap is to know the OD of the Yamaha stem at the top and bottom. With those measurements you can check with your bearing guy and see if he has a bearing/race set that fits the Husky steering head tube and the Yamaha stem. If a steering head bearing is available w/ the proper inside and outside diameters - the hard part is done. Any steering stem length issue can be dealt w/ via a bushing/spacer on the bottom triple clamp.

This was exactly the delima I dealt with. No bearing available for the Husky steering tube and stock YZ steering stem. Tube too small and stem too thick. Modifications required. I thought my original plan of USD forks, big rotor & 17" rim - was for not. Met a couple of machinist who fixed me right up.

What I'm trying to say is ....... anything can be made to fit - but it may take a little engineering and some outside help......... Buy the forks/brake setup you want and get after it. It is doable, just don't take no for an answer.

Rick

Hi Picklito,

Just wondered if you had got any further with fitting these forks and if you had any more pics to post?

Oh... and did you use the KTM wheel or did the Husky one fit?

Pics of Forks and Yokes

Hi Picklito,

Here's a couple of pics of the yokes and forks.

KR

Stu

The bike works fine, but no more pics right now. I used an entire KTM front end: triples, forks, wheel, brake system. It's a bolt on that way.

Hey Picklito,

So whats the final word on the fork swap?

Did you end up with a complete 91 KTM front end?

Did the KTM stem fit the Husky bearings and races?

And how different is the KTM set up vs the stock Husky?

hey Schimmelaw,
So did the 1998 YZ250 forks bolt right up to the 81 husky frame?

Highdez,
Not a direct bolt on. Bunch of work. Stock Husky stem to small for the Yamaha clamps. Stock husky stem pressed into lower YZ clamp w a bushing cut to take up the difference. (Yamaha stem much bigger/thicker). Upper Yamaha triple has a bushing also. Once Husky stem got set up in the Yamaha triples - stock steering bearings and races were used.

schimmelaw,
You have inspired me to attempt to connect some Yamaha forks to my 82 XC. I have a set of 99-00 YZ clamps - do you think your machinist would be able to fabricate another set of conversion bushings if I sent him my YZ clamps and Husky stem/bearings assembly?
Gary