The notion of a better dual sport entered my mind in 1986, viewing Dirt Bike magazine. There was a picture of Dick Burleson’s twin cylinder 800cc Husqvarna. I had an XT350 at the time, but also had an appreciation for the smoothness of a twin from my CL125. The vision of an 800cc two stroke twin enduro bike, it got me thinking.

Soon after, also in Dirt Bike, was a small article on Peterhansel’s factory Yamaha 750cc twin Paris Dakar bike. I wanted it. I showed it to Wes, and he agreed, if we just had $100,000 and the appropriate pull with Yamaha. We were in high school at the time, and the dream sat on the back burner like most high school dreams.

In college, Wes and I rode an XT350 and XL600, respectively, as we studied engineering. We started riding longer. We started seeing how long we could ride in a day, linking together 4wd passes in Colorado, one after another for a few hundred miles at a time. Long dual sport days became a favorite past time of ours, but there was always the limitation of the bike. Not enough suspension, to slow for freeway use, and too much vibration for long highway sections, which we inevitably found ourselves on for the ride home at the end of the day. The vision of Peterhansel’s ride was still in our head.

The Honda Transalp was available in the USA about this time, 1989. We looked at it and were instantly put off by the lack of crashability, the non dirt bike ergos, and the cheap suspension and bars. Eventually the Yamaha TDM came out. I sat on one, only to find it Transalp like in its non-dirtbike feel, even worse.

Then it started growing in us. A twin-cylinder dirt bike. Something with enough power to do anything the XL600 would do, but with top notch suspension, no vibration, roomier ergonomics. And it had to be immensely durable and reliable, just like a full on enduro bike.

Again, Dirt Bike magazine influenced me. They had a bike from Extreme Cycles, a GSXR1100 motor in a XR500 frame. Two much, for sure, as the XR500 chassis couldn’t even hold up its own motor let alone a 150mph superbike motor. But it had promise, it just needed some balance, some temper, and some great suspension.

After college, we continued our dual sporting on thumpers, and I began learning TIG welding as we started conceptualizing the ultimate dual sport. I bought a Husaberg 501 in 1992. We learned a lot from this bike. The suspension, ergos, and especially two-up ability was astonishing. I met my future wife, Kelli, and two up dual sporting not only became part of my life, I learned a lot about what a dual sport should and should not be. It should be fairly long. The passenger should be positioned well in front of the rear axel, like on the Husaberg. The general ergonomics of the Husaberg were great, but the motor was the BUZZ kill of all motors, the vibration was intolerable at 50+ mph. But the power was adequate, and the suspension was excellent, even for riding two up on technical 4wd roads at 12,000 feet elevation. If it was just smooth, if the bars were 2 inches farther away, twice the gas…wider seat…less expensive parts…

I started looking at what mid-sized twin motors were available, still dreaming of Peterhansel’s Yamaha. Suzuki GS500. Yamaha TDM850. Kawasaki EX500. Honda Transalp or Hawk GT650. I called Wes one evening,

“Wes, what if we just crammed an EX500 motor in a motorcross frame, put lights and a big tank on it, and called it good? It wouldn’t be too difficult.”

“Why the EX500?”

“Well, the GS500 is air cooled, the TDM is not very popular, shifts hard, and is huge, and the GT650 is a v-twin and would be hard to shove in motorcross frame.”

“Well, nice concept, but what’s the EX500 run like?”

“The mag says 60hp. I don’t know. I’m thinking of buying one, I want a street bike anyway.”

Sure enough a week later an EX500 pops up in the paper, cheap. I bought it and rode the snot out of it. I dualsported the poor bike, even two up. The end verdict was that it was a little revvy but it seemed adequate for a DS motor, and it was very smooth. It had a great 6 speed tranny and the motor was bulletproof and cheap to maintain.

In the mean time, we learned of the Euro KLE500. I looked into it, as this was the beginning of the great world wide web. I was immediately disappointed, it was even less dirt worthy than Kawasaki’s KLR, which we considered inferior to our demands already.

We just had to cram that EX500 motor in a MX bike. The likely candidate was the Kawasaki KX500, simply because it was a fairly large bike, and it had a good reputation as a desert racer. It seemed like an easy fit. Wes bought an 87 KX500 to cut up.

We put some more time into a better prototype, around 1996 now. We worked extensively on ergonomics and compactness of the design. After studying header design, we fabricated an upswept custom 2 into 1 exhaust, with a V&H muffler from the junkyard. We stiffened up the preload on the suspension to ridiculous levels, just to see how the bike might work with better suspension. We weren’t yet ready to take the plunge and make a complete custom bike.

Until we rode it, and then everything changed.

The second prototype of the Weber KEX 500 convinced us. We were really onto something. Even in it’s crude hacked together form, it was fast, smooth, stable, and yet very manuverable. It also taught us something, which would change our approach on the project. At this time, Wes and I both had KTM dirt bikes. My KTM550 had proven itself as a very capable dual sport, both one up and two up. We looked at the KX wheels, swingarm, etc., and then looked at the KTM hardware. No comparison. The KTM was more burly in every way. The wheels, swingarm, forks, controls, everything was better, beefier, obviously meant to last. It became apparent what we needed to do. I bought a KTM 250 to cut up. In the meantime, we had done hundreds of hours of research, choosing the best components to fit together in a complete, professional way. We started finalizing our design criteria.

We wanted the Weber Rally Twin to be:

· Crashable, i.e. as durable as an enduro bike in crashes
· Smooth on the highway, as smooth as a good street bike.
· Suspended as good as a modern enduro bike.
· Comfortable, with ergonomics that were excellent for standing or sitting, on and off road.
· Equally comfortable for one up or two up riding.
· Capable of doing rough 4wd roads at a fast pace, all day long.
· Exceptionally stable in rough terrain.
· Able to cruise at 80mph for hours on end without discomfort, on dirt or pavement.
· Maintainable, with all parts available at common dealers.
· Easy to work on in the field and in the shop.
· Reliable, bulletproof, and tough.
· As light as other dual sport singles. 340lbs dry.

The Weber Rally Twin

In 1998, it started sinking in. We were going to build our own custom motorcycles. They were going to be absolutely top notch in every respect. It wasn’t going to be as easy as we thought, but our second prototype already met most of the design criteria.

We bought a press, tubing bender, mill, and lathe to compliment the TIG welder, cut-off saw and assortment of hand held power tools we already had. It was a simple but very capable fabrication shop, comfortably laid out in my 2 car garage. We purchased 4130 Chro-moly tubing, 6061 aluminum, 304L stainless header tubing, and the vast array of components needed to assemble complete motorcycles.

We began fabricating the frame jig and completing engineering calculations and CAD drawings in late 1998. For the next year and a half, we worked 30 hours a week, outside of our day jobs as engineers, to complete two Weber Rally Twins. As we progressed, we always had a sinking feeling in the back of our minds that a major manufacturer would come out with a bike meeting OUR design criteria, just as we would finish OUR bike. Well, it didn’t happen, and it still hasn’t.

When the KTM 950 came out, we thought “well, there you go, they built what we built, and it’s a 950 to boot”. Of course I bought one. And I found out immediately that the KTM is still not in the same league as the Rally Twin. It’s 100lbs heavier. The Rally Twin feels light and agile compared to the 950, like a 250 MX’er in comparison. And although the 950 is obviously more powerful, it’s only faster on very open sections. The Rally Twin is faster, and much more tractable, on any 4wd road. It’s also more stable than the 950, with a full degree of extra rake, and the same wheelbase. And the Rally Twin is infinitely tougher, more crashable, “chuckable” as described on a British site. The KTM isn’t really a bike you want to toss down on a rockpile, as those tanks that will touch the ground first cost $1100 each. The Rally Twin has been crash tested in every imaginable way, and the worst damage ever was a broken mirror, $33 for a Transalp mirror.

Is the Rally Twin supreme to the KTM950 in every way? No. It’s slower on the pavement, and the front brake isn’t as strong. But if I’m going on a long dualsport ride with unknown terrain, big rocks, sand, snow, or mud, I’m taking the Rally Twin.