MXA RETRO TEST: THE BROCK SELLARDS KTM 200SX EXPERIMENT

On Jul 21, 2023 Last updated Jul 21, 2023

We get misty-eyed sometimes thinking about past bikes we loved, as well as ones that should remain forgotten. We take you on a trip down memory lane with bike tests that got filed away and disregarded in the MXA archives. We reminisce on a piece of moto history that has been resurrected. Here is our test of Brock Sellards’ very unusual 2001 KTM 200SX two-stroke.

We know what you’re thinking—what is Brock Sellards doing riding a 200cc two-stroke in the 125 class? Is this KTM’s way of protesting the 125cc advantage that 250cc four-strokes get? No wonder Brock finished fifth in this year’s AMA 125 Nationals. But, it’s not what you think.

**The engine for Sellards’ one-off KTM 200SX came out of the off-road model. It didn’t make a lot more peak power, but had plenty of low-end power.**

KTM been not been cheating in the 125 cheating with a 200? The answer is less sinister. At the 2001 U.S. Open in Las Vegas, KTM wanted to race a 200cc two-stroke engine in the 250cc class. Why would any factory want to put its rider at a serious horsepower disadvantage right from the git-go? We wish we had a plain and simple answer, but it’s more complicated than that, and that’s why we went out of our way to get our hands on Brock’s special KTM 200SX. The cast titanium footpegs rival anything around 20 years later.

WHY DID KTM DO IT?

The triple clamps were machined out of magnesium to save weight.Why did KTM put Brock on a 200? There are three reasons:

(1) Brock has spent more saddle time aboard a 125 than a 250 — and the KTM 200SX is more akin to the 125SX than the 250SX. The KTM 125SX and enduro-based 200EXC use the same frame and engine cases. The only differences are bore-and-stroke and suspension settings. Since Brock was comfortable with his KTM 125SX, the team felt that he might adapt to the 200 better than the 250.

**Brock’s works WP forks featured tighter tolerances, special coatings and a jumbo-sized 30mm front axle.**

(2) KTM calculated that the power-to-weight ratio could work out to be equal to that of a heavier 250. Although Brock would give up 50cc to real 250s, he would also have a bike that weighed as much as 25 pounds less than the competition. Plus, the tight confines of the MGM Grand would favor 125 handling. It was a gamble based on hopeful mathematics. Additionally, in all fairness, Brock probably didn’t have the speed to hang with Carmichael, McGrath, Ferry or Windham no matter what he rode. The 200SX would give Brock incentive to ride harder and KTM an added dose of publicity.

**Works hubs, stronger spokes, Brembo brakes and gold Excel rims highlighted Sellards’ one-and-done machine.**

(3) KTM is testing the waters for the possibility of a production version of a 200SX motocross bike in the future. You’re probably confused. Currently, KTM only sells the 200 in an EXC enduro version. However, they are thinking of stripping the lights and making a full motocross version of it to cater to Over-25 and Vet racers who like the feel of a 125 but need more horsepower.Built for the 2001 Las Vegas U.S. Open, KTM thought that Brock Sellards’ 125 Supercross experience would be better used by building him a special 200cc two-stroke for the 250 class.

MORE IS MORE FUN

What’s it like to ride Brock’s KTM 200SX? Lots of fun. It’s amazing how much bottom an extra 50cc adds to a tiddler. Brock’s 200SX had the strong midrange and unlimited rev of the 125SX, but was enhanced by stronger low-end. You might be surprised to learn that on the dyno, the 200SX is only marginally stronger than a standard 125SX. But what it lacks in numbers, it makes up for in hit. It’s quick, hard-hitting, light and agile.