2019 Factory Off-Road Bikes—Caleb Tate’s KTM 65 SX

KTM never envisioned that its 65 SX mini would be pressed into service as an off-road racer, but it's proven a viable option despite a dearth of aftermarket accessories targeted for that task.

So what Justin Tate came up with for 11-year-old son Caleb and teammate Brennen Watson to use in the 3 Bros. 10-hour Endurance Race at Glen Helen Raceway Park in San Bernardino, California, was not much different than what rolled off the dealer floor. And without a full machine shop, 3-D printers, and whatnot at his disposal, there was a limit to what he could do.

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Still, what Caleb and Brennen enjoyed racing for 10 challenging hours on a diverse course of just under 8 miles proved to be both quick and reliable as well as aesthetically pleasing.

“I didn’t really modify it much—just [tightened nuts and bolts], Loctite, go through it, and go through it again,” Justin admits. One of the items he added was a Nihilo Concepts polymer skid plate, since case-destroying rocks are a fact of life in the desert as well as many SoCal trails.

Factory Connection massaged the suspension, deeming a lighter-rate rear spring suitable for long races. Both fork and shock were also revalved to preference with some juggling of oil height in front and running 35 psi in the WP AER fork. Referring to his notebook, Tate reveals, “We run the sag between 85 and 90 millimeters.”

For controls, a Mika Metals handlebar (Mini Narrow bend) sits atop the stock triple clamp, and KTM hand guards ward off brush. While the seat foam is stock, the traction-ribbed cover is from Thrill Seekers.

Tate runs Dunlop Geomax MX52s front and rear, and though no commercially available foam inserts are available for the small stock wheels, he makes his own. He laughs, “There are mousses in that bike! We take the front [ones] from the big bikes and then we cut them down and we make them fit. Ty Davis from Zip-Ty Racing helped us with that.”

Stock 14/40 gearing suffices for their needs, though he adds a non-O-ring ProTaper chain.

The engine remains very stock with the exception of a Pro Circuit expansion chamber and silencer. Blud Lubricants provides all the lubrication needs including the engine oil, which is mixed 60:1 with premium pump gas; the cooling system holds Engine Ice coolant.

Small engines demand more frequent maintenance and Tate’s 65 SX is no exception: “Every couple rides we change [transmission oil]. Every time we ride, we change the air filter. [The] top end gets done at 15 about hours; we do a full top end [job] on it just to save on maintenance down the road. The sprockets and chain, we just keep an eye on it, and when we see the wear in them, we change it. I nut and bolt it all the time! We check jetting in the carburetor—just clean the jets out and stuff like that. Basic maintenance is keeping up on it and it keeps running!”

During the race, they simply tightened the chain once, replaced the air filter, and poured gas (a total of about 11 gallons over the 10 hours)—nothing else. Although a larger-capacity fuel tank would be nice, they’ve found nothing available, so they make do with the stock setup. Elusive Graphics provided the visually pleasing aesthetics for the 3 Bros. KTM/Kilmartin Racing machine.

The boys did well, starting off third and quickly working into second where they stayed the rest of the day. Ultimately, they finished second, about five minutes behind a team on a bike similar to theirs.