KTM 350 SX-F | Doin' Time

Staffers' Rides

Ringleader: Brian Catterson
MSRP (2011): $8499
Hours: 34
Mods: Rebuilt engine

The 800-lb. gorilla in the photo is my long-term KTM 350 SX-F’s left-side exhaust cam. Even untrained eyes will detect there’s something wrong with this picture: some discoloration, galling and, oh yeah, shouldn’t there be an actual lobe on that cam? Indeed there should.

In my last update, I’d just worn the “new” off my shiny orange Katoom by competing in the resurrected Catalina Grand Prix. That was a pretty highfalutin race debut, but following that it was back to the gritty reality of the weekly REM Saturday-morning motocross races at Glen Helen.

Early outings boded well: After learning that I could still nail holeshots on the “little” 350 and posting a couple of top-five finishes in the hotly contested 40-plus Intermediate class, the KTM and I were looking pretty good. Then, it happened.

One Thursday, while practicing on Glen Helen’s USGP track, the bike started to stall with increasing frequency. Then the top end started to clatter at high rpm, similar to what you’d hear when the valves need adjusting. And then it made a really bad noise. Worried what that might be, I parked it. A subsequent autopsy revealed that the left-side exhaust cam was badly galled, legacy of a clogged oil jet—this despite routine oil-and-filter changes. Even worse, it had spit a shim, which worked its way down to the bottom end, requiring the cases to be split.

This is where being a “magazine guy” has its privileges, because I was able to return the bike to the importer for repairs, free of charge. What would have happened to a regular customer? According to KTM USA, if the bike was past its 30-day “competition warranty” period and the dealer thought it was a warranted problem, it would be dealt with on a one-by-one basis. Thus there’s a strong chance the engine would be repaired as an act of goodwill. But if the bike showed signs of abuse or neglect, it could be denied, and the owner would be looking at a four-digit repair bill.

I’ve got the 350 back now and it’s again running great. Hopefully, this won’t be a recurring problem…

An oiling issue led to failure of one of the 350’s exhaust cams. This has been a problem on some early examples, though most just wore the hard facing on the cam follower.