Up until 2013 the MXA wrecking crew included KTM’s 350cc four-stroke in our yearly 450cc four-stroke shootouts. But, starting in 2014, we excluded the 350 from the 450 shootout for the simple reason that it wasn’t a 450. Because of that simple mathematical reality, it couldn’t win. Why not? It was lacking the one thing that makes a 450 a 450—10 more horsepower at 8000 rpm. Our decision to drop the 350 from the 450 shootout earned us some grief, but we stuck to our guns. We offered solace by promising KTM 350SXF owners that “it would win MXA’s 350 shootout.”
RACING A 350 HAS ALMOST NOTHING IN COMMON WITH RACING A 450—THE 350’S CLOSEST SIBLING WOULD BE A 250 TWO-STROKE (OR EVEN A 125 TWO-STROKE).
Roger DeCoster knows exactly what we were thinking. When he came to KTM in 2011, the Austrian conglomerate was planning to drop the KTM 450SXF from its lineup and replace it with the 350—all 350s, all the time. Roger was appalled. He knew that the brute power, massive torque and instant hookup of a 450cc engine could not be duplicated by a 350, and he told KTM’s management so. Roger didn’t want to have his team racing on 350s against the works 450s of Honda, Yamaha, Suzuki and Kawasaki. Not because the 350 was a bad bike, as it makes more peak horsepower than the CRF450 and has close to the same output as the RM-Z450, but because the inherent problem was in reaching the 350’s peak power. A 350 rider has to rev the engine almost 4000 rpm more than a 450 rider to get to peak horsepower. With peak at 13,400 rpm, the 350SXF screams bloody murder on its way to its impressive numbers. For Roger’s needs and MXA’s 450 shootout, by the time the 350 reaches the sweet spot, the grunty 450s are long gone.
It doesn’t take a genius to realize that 350s can and have beat 450s many times. And you could easily argue that Antonio Cairoli is proof positive that the 350 is a competitive machine. Without a doubt, a rider can win on a 350, but that doesn’t make it into a 450. Racing a 350 has almost nothing in common with racing a 450—the 350’s closest sibling would be a 250 two-stroke (or even a 125 two-stroke). Success on these three machines comes from hitting it hard, leaving it on long and never shutting it off. If you did that on a 450, you’d end up in the trunk of a car parked in the pits.
In all honesty, MXA has lobbied the powers that be at KTM (and now Husqvarna) for years to reconfigure their 350 formula—after all, they built the original 350cc engine to meet a threat by Giuseppe Luongo to ban 450 four-strokes from Grand Prix racing. That never happened, and, as a result, KTM built a bike without a class to race in. Most MXA test riders think that a mid-sized Open bike, say 380cc to 400cc, would suit a wider range of riders than a hopped-up-on-Adderall oversized 250. A mid-size 400 would produce more power in the midrange, have a torquier feel down low and allow the current 350cc riders the opportunity to ride harder in the meat of the powerband (instead of waiting for the powerband to come around at 13,400 rpm).
But, KTM and Husky have turned a blind ear, if there is such a thing, to MXA’s mid-size dream machine. So, we decided to do something about it. No, we didn’t melt down aluminum ingots and cast our own engines. No, we didn’t build a big-bore 370cc cylinder on a CNC-machine. No, we didn’t stuff an old-school KTM 400XC engine into the current chassis. No, no, no. Instead, we had Husqvarna build us a complete Factory Services FC350 engine that we believed could compete head-to-head against a 450. Our real goal was to enhance the bottom and midrange power without changing the displacement. We wanted to find out if it was physically possible to squeeze 450-style power out of an engine that is 100cc smaller.
We already knew how the FC350 ranked against the FC450, but decided to double-down on the 350 engine.
TRUE, IT WOULDN’T BE A PURE 350 VERSUS 450 SHOOTOUT BECAUSE THE FACTORY SERVICES’ FC350 ENGINE WOULD BE HOPPED-UP TO THE HILT, BUT IT WOULD BE A FAIRER SHOOTOUT THAN COMPARING STOCKER TO STOCKER.
If you have never heard of Factory Services, it is responsible for building the entire fleet of Factory KTM and Husqvarna race engines—including Ryan Dungey’s KTM 450SXF and Jason Anderson’s Husqvarna FC450. Sadly, if you want the same engine as Ryan Dungey, you can’t have it. There was once a small window of time when anyone could buy a Factory Services engine package. They were high priced (because they were full-fledged factory engines) and there were strict rules for anyone who bought one. But, that window snapped shut when Factory Services decided that it was too busy building engines for the Red Bull, BTO and Troy Lee Designs teams (and by happenstance, the MXA wrecking crew). Thus, you can’t get the engine we tested, but don’t sweat it. We have raced Pro Circuit-tuned KTM 350SXF engines that run almost as well as the works engines for a lot less money.
Back in 2013, Factory Services built MXA a copy of the engine that Ken Roczen raced at the Daytona Supercross. The engine screamed to 15,000 rpm and produced an incredible 57.90 horsepower. That is only a smidgen below what the 2016 KTM 450SXF produces (57.98 horsepower). Roczen’s engine, which he only raced one time, gained 2 to 3 horses from 8000 to 11,000 rpm, but at 12,000 rpm it hit the afterburners and made 7 more horses than stock and even more at 13,000 rpm. Needless to say, we were impressed. Not surprisingly, we treasured our Roczen 350 engine and used it every year—until, in 2016, it wouldn’t fit in the all-new frame. We gave it back to KTM grudgingly.
Then, a lightbulb went off in our heads. What if we had Husqvarna build us a Factory Services-powered 2016 Husqvarna FC350? We could then take that engine and compare it against a stock 2016 Husqvarna FC450. True, it wouldn’t be a pure 350 versus 450 shootout because the Factory Services’ FC350 engine would be hopped-up to the hilt, but it would be a fairer shootout than comparing stocker to stocker.
YOU COULD TELL BY THE LOOKS ON THE FACES OF THE MXA WRECKING CREW THAT THEY DIDN’T UNDERSTAND WHAT WE WERE DOING. THEY KEPT ASKING QUESTIONS SUCH AS, “WHAT ARE WE TESTING?” AND “ISN’T THIS LIKE TESTING APPLES AND ORANGES?”
You could tell by the looks on the faces of the MXA wrecking crew that they didn’t understand what we were doing. They kept asking questions such as, “What are we testing?” and “Isn’t this like testing apples and oranges?” We explained it to them several times, but finally we told them to shut up and ride. Every time they made the switch back and forth from the stock FC450 to the Factory Services FC350, you could tell by the looks on their faces that they were in deep thought. Their first assessment was that the FC350 felt lighter and more nimble than the FC450 (even though there is only a 2-pound difference between the two). They also said that the 350’s powerband required them to rev the engine to the moon—and that on many parts of the track the moon was hard to reach (this was especially true for our Vet test riders). We constantly reminded our test riders that this was strictly an “engine comparison” and to ignore the handling differences except for where they applied to power delivery. After our first round of testing, engine to engine, it was the unanimous decision that the FC450 had a better all-around engine package.
But, this wasn’t the end of the road. We had one more trick up our sleeves. It’s no secret that underneath Husqvarna’s “Ode to Sweden” color scheme lies a KTM engine and chassis. But, from the day we tested our first Austrian-built Husqvarna, we noted that the Husky’s powerband felt vastly different from the identical engine in a KTM. Since the engines are spitting images of each other and the only major difference is the Husqvarna’s plastic subframe, we surmised that the culprit was the Husky’s airbox. We quickly learned that all of the Husky airboxes are sealed up tighter than King Tut’s tomb. The restricted airflow dulls the powerband into a slower revving, more linear curve that in some situations is a plus and in others a minus.
If Ryan Dungey, Jason Anderson or Christophe Pourcel decided they wanted to race a 350 instead of a 450, this is the engine that Factory Services would give them.
As a final test, we pulled the left side panel off the Factory Services FC350 and sent the test riders back out on the track. Each and every MXA test rider came back wide-eyed and enthusiastic. Obviously, we couldn’t keep testing the FC350 without any plastic on the left side (largely because the radiator was exposed and our boots kept unhooking the air filter strap), so the solution was to drill holes in the airbox (and cut a large chunk out of the right side of the airbox). We can’t over-state how much difference this small change made to the FC350. It turned it into an entirely different animal. The brunt of the power was now from bottom to mid instead of way up top where only non-shifters and the chronically fast could reach it. The revived powerband catapulted our test riders out of corners with no need for the clutch. Make no mistake about it, the Husqvarna FC350 runs better with more air. The same holds true for the FC250 and FC450. Of course, our fully breathed-on Factory Services engine placed greater demands on the Husky’s air flow system than a stock engine—which accounts for our greater reward. Now, the power was where we needed it and when we needed it, but was it enough to beat the FC450?
At this point, the MXA test riders weren’t puzzled anymore. With just the airbox change we sent them back out to start all over again. During this final round of testing, many of our test riders couldn’t make up their minds between the two—which was a complete reversal from earlier in the day when they were all Team FC450. As a group, they felt the FC450 had better traction on hard-packed terrain, while the Factory Services FC350 excelled on loamy and fast tracks. At the end of the day, we had a split decision. Although the FC450 and the Factory Services FC350 engines are vastly different, we learned that a 350cc engine with a 100cc disadvantage can run with the best of the 450cc class—although it takes some hard-earned cash and a very sharp drill bit.