MOTOCROSS ACTION MID-WEEK REPORT

#WHIPITWEDNESDAY

Rider: Ken Roczen
Race: 2021 Indy SX 2
Bike: Factory HRC CRF450
Photographer: Trevor Nelson

WE WILL NEVER FORGOT THE 70-HORSEPOWER KTM TWO-STROKE WE TESTED

_1040131_LRIt’s apparent that people’s love for two-strokes is only exceeded by their fascination for exotic two-strokes. Thank Jeff Moffet for fulfilling a dream and sharing it with the world. The Oregon Motorcycle Adventures KTM co-owner envisioned a motocross bike where he would meld modern-day technology with unbridled power. Moffet succeeded, evidenced by the attention the bike received in the Glen Helen pits back in 2015 when we were riding it. Little did we know that shoving a 550cc two-stroke engine inside a 250SXF Factory Edition chassis would be such a hit. In fact, MXA received multiple calls from interested readers who inquired about purchasing the bike after the story graced the pages of MXA. It wasn’t for sale.

_1040159_LRHow did Jeff Moffet produce the insanely cool KTM? Here’s the short story. Moffet sold the 2015-1/2 KTM 250SXF Factory Edition engine to a guy who wanted it for a dirt race shifter Kart. Jeff had a rolling chassis, only without an engine to make it go. That’s when he found a 1994 550MXC engine—a displacement KTM made for several years to target sidecar and offroad racers. With the pieces in place, Moffet enlisted the services of Tiginet Fabrication to shoehorn the massive engine into the frame. Tiginet fabricated the new frame down tubes. From there Moffet and crew reversed the rear wheel, as the drive train is on the right side of the KTM 550MXC engine. They machined the swingarm for the left-side caliper and used the stock caliper off the 1994 KTM 550MXC. The rear brake was moved to the outside of the frame and comes off a KTM LC4 640 supermoto bike. Moffet took the airbox and filter off the 550MXC and fit it on the 250SXF Factory Edition. That’s not all Jeff had to do. He machined a wedge off the intake flange to move the carburetor in order to clear the rear shock. The team cut the reservoir off the rear shock and mounted it under the seat. They drilled and tapped and installed a braided line. Pacific Pipe Repair cleaned and restored the stock 550MXC pipe, while Moffet relied on an FMF Shorty silencer that was fitted by JENFAB Fabrication. Finally, Moffet used a 2016 KTM 150SX gas tank.

_1040135_LRIf you haven’t been keeping track, Jeff Moffet’s amalgamation uses parts off four different bikes. Another key piece of noteworthy information is this–the 1994 KTM 550MXC engine produces around 66 horsepower in stock trim. Impressive enough, but Moffet couldn’t leave well enough alone. He had the engine modified for even more power. We’re guessing the bike produced 70 ponies. A useful tidbit is how the bike had a left-side kick starter. We stood on the left side of the KTM and kicked with our right legs. It reminded us of the old days when a variety of motorcycle brands used left-side kick-starters.

How did the bike run? Was it the coolest thing since sliced bread? We only got three laps on it until it broke down. Although those three laps, we will remember forever.

RAW VIDEO OF ONE OF THE COOLEST LOOKING HUSKY TC250 TWO-STROKE

MXA | MOTO | TRIVIA

Who is this KTM SX rider and what year was it? Answer at the bottom of the page.

ADAM CIANCIARULO PUTS HIS TRUST IN POD KNEE BRACES

MXA FIRST RIDE | 2021 1/2 KTM 450SXF FACTORY EDITION WITH BLUETOOTH

TRAVIS FANT GETS SHOTS OF THE  STAR RACING 250 WEST COAST RIDERS AT THE YAMAHA TEST TRACK

JEREMY MARTIN StarRacingYamaha2021SupercrossTestTrack-4Jeremy Martin’s Star Racing mechanic, Derik Dwyer putting the finishing touches on his bike. 

This will be Nate Thrasher’s rookie Supercross season. 

The rookie Jarrett Frye. 

JEREMY MARTIN StarRacingYamaha2021SupercrossTestTrack-4Jeremy Martin should be a championship threat this season. 

The whoops look treacherous at the Yamaha test track. 

The West Coast Yamaha 250 team putting in the laps. 

HAVE YOU SEEN THE FEBRUARY 2021 ISSUE OF MXA YET? SPECIAL SUBSCRIPTION OFFER BELOW

What’s in the newest issue of MXA? How about Shootout between the 2021 Honda CRF450 and the 2021 Husqvarna FC450—go ahead and guess which one won, you have a 50/50 chance of being right. Or how about complete and thorough tests of the 2021 KTM 450SXF, 2021 Yamaha YZ250F, 2021 Kawasaki KX450F cross-country, 2021 KTM 250SXF and Carson Brown’s BBR Honda 190.

We wanted to take a little confusion out of what is the most confusing shootout season ever by doing shootouts against worthy contenders—this month it was the 2021 Honda CRF450 against the 2021 Husqvarna FC450.

Why is MXA testing the 2021 Kawasaki KX450X cross-country bike? That’s simple, we race cross-country races, SRA GPs, WORCS races and endurance races all the time. And since the KX450X is just a KX450 motocross model with a few off-road concession, we felt right at home on it.

The 2021 KTM 250SXF is a high-rpm rocket ship that just happens to be blessed with a strong midrange and usable low-end. This is the magic formula for success in the 250 class.

The 2021 Yamaha YZ250F has the perfect low-to-mid powerband for the average racer or play rider. It doesn’t have the high rpm power of the KTM, Husky, GasGas and Kawasaki, but it gets out of tight corners better.

In the hierarchy of Austrian motocross bikes the 2021 KTM, 2021 Husqvarna FC450 and 2021 GasGas MC450F managed to use the same shared package three different ways. If you asked KTM what the 450SXF was designed for, they would tell you that it was “Ready to Race.” We concur.

HOW TO SUBSCRIBE TO MXA SO THAT YOU NEVER MISS ANOTHER ISSUE, PLUS GET A $25 ROCKY MOUNTAIN GIFT CARD TO COVER YOUR COSTS

If you subscribe to MXA you can get the mag on your iPhone, iPad, Kindle or Android by going to the Apple Store, Amazon or Google Play or in a digital version. Even better you can subscribe to Motocross Action and get the awesome print edition delivered to your house by a uniformed employee of the U.S. Government. Did we mention the $25 gift card for any part you want from Rocky Mountain ATV/MX? You can call (800) 767-0345 or Click Here (or on the box at the bottom of this page) to subscribe.

LOST BUT NOT FORGOTTEN | BBR YZ80 CHASSIS WITH XR100 ENGINE

BBR YZ80 CHASSIS WITH XR100 ENGINE
BBR YZ80 with an XR100 engine. 

BBR YZ80 CHASSIS WITH XR100 ENGINE

This BBR Motosports build was built in 1994-/95. It is based on a YZ80. It used an XR100 engine. BBR custom built the frame, tank, air box, hubs, clamps, pegs, etc. And all on a manual mill and lathe. It was featured in the April 1996 Dirt Bike issue and the August 1996 issue of  MXA along with BBR’s 250 and 400. Still, 25 years later the OEMs can’t build a good play bike for the backyard as well as BBR. BBR is still building trick one-off bikes.

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CLASSIC PHOTO

Gaerne Boots 2000A set of Gaerne boots from 21 years ago.


Moto Trivia answer: The answer is Ryan Terlecki in the year 2000.

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