1970 Husqvarna 400 Cross

Few motocross bikes enjoy as colorful a history as Husqvarna’s 400 Cross.

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by Dain Gingerelli

Few motocross bikes enjoy as colorful a history as Husqvarna’s 400 Cross.

The production-based motocross racer, powered by its all-new 396cc 2-stroke single-cylinder engine, began life in 1969, winning the first of two consecutive 500cc World Championships in the capable hands of Swedish legend Bengt Aberg. Success also followed Malcolm Smith and Gunnar Nilsson who shared riding duties aboard a specially prepped 400 Cross to win the 1971 Baja 1000, and that same year a 400 Cross propelled Mark Blackwell to become America’s first official motocross Open-class national champion when he edged Brad Lackey by one point as top American in the Trans-AMA Series. The 400 Cross legend expanded that same year when two 400s were among the marquee stars of a full-length feature film that summer; most recently one of those two Husky Hollywood starlets sold at auction for nearly a quarter of a million dollars. More about that later, but for now let’s see exactly why this particular motocross race bike deserves its place in moto lore.

The late Tom White, whose private and very exclusive motocross museum included a 400 Cross, once said about the bike: “The combination of Husqvarna’s precise handling and incredible horsepower made this machine a powerful motocross weapon.” White added, “The 400 Cross was equally successful in the California desert and Baja under riders like Gunnar Nilsson, J.N. Roberts, Malcolm Smith and Whitey Martino.”

Yet even as Husqvarna’s 400 Cross began its steamrolling path across America, Cycle magazine espoused the bike’s brilliance in its September 1970 issue, citing that “Everything about the big Husky’s appearance denotes its intent. Race and Win.”

Additional praise appears elsewhere in that Cycle test. “All structural members and parts are just the right size,” wrote the editors. “The forks interact with the rear suspension. The front wheel is easy to keep up. Power is seemingly endless. Just dial on as much as you have guts for. It’s not bolt-of-lightning power, it’s the water main type: the more you open it, the more comes out.”

Similar accolades about the 400 Cross are found in Cycle World’s May 1969 test when the editors wrote that “the solid, low-rpm torque and smooth power band running all the way to 9,000-9,500rpm offer convincing proof of the benefits of increased displacement.”

No replacement for displacement

By now you begin to understand the bike’s brilliance, but it didn’t happen overnight. According to Gunnar Lindstrom, author of the book Husqvarna Success and who was a development rider for Husqvarna during the years leading to the 400 Cross, the big 400 actually was based on a development of Husky’s first “big-bore” model, the 360, itself a derivative of Husqvarna’s world-dominating 250-class racer.

The 360 suffered some minor transmission problems, which led to a redesign that spawned a new engine for 1967. The new 360 proved to be an improvement, but during that same time other European Open-class 2-stroke motocross racers had also upped their performance, effectively assuring the 360’s runner-up status in Grand Prix competition. Husqvarna’s solution, according to Lindstrom, was to increase the new engine’s displacement, initially trying 420cc. But, as Cycle World’s Joe Parkhurst pointed out in the magazine’s 1969 test of the 400 Cross, “boring the barrel to yield 420cc gave less than desirable results, because there wasn’t enough metal left to allow intake and transfer ports of proper shape and size.” As any 2-stroke aficionado will attest, intake and exhaust ports’ size, shape and configuration are where much of the oil-burning engine’s potential is found.

And so the Swedish engineers throttled down to a 396cc design that had a new bore and stroke, which necessitated relocating the case bolts to accommodate the larger cylinder bore dimensions. Husqvarna now had a new Open-class production racer. As pointed out, Aberg proved Husqvarna’s engineering posse had the right formula when he won those back-to-back world titles. Lindstrom himself is especially proud of the 1970 world championship season when the 400 dominated the 10-race Grand Prix series with teammates Aberg and Arne Kring winning 18 of the 20 motos (each GP followed the FIM’s traditional two-moto format).

“That (race success) led to a lot of demand (for the 400 Cross) here in America,” stated Lindstrom, his voice tinged with pride. Husqvarna dealers quickly sold out their allotment of 400 Cross bikes, “so Americans,” reflects Lindstrom today, “sought Swedish dealers willing to ship bikes directly to America where American racers paid premium shipping fees for their transport.”

Dyed in the wool MX fans

Students of American motocross history are familiar with Edison Dye, the man who set up Husqvarna’s U.S. distributorship. Dye realized right away the built-in advantages Husqvarna offroad bikes enjoyed over their competition, due primarily to the combination of powerful engines set in lightweight chassis. Mix those ingredients with precise steering and handling, not to forget ergonomics that lock the rider into full-on attack mode, and you have the makings of a championship motorcycle. Dye relied on that formula as he planned his next move of crowding American motocross tracks and enduro courses with gas tanks sporting the familiar red with white-and-chrome trim.

One of the first Americans to appreciate Dye’s philosophy was motorcycle dealer and competitor Malcolm Smith whose K&N dealership in Riverside, California, was geographically positioned to become a major beachhead for Dye’s assault on America. However, at the time Smith still favored the tried and tested Greeves that he’d raced for years. The British-built brand had an established record for scrambles and motocross racing in Europe and America, so Smith remained loyal, even though he realized Greeves were not only stout in stature, but heavy in weight. Consequently, Smith initially deemed the Husqvarna to be “spindly framed.” But after a few outings with the Scandinavian-built interloper, he figured that the Swedes might be on to something. In no time the Husky became the weapon of choice for Smith, and the rest of their story is legend.

The Husqvarna/Smith combination certainly cemented itself in American lore July of 1971 when the pair appeared in the movie On Any Sunday, also starring a fellow named Harvey Mushman, better known to Hollywood fans as Steve McQueen. And like Smith, Mushman/McQueen rode a Husqvarna, and both men, along with their bikes, commanded the silver screen during various OAS scenes that included a visit to the 1970 Elsinore Grand Prix, won by Smith; Mushman (McQueen’s racing pseudonym that concealed his racing endeavors from the film studio’s suits) finished in the top 10. In the process those exploits forever changed motorcycling in America. (See the On Any Sunday story.) And, recall that quarter-million dollar 400 Cross? That was the 400 Cross with frame number MH1341, the same bike that McQueen rode in the On Any Sunday’s closing sequence showing Smith, McQueen and the film’s third powerhouse personality, Mert Lawwill, playfully riding their dirt bikes on a broad sun-soaked beach that stretched right into the vast Pacific Ocean.

It turns out the beach was part of the U.S. Marine complex of Camp Pendleton in Southern California where the riders had to follow military security protocol by checking in their equipment before riding. Documentation confirms that frame number MH1341 was McQueen’s bike, and for the record, Smith’s 400 Cross was bike MH1221 (now displayed in the AMA Hall of Fame) while Lawwill’s Greeves, painted to look like a Harley-Davidson, was number 36MX4C139 (Lawwill was a factory-sponsored Harley-Davidson racer, so a Greeves affiliation was a no-no in his contract). Recently bike MH1341 sold at a Barber Museum auction for $230,500.

Less is more

McQueen’s Husqvarna certainly carried with it a unique provenance, but otherwise his bike, like all other Husky 400s sold in America, didn’t boast much cutting edge technology, especially by 1970 motocross standards. In truth, the 400’s advantage was found in the sum total of its parts. Like other Husqvarna models of the era, the 400 Cross leaned on contemporary technology to win; a single-loop frame suspended by a telescopic fork and twin Girling rear shock absorbers carried a rather conventional 2-stroke engine. Rather, it was the manner in how the Swedes executed the package that made the difference, resulting in a bike that represented, as Cycle stated, “the latest in current motorcycle specialization — the ultimate in weapons to wage the motocross war.”

Clearly, though, the 396cc engine was the 400’s nerve center. Its standard port layout included Siamesed intake ports, two transfer ports and one exhaust port. Its large-finned alloy cylinder used a pressed in, centrifugally cast, cast iron liner. The cooling fins’ configuration was unique but subtle in design, too; the cylinder head used large fins on top, and short fins pointed down towards the top of the air-cooled cylinder barrel, creating a visual gap that allowed for more cooling air to flow between the head and cylinder. The gap formed what amounted to a credible heat barrier to insulate the cylinder from the radiant heat created by the head’s combustion chamber. The engine’s flat-black finish, rather unique for 1970, further helped dissipate heat.

Perhaps the 400’s most cutting-edge technology is found on the flat-dome piston where a single ring was used. After testing, the engineers determined that a single chrome-steel ring (rather than the customary two rings) was sufficient for sealing compression, which was set at a beefy 10.5:1. Husqvarna claimed that the ring could be twisted into an “S” shape without kinking or breaking, so it was plenty reliable. Although many people feel that using a single ring helped minimize frictional drag on the cylinder walls, truth was there was no mechanical advantage to it; simply, the single ring was more economical, so this round belongs to Husqvarna’s bean counters!

The crankshaft assembly had small diameter flywheels joined by the chrome-nickel crankpin, which was tight-press fit, and rode on double-row ball bearings. The connecting rod had caged needle bearings at both ends. Toss in a reconfigured expansion chamber exhaust pipe and a refined Bing carburetor, and the net result was, in Cycle’s words, “tremendous torque [that] pulls it [the bike] with ease.”

The transmission shared similar heavy-duty design treatment. For instance both transmission shafts rode on ball or needle bearings, and the nickel-chromed gears and shafts, although small by contemporary standards, were deemed extremely rugged by Cycle magazine’s staff. They also cited an update by Husqvarna that cured a problem with the transmission’s original engaging dogs.

Spindley framed? Ha!

That cool-looking red-withchrome- inserts gas tank aside, perhaps the most compelling feature about Husqvarna racers of the era were their frames. Even though there was nothing groundbreaking about the 400’s frame, the manner in which it was pieced together made it a thing of beauty. No doubt, part of the reason for its “spindly” appearance was that Swedish steel was among the world’s best, allowing Husqvarna engineers to use comparatively strong, yet smaller diameter tubing, in critical sections of the frame’s layout. Plus Husqvarna chose chrome-moly, a lightweight metal, for the 400’s frame structure. And by eliminating any bolt-on subframe as found on the earlier 360, the 400’s single-piece frame was among the strongest and most rigid of its time.

Trelleborg tires were standard equipment that wrapped around lightweight Akront rims laced to new and bigger hubs containing large drum brakes (6.25-inches at the front, considered huge for the time). Again, pulling from Cycle’s test, “The indecently fast 400 needs this much more brake to slow it down.”

Come to Papa

As you might expect, a 400 Cross today commands a rather hefty price tag on today’s collector-bike market. A few years ago motorcycle collector and restorer Kenny Easton of Fullerton, California, came upon this 1970 edition that was in need of some TLC, paying what he considered “a fair price.” “I bought it from the original owner who lived in Salinas, California,” Kenny says. “He raced it in the desert for years. He told me that one day while on the starting line he looked across and noticed a sea of red [referring to the swarm of redtank Husqvarnas]. That’s when he decided to paint the tank blue.” Ouch!

After stripping the tired blue paint, Kenny found the tank to be in excellent condition, allowing him to keep the original chrome. As a former body and paint man, he does all his own painting, plus he reupholstered the seat and polished the bare metal components.

“I do my own metal polishing, welding, wheel lacing and truing, plus general mechanical upgrades,” Kenny says, leaving serious engine work to experts like John LeFevre at Vintage Husky. Overall, Kenny says his project bike was in rather good condition. “I only had to replace or freshen it up cosmetically,” That included replacing the Preston Petty plastic fenders — standard ware on bikes from that era — with original-style alloy units, and back-dating a desert-racing handlebar with a more original Husky bend. Most of the replacement parts were acquired from Kenny’s primary source, Vintage Husky in nearby San Marcos, California.

In truth, this was Kenny’s fourth restoration. He now has about a dozen bikes in his collection, most of them restored after retiring from his job as an insurance adjuster. His Husky journey actually began years ago as a lad when he bought a 1969 250 that allowed him to join his friends on trail rides in the desert.

“That little Husky was so nimble, so fast, that I fell in love with them [Husqvarnas],” Kenny says. During one ride he swapped bikes with one of his buddies who owned a Japanese offroader, and “it felt like a truck compared to my 250.” That forever cemented his affection for Huskies.

As for restoring old bikes, it was only a few years ago that he spotted a vintage bike calendar featuring restorations by an old friend of his that sparked Kenny’s interest into having his own classic bike. After that first restoration he located another project bike, and eventually the collection brought in the 400 Cross, which later was joined by a 1971 model, and, well, his garage is now getting rather full, including several Bultacos, plus a lone Rokon two-wheel-drive bike. All his bikes are restored to the level of the 400 Cross featured here. “This bike is rather special, too,” cited Kenny. “I displayed it at the annual Steve McQueen Car and Bike Show one year. That was a very special outing for it.”

You can bet, too, that Harvey Mushman himself would have given that performance a two thumbs up. MC

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