Swinging Singles: A Pair of Bultacos

Bultaco Metralla Mk2/Kit America

 Engine: 244cc air-cooled single, 72mm x 60mm bore and stroke, 38hp @ 9,500rpm

Top speed: 105mph plus

Carburetion: Single Mikuni (original 30mm Amal 389 GP)

Transmission: 5-speed, GP clutch

Electrics: Femsa electronic ignition

Wheelbase: 51in (1,275mm)

Suspension: Ceriani 35mm telescopic fork; Betor 11.5in shocks

Brakes: Recycled Japanese drum (front and rear)

Tires: Dunlop 2.75/3.75 x 18in KR823 front, Avon 110/80-VB18in rear

Weight: 241lb (110kg), period test of stock Mark II

Price then: $699 (stock Metralla)

There was something special, even magical, about Grand Prix motorcycle road racing in the 1960s that makes it so unforgettable to this day. Engines of that era led to cutting-edge technology, creating some of the most incredible race bikes ever.

While British warhorses from the 1950s, powered by archaic single-cylinder 4-stroke engines flinging massive pistons the size of coffee cans, continued populating the grids in the 350cc and 500cc classes, change was nevertheless in the wind. And the wind blew both from the West and from the East as engineers, especially in Italy and later Japan, perfected the art of increasing engine performance by upping the number of cylinders found on those race engines. The Italians fired the first volleys in the 1950s when Gilera and Moto-Guzzi determined that more cylinders generally equated to more power … and speed. Moto-Guzzi even built a V8!

By the 1960s, MV Augusta had inline triples and fours, and shortly thereafter from the East came Honda, closely followed by Yamaha, Suzuki, and later, Kawasaki (the latter three marques using 2-stroke technology that helped usher in the rotary disc-valve intake concept). The multi-cylinder rockets from the Orient ceremoniously sprouted cylinders in every which way; Yamaha favored V4 layouts while Suzuki seemed more comfortable with square fours; Honda spread its 4-stroker pistons and cylinders all in a row, first with the 125cc, 250cc, 350cc and 500cc fours, and finally with the inline 5-cylinder 125cc and 6-cylinder 250- and 350-class racers. By 1968 Suzuki was even developing a 3-cylinder 50cc engine, although FIM rules for 1969 finally put a cap on the number of cylinders per class (the 50cc class in particular was limited to single-cylinder engines), ultimately squelching that project.

But as the undeclared Cylinder War intensified into the 1960s, a new and rather small motorcycle company discreetly popped up in the corner of Europe otherwise known as the Iberian Peninsula. Bultaco, with its 125cc single-cylinder 2-stroke using the time-honored piston-port induction, was gearing up to market its first-ever model, the Tralla 101. Few members of motorcycle racing’s elite took notice when, only a few months after Bultaco’s official launch in February 1959, the company’s fledging racing department showed up at the Spanish Grand Prix with a small squadron of production-based Tralla 101s entered in the roadster-class support race. The untested Bultaco racers finished 2nd-5th and 7th-9th in front of the home crowd, proving that sometimes less can be more. That was only the beginning. There was much more, in terms of road racing, to come, and all the notable Bultaco competition bikes that followed relied on the same basic single-cylinder, piston-port design as that first little 125. Bultaco road racers, ranging in displacements from the first 125cc single up to a 360cc derivative, made their mark in road racing history, and the tradition continued into the 1970s and 1980s when Bultaco-mounted riders won four 50cc World Championships (1976-1978 and 1981).

Enter the TSS

Perhaps the most notable Bultaco road racers, though, were the TSS-based 125-class and 250-class models that also were offered as production racers to privateers, a concept also shared by Yamaha with its early TD- and TA-based 250s. Bultaco’s TSS marketing propaganda from the time summed it up best, stating, “The probabilities of winning any of the classic races counting for the World Championships are remote. However, it [TSS racer] should provide you with enjoyment and stand a reasonable chance of success in any other event in which official representative teams [read: factory-backed teams] are not participating.”

In addition, Bultaco offered a conversion kit in 1967, marketed as the Kit America, which transformed the spunky Metralla Mk II 250 street bike into a viable club racer. A small investment by any Metralla Mk II owner resulted in a worthy road racer using Kit America’s engine and race-body components.

But the TSS models were purpose-built racers, the first to appear being the 125 in 1961. The spunky TSS eighth-liter engine corralled its 20 horsepower into a 4-speed transmission. Most Bultaco enthusiasts feel the letters TSS stand for Tralla Super Sport, although people closer to don Francisco Xavier Bulto, the man who formed Bultaco in 1958, feel that the company’s figurehead was so enamored with Velocette’s successful KSS sports roadster and KTT racers that he named his racers with similar nomenclature, using the initials TSS. Regardless, the package was enough to help R.B. Rensen place 6th in the 1961 Isle of Man’s Ultra-Lightweight TT; he also was the highest-placing privateer rider in that race, averaging a respectable 83.26mph. Later that year Bultaco factory test rider John Grace placed 5th at the Spanish GP, followed closely by teammate Ricardo Quintanilla in 6th. The TSS legend was born, and it grew with a 196cc engine to contest the 250cc class in 1963. That little engine gained liquid cooling and displacement was upped to 244cc for 1965. A 6-speed transmission also joined the mix, and the payoff was higher finishes in World Championship competition.

By 1966 Bultaco hit the jackpot when privateer Ginger Malloy led a Bultaco 1-2-3 sweep at the rain-soaked Ulster GP, marking Bultaco’s first-ever win in Grand Prix competition. And in the 350 race a specially prepped Bultaco, its single cylinder displacing a class-legal 252cc, finished third with veteran racer Tommy Robb twisting the throttle. No doubt, the little engine that could, finally did.

On the road

Señor Bulto and his staff didn’t restrict their speed secrets to the racetrack though. Nope, and as author Geoffrey Wood pointed out in the January 1970 issue of Cycle World magazine, “Probably the most popular [Bultaco] model with the European crowd is the Metralla Mk II — a fast 250cc roadster with a strong pseudo-racer accent. The Metralla mill shoves out a healthy 27.6hp at 8,700rpm, which provided a maximum speed close to the 100mph mark. The sleek Single has a 5-speed gearbox.”

Interestingly, the Mk II, introduced in 1967, replaced the original Metralla 62, which had a 196cc engine with bore and stroke of 64.5mm x 60mm, and 10:1 compression ratio. The subsequent Mk II’s larger 244cc engine boasted bore and stroke of 72mm x 60mm, with 8.5:1 compression ratio.

Wood further pointed out how successful race-kitted Metrallas were doing on the European and American racing scenes. Wrote Wood: “Another bonus with the Metralla is the ‘bolt-on’ racing kit, which can be used to convert the roadster into a competitive racing bike. The kit includes a small head fairing, larger fuel tank, clip-on bars, seat, a rearset brake-gearshift-footpeg setup, a special cylinder with wilder porting, a special squish head, larger carburetor, a piston, and an expansion box exhaust system. By fitting these parts, plus a set of road racing tires, an owner can go road racing in respectable manner — especially in ‘production’ model races.” Grouped and sold together, those components were known as Kit America.

The Metralla now wears a Mikuni carb (top) instead of the original Amal. Owner Roland Ortiz aboard the Metralla.

Indeed, Metralla Mk IIs equipped with Kit America engine goodies were the scourge of the 250cc production-class race at the 1967 Isle of Man TT, which also happened to be the Diamond Jubilee celebrating the classic event’s 50th year. Metralla-mounted Bill Smith and Tommy Robb certainly celebrated the occasion, finishing first and second, averaging 88.63 and 88.62mph respectively; their overall finishing times would have netted sixth and seventh in the 750cc production-class race!

By then more than eight years had passed since Bultaco the company had been formed, yet its engineers insisted on retaining the tried-and-true piston-port, single-cylinder concept. Again, lifting narrative from Cycle World, this time from the November 1967 issue featuring a test of the Metralla Mk II — the words more than likely written or heavily edited by editor Ivan Wager who appreciated simple, yet fast, machines — stated: “The engine is … as exciting as a stone axe. It employs a Dykes-pattern piston ring, deep barrel spigoting, needle, ball and roller bearings throughout and a faultless drum-shifter 5-speed transmission, and the motorcycle doesn’t weigh very much. Fact of the matter is, the Metralla engine is a pretty fine piece of design despite its unexotic nature.” For the record, CW’s editors confirmed bike weight, with half a tank of fuel, at 241 pounds, and the 1967 Kit America’s price of $389.

Migrating to America

As you might guess, the TSS racers and kitted Metralla Mk Il became popular among American road racers back in the 1960s and early 1970s, and today surviving examples are scattered among the starting grids at AHRMA and other vintage-based events. Two such Bultaco survivors, a TSS 250 hybrid and a converted Metralla Mk II, are currently enjoying redefined lives in Southern California where sportsman Roland Ortiz exercises their piston-port engines at closed-course track days and select AHRMA races. And, in upstanding vintage-bike tradition, the bikes boast their own provenance and composition.

First the provenance, which is what partially led to how and why Roland obtained both bikes from the stable of former AHRMA veteran racer Pete DeRosa, who himself enjoyed a respectable amount of success competing in the 250 GP class. Unfortunately, failing health a few years ago prompted Pete to sell his two bikes, and that’s where Roland enters the picture.

“I bought the bikes from Pete about three years ago,” says Roland. “I got a call from Bultaco specialist Lynn Mobley; he told me that Pete DeRosa was ready to sell his two race bikes and wanted them to go to a good home. Lynn knew that I would take good care of the bikes, and keep them on the track.”

So, after arranging a visit, Roland drove to Arizona to meet with Pete. “I spent several hours with Pete going over the bikes, and he shared his race stories with me from back in the day. Pete wanted to make sure that the bikes would still be ridden by whoever bought them,” recalls Roland in a nod to Pete’s eternal enthusiasm as a racer.

The TSS replica also now wears a Mikuni carb in place of the original Amal (top). The cool Menani magnesium front drum brake (bottom)..

Various track days, coupled with the annual AHRMA event at nearby Willow Springs Raceway, have helped Roland stay true to his words. Roland also paid tribute to Pete’s old racing number 49 on the kitted Metralla.

“I kept the 49 number,” touts Roland, “and added the R to my AHRMA number [49R].” For the time being, though, the TSS-based bike proudly wears number one, and is limited to track days for now.

Roland points out that engines on both bikes were originally prepared for racing by Scott Clough, a former road racer who made a name for himself on the Southern California club circuit back in the 1970s riding Yamaha RD350s that he tuned. After acquiring both bikes from Pete, Roland simply freshened up both engines’ top ends, leaving the port timing to Clough’s proven specs. Adds Roland, “If they were fast enough for Pete, they certainly were fast enough for me.”

The same, only different

Roland’s TSS model is actually a replica based on a replacement TSS frame, which, along with a wealth of other components, are available today thanks to specialty companies such as the Romero Motos (romeromotos.com) and AJR Motorcycles (ajrmotocicletas.es) in Spain. Looking to race your own TSS Bultaco? Try either of these companies for parts, and don’t necessarily expect a mirror-image replica when you’re finished. Bultacos were made for racing, and as with any race motorcycle, things change, and often for the better and faster.

To the trained eye, Roland’s bikes sport several noticeable differences when compared to authentic TSS- or Kit America-bred Bultaco racers. For instance, gone are the finicky 1960s-era Amal carburetors, replaced with 1970s-era round-body Mikuni mixers that are easier to tune and more reliable in performance during the heat of combat.

Owner Roland Ortiz gives us the Bultaco thumbs-up seal of approval.

While both bikes retain classic-looking drum brakes, none of the binders are necessarily original Bultaco ware. The Metralla relies on a pair of, what Roland describes as “recycled Japanese brakes front and rear.” The TSS replica’s rear brake is of similar Japanese origin, while the front is an attractive Menani magnesium fixture. Both bikes have Ceriani forks, something you’d expect to see back in the 1960s, while tires are newer Dunlop/Avon front and rear combinations that offer plenty of grip, especially considering the TSS’s laughable overall weight of 201 pounds. The converted Metralla weighs slightly more.

Both packages proved suitable for keeping Pete DeRosa at the forefront in 250 GP AHRMA races when he competed on them, and the little 2-stroke racers currently allow Roland to enjoy himself and to test his mettle at various race tracks in the Southern California proximity. They also represent two of Roland’s favorite classic bikes in a private collection that shares space in his garage and living room. Yes, living room, and that’s where the TSS and Metralla racers, along with several other front-line representatives from the 1960s, can be found in between track days and AHRMA races. As for the bulk of his collection, you’d be spot on if you guessed that most of it is composed of Spanish bikes powered by single-cylinder 2-stroke engines. MC

Bultaco TSS 250 replica

Engine: 244cc air-cooled single, 72mm x 60mm bore and stroke, 38hp @ 9,500rpm

Top speed: 131mph (period test)

Carburetion: Single Mikuni (original 30mm Amal 389 GP)

Transmission: 5-speed, GP clutch

Electrics: Femsa electronic ignition

Wheelbase: 51in (1,275mm)

Suspension: Ceriani 35mm telescopic fork, Works Ultralight shocks

Brakes: Menani magnesium 9in (235mm) drum front, recycled Japanese rear

Tires: Dunlop 2.75/3.75 x 18in KR823 front, Avon 110/80-VB18in rear

Weight: 201lb (91kg), period test with half tank

Price then: $1,245

Published on Oct 15, 2020

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