Trials have been around since the earliest days of motorcycling, when manufacturers competed in what were then called reliability trials. These events were devised to ultimately test the mettle of new machines. As internal combustion engine and power transmission technology improved, the reliability part of the equation became redundant. Instead, the focus shifted to the building of specialized trials machines and furthering rider development. Regarding rider development, perhaps one of the best-known names in the sport of trials is Mick Andrews. And, perhaps one of the best-known makers of trials machines is OSSA — a Spanish-based motorcycle company. OSSA and Andrews joined forces in the 1960s, and a result of that partnership was a machine like the one seen in the accompanying photographs, a 1972 OSSA Mick Andrews Replica. This example is owned by Texas-based Ed Sass and was restored by Tom Willis.

The 250cc OSSA Mick Andrews Replica trials machine represents something of a legacy for Andrews. Aboard a small-bore street bike, Mick Andrews began experimenting riding offroad near his English home in the late 1950s. By the time he was 17, Andrews was competing in trials events aboard a rigid-framed, 2-stroke-powered James. He then moved on to a 4-stroke, 350cc Matchless and his talent was noticed by AJS competition manager Hugh Viney. In 1961, during Andrews’ first competition on an AJS he beat well-known rider Sammy Miller, thus proving himself a competitive force on trials courses.

The air cooled 244cc 2-stroke single puts out 19 horsepower at 6,500rpm.

The move to OSSA

After AJS, Andrews rode for Bultaco, then became a factory rider for OSSA. Formed by Manuel Giro in the early 1920s, Orpheo Sincronic Sociedad Anónima, or OSSA, was a company that initially built theatre film projectors and other equipment. But Giro, who had been a merchant marine, liked to go fast across water and constructed some of his own engines and watercraft to pursue the sport.

According to ossaengineering.com, by the early 1930s it was the call of road racing that spurred Giro to purchase and campaign a single-cylinder 500cc Norton. He moved on to a BMW but found the 500cc twin-cylinder bike still lacked the power he desired. So, he installed his own 1,000cc 6-cylinder engine from his boat racing days in the frame of the BMW, only soon to discover that while fast in a straight line, the machine was a bear in the corners. To fix this, Giro installed a sidecar and became a champion sidecar competitor.

The kickstarter is on the left.

Motorcycles were never far from Giro’s mind, however, and after World War II, when Spanish citizens were clamoring for inexpensive and reliable transportation, he saw an opportunity to introduce a small-bore machine to the marketplace. OSSA launched its first motorcycle in 1949. It was equipped with a 125cc engine and 3-speed transmission. More advanced models soon followed, along with a 50cc moped.

Eduardo Giro, Manuel’s son, became an engineer and by 1965 was OSSA’s director of development. That same year, he managed to gain OSSA great fame after the company campaigned two 175cc racing motorcycles at the 24 Hours of Barcelona, beating Bultaco and Montesa. Competition machines, and many racing victories, helped OSSA sell beyond just the Spanish market. However, the firm withdrew from road racing after their four-time 250cc Grand Prix winner Santiago Herrero crashed and died in 1970 at the Isle of Man TT. After that, OSSA seriously turned their attention to motocross, enduro and trials pursuits.

Trials specialist Mick Andrews, who had been collaborating with the company as early as 1966, brought OSSA top honors in 1971 and 1972 in the European Trials Championship. From 1970 to 1972 aboard an OSSA, Andrews also won the Scottish Six Days Trial.

The single Mikuni VM24 Carburetor.

The Replica

OSSA’s Mick Andrews Replica was built between 1972 and 1978 and is a lightweight, lithe and trim package that weighs just 197 pounds without gasoline. Motivation comes from a 244cc single-cylinder, single port 2-stroke engine mated with a 5-speed constant mesh transmission with chain final drive to an 18-inch rear wheel. Twin shocks suspend the swingarm, while the 21-inch front wheel with its diminutive 5-inch drum brake is held in a set of lightweight telescopic forks.

Engine and suspension components are bolted into a double-loop steel tube frame, topped with a fiberglass gas tank, minimalist side panels and a small pad for a seat. Fenders are aluminum, and there isn’t much else that makes up the Mick Andrews Replica. OSSA was set to launch the Mick Andrews Replica in 1971, but a flood at the Barcelona factory delayed release until 1972 — making Ed Sass’ a first-year example.

The large rear sprocket.

Ed’s been into motorcycles since he was a teenager riding a 1958 Allstate to high school. That was followed in college by a 1967 Triumph T100C. He loved to ride the trails, and although he’d take the Triumph offroad, his favorite bikes were lightweight Hodakas and Pentons. Bikes were left behind until the early 2000s, and he’s since been accumulating many of the British motorcycles that captured his interest when he was younger. He also has a collection of British cars, but still likes to pursue riding off the beaten path. Taking that a step further, he wanted to compete in the dirt.

“At my age, though, I didn’t want to go out moto-crossing or flat-tracking,” Ed explains. “I thought it would be somewhat safer to get into trials riding. And, because in my opinion there’s nothing as classy as a vintage Spanish-built machine, I wanted to find something like a Bultaco or an OSSA.”

Enter Tom Willis of Palestine, Texas. Tom grew up in Bartlesville, Oklahoma, and started riding in 1969 on a Honda Super 90. That bike was purchased in a box, and Tom assembled it and has been riding ever since, including motocross in the early 1970s, followed by a lifelong affinity for trials. He’s also an avid street rider.

Tom says he’s not a mechanic but enjoys restoring old machines. To his credit are several BMWs and even a Vincent café racer. Also to his credit are many Montesa and OSSA trials bikes, and he acquired this 1972 Mick Andrews Replica as a basket case in a trade. “It was mostly complete, but the bike had the greasiest engine I have ever seen,” Tom tells us. “But under all that grease was the best set of cases I have ever owned. No scratches, no dents. Perfect cases. It was way too good a bike to part out, so I got Jay Huffman [of Huffman Vintage Motorcycle Restorations in Donie, Texas] to help me do a total rebuild of the engine.”

Tom upgraded the engine with a beefier connecting rod from a Yamaha, a conversion that was sold in kit form via OSSA World. No longer in operation, OSSA World parts are now sold through vintco.com. Included in the kit was a crankpin and high-performance big end bearing and an improved piston wrist pin bearing.

A new piston, rings and wrist pin, main seals, countershaft seal, clutch pushrod seal, shifter seal, gasket set, main bearings and gear shaft bearings also went into the OSSA engine. Everything was tightened up with a new set of case bolts, and a fresh NGK B8ES plug threaded home in the head. A Mikuni VM24 carburetor with fresh rubber intake manifold adaptor was installed, as were Barnett clutch plates.

Ed sass aboard his OSSA.

Tom says the finished engine sat on a shelf for a year before he continued working on the restoration. “I built it to be a rider,” Tom says of the OSSA. To that end, everything Tom had was completely disassembled, including forks, hubs and brakes. All hardware was sent for zinc plating. The OSSA Mick Andrews Replica came stock with aluminum rims and stainless steel spokes. These were straight, so Tom simply polished all of the components and repacked the stock bearings with fresh grease.

“Trials bikes don’t have a lot of miles on them so unless the bearings were dry or abused they are good to repack with grease and go,” Tom notes.

Levered onto the finished wheels were Dunlop 2-ply trials tires, with two rim locks on the rear and one on the front. The tires are softly inflated, with 5psi at the back and 5.5psi up front.

The bike wears plastic fenders, which stand up better to use than the original aluminum guards.

The fork tubes were in good shape with no pitting of the external hard chrome plating, so Tom simply inspected the internals and reassembled them with a new set of seals and some polishing of the fork legs. On the OSSA, many pieces were originally chrome plated, and Tom had the front axle and nut, rear brake pedal, clutch arm, header pipe and nut and several other small pieces rechromed.

The top engine mounts on the frame were broken. Tom welded them up and also widened the foot pegs by welding on extensions. Then, the frame, foot pegs, swingarm and sidestand were sent for powder coating at Road Toys in Deanville, Texas.

In his inventory of parts, Tom had a stock fiberglass tank that had been coated with a Caswell sealer kit and painted in the Mick Andrews Replica white and green together with a good set of side covers. Knowing the OSSA was going to be a rider, he set them aside for the project.

Because the original aluminum fenders are somewhat delicate, Tom says he fabricated a front fender bracket using 3/8-inch stainless-steel tubing and mounted plastic guards front and rear.

After assembly, Tom says the OSSA fired up without issue, but he decided not to keep the bike for himself. That’s when Ed heard the Mick Andrews Replica was for sale, and he bought the machine in November 2018.

“It’s really simple to start,” Ed says of his trials bike. “Turn on the gas, choke on and two kicks and it’s ready to go. The awkward part of this is the kickstarter is on the left side of the bike, so I stand on the left and kick with my right leg.”

Ed Sass and his 1972 OSSA Mick Andrews Replica.

After these photos of the OSSA were taken, Ed competed in his first trials, getting the bike dirty. But that’s exactly what was intended when Tom built the Mick Andrews Replica.

“You have to keep going,” Ed explains about the sport of riding trials. “It’s all about balance, being able to turn tightly, and having good control of the bike at very low speed. I’m still new at this, and I’m not yet getting the bike into position to be able to make my next move — but I’m learning, and it’s practice, practice, practice.” And, unlike most other forms of motorcycle competition, Ed concludes, “There’s absolutely no advantage to being fast.” MC