A childhood growing up close to a motocross track in southern Germany meant Michl Betz, now 43, developed a lifelong love of two-stroke motocross bikes. Combine that with a passion for Harley-Davidson and a select group of motorcycles remains.

The first bike to scratch the H-D two-stroke itch for Michl was a rare Harley-Davidson^® X90, a motorcycle from the ’70s, produced when the company was looking to draw in new riders with entry level two-stroke bikes. This bike proved to be a hit wherever it appeared and the quality of the restoration meant that the little X90 took a coveted first place in the Antique category at the European Bike Week^® custom bike show.

The X90 was followed up with the acquisition of an even rarer Harley off-road two-stroke – a 1972 Baja 100, designed to compete in gruelling desert races such as the Baja 500 –and then a Harley-Davidson SX250, a purely off-road competition bike. Competing on the SX250 at Harley & Snow in the south Tyrol, where riders have to complete a speed hill climb up a snow slope on spiked tyres, soon showed the SX250 didn’t have the power to compete with bigger bikes, even when fitted with a larger 350cc engine.

Purely by chance, parts of a 1978 Harley-Davidson MX250 became available and the SX was sold to fund the purchase. The MX250 is a full-on competition motocross bike made famous by the Harley-Davidson factory motocross team which competed in the 1978 motocross World Championship. Produced only for the 1978 model year and for the US market only, just 1,000 examples of the MX250 were produced and this rarity means the bikes are in high demand when they appear on the market. Just four examples of the model are known to exist in Europe.

With the MX250 in a dismantled state and consisting of little more than a frame and a few other items, a three-year project to source parts and reconstruct the bike to its original specification began.

In common with many competition-only bikes, parts for the MX250 are extremely rare; some items, such as the fenders, air box and the one-use-only shock absorbers are almost unobtainable. Michl managed to find an ultra-rare air box from a closed-down Harley parts shop, while the front triple trees came from a specialist in old Harley racing parts. The issue of the one-use shock absorbers was solved by installing discrete refillable gas reservoirs in the original items, a modification carried out by a German suspension specialist.

Some parts proved virtually impossible to source: the fenders are reproduction items and the cylinder head is an item originally fitted to a Cagiva RX250, near identical to the original but actually improved by the radial finning pattern. Michl managed to find eight of these in Italy, bought them all and used the remaining seven to trade for different MX250 items from other enthusiasts worldwide. A new-old-stock (NOS) front rim and spokes were purchased, but then tragically lost in transit, so the bike currently wears the hard-lived original rim until another NOS item eventually appears.

The MX250 represents a period of Harley-Davidson history when the company – at that point owned by American Machine and Foundry – decided to go motocross racing by commissioning their Italian-based subsidiary Aermacchi to build a competitive, lightweight 250cc motocross bike. By 1976 a hard-riding Californian named ‘Rocket’ Rex Staten was hired as lead rider and the factory team’s attempt at the Championships was ready. Although the MX250 achieved some wins, the championship itself proved elusive and the factory motocross team was dismantled after the 1978 season and the MX250 was discontinued.

Michl showcased the finished bike for the first time at the 2022 European Bike Week custom bike show, riding the bike onto the awards stage while clad in original and ultra-rare 1978 Harley-Davidson motocross gear. The bike took first place in the Adventure and Off-road category and the award was presented by Bill Davidson – who in a strange twist of fate revealed that the Davidson family owns the MX250 ridden by the highest place factory team rider, ‘Rocket’ Rex Staten.

Small but mighty
Harley-Davidson is now associated with large capacity V-twin four stroke engines, but the Motor Company has an illustrious history of two-stroke power as well.

Production of small capacity bikes ran from 1948 to 1966 to meet the post-war demand for inexpensive two-wheeled transport; the Hummer was introduced in 1955, followed in 1960 by the Topper scooter. Continued demand for two-stroke power led to the Motor Company purchasing a 50 per cent stake in Italy’s Aeronautica-Macchi to form the Harley-Davidson Aermacchi motorcycle division.

A series of Aermacchi-powered two-stroke models then followed through the 1960s and 70s, including the SS and SX250 and 350, the MX250, the Rapido and the Baja. Harley-Davidson purchased full control of Aermacchi in 1974 and continued the run of Italian-built two-strokes until the Aermacchi facility was sold to Cagiva in 1978, when Harley-Davidson two-stroke production came to an end.