This is the story of a 1902 Laurin & Klement BZ. This motorcycle is believed to be the oldest running motorcycle in Hungary, and it has been restored into a lean, mean – and quite frankly – beautiful fighting machine.
Words: Rich Orriss
Photos: Zoltan Ocksay and Tamas Kalmar
Founded by two cycling enthusiasts, mechanic Vaclav Laurin and bookseller Vaclav Klement, Laurin & Klement produced its first bicycle at the Mlada Boleslav factory in 1895. The company built its first motorcycle in 1899 and went on to become one of the leading motorcycle manufacturers in Europe in the pioneering years of the 20th Century.
In 1902 Laurin & Klement released the BZ. It had a unique shape that was characterised by a swooping arc that clasped the tall 331cc motor. A cylindrical oil tank sat on top of the engine while a box section fuel tank was sandwiched between the legs of the rider (where else would you want it!). An evaporative carburettor system and a low-voltage breakaway ignition were standard on the machines – these were the simple times, but the start of road for the motorcycle.
The BZ machines were deployed to compete in competition, and race specials were often equipped with water cooling to deal with the demands of the racetrack. For the most part however, the BZ was used to transport connoisseurs around the towns and countryside of Bohemia. In 1907 for example, Hungarian newspapers reported that Count István Csáky rode his Laurin & Klement for forty kilometres without a stop. Whether entirely accurate or not, it reflects how these early machines were perceived at the time – capable, but operating at the limits of reliability. In reality, machines like the BZ were difficult to use over any distance. Roads were poor, often little more than loose tracks, and traffic (often horse and cart, and the odd bit of cattle) was unpredictable. The motorcycle itself offered minimal braking, basic ignition, and a belt-driven rear wheel that could slip under load… but reliability depended as much on the rider as the machine.
For anyone that is used to the modern comfort of a push button motorcycle, an experience on a 1902 Laurin & Klement would be a bit of a shock to the system. The start-up procedure for a start is very much antiquated. The rider pedals the motor while the machine is on its stand, in an attempt to build adequate internal movement to foster combustion. It does take a relatively fit person to make this happen, but don’t worry – you don’t need to be an athlete! There is often a delay before the 331cc single-cylinder engine fires into life, and repeated effort is usually required before things start to fire into life.
An early attempt at fuel vaporisation is built into the design. In essence, a copper tube runs out of the exhaust and takes the warm fumes through the fuel tank to help vaporise the fuel – this was particularly relevant at the time that the BZ was built – fuels were heavy and this method helped ensure that fuel was vapourised before entering the cylinder. Clever stuff, and it helps save on the embarrassment of starting such an intricate machine in the modern day in front of an eager crowd with phone-cameras on the roll!
Once the motor cracks into action, it is time to ride the old machine, but remember that this bike was made almost 125 years in the past. As such, performance is modest. Around 30kph is achievable without too much of a problem, although higher speeds need to be treated with caution with the miniscule brakes. A band-operated front hub brake provides some resistance but was really there to signal intent rather than bringing the bike to a halt. In practice, riders often relied on their feet for additional control – thick heels helped when a boot was required to assist with a sudden stop! The controls on the BZ are equally as simple, including a decompressor lever and manual oil pump that delivers the golden stuff via a syringe mounted near the knee of the rider.
This machine was rediscovered in the 1990s by József Mokos, who found it in a sad state – incomplete and tired, with components such as the cylinder absent. This would be a serious project for a serious mechanic, and so the machine ended up with Tamás Kalmár. Considerable work was required. An original cylinder head was sourced and adapted, including the manufacture of a new aluminium piston.
The ignition system is a key feature on the BZ. Rather than using a spark plug, it relies on a mechanical make-and-break contact within the cylinder head. This system is sensitive to wear, contamination, and electrical leakage, and requires regular attention. By the 1910s, it had largely been replaced by more reliable high-voltage systems. This complex bit of kit (complex as it is completely abnormal in the world today) was rebuilt using period-correct components, including a Czech Bohemia unit.
Other parts had to be remade. The fuel tank was reproduced, mudguards fabricated, and numerous small components recreated. The drive belt was redesigned internally to improve durability while maintaining the original appearance.
Physically, the machine reflects early design priorities. The saddle is high, requiring a mounting technique similar to stepping onto the rear axle before moving off. Starting also depends on a non-standard chain, now reproduced in small quantities for early motorcycles.
Period details remain evident. Accessories include a carbide lamp, tool bag, and even a stick mounted to the handlebars – used historically to deter dogs. When riding through London in the modern day, this could come in handy!
In use, the BZ is demanding. As Kalmár notes, the lack of suspension and constant vibration can quickly lead to fatigue. Despite this, he rode the machine over 140 kilometres during a 2011 event, stopping frequently for fuel and ongoing adjustments. Maintenance included belt treatment and continuous monitoring of mechanical components. Braking performance, by his own account, is extremely limited.
The motorcycle has not been used in recent years and is now kept as part of a collection. Kalmár’s current focus has shifted towards American machines, particularly Indian, Henderson, and ACE, but every now and then the BZ is wheeled out into the sun.
The 1902 Laurin & Klement BZ represents an early stage in motorcycle development, before standardisation of components and controls. Its continued use is significant, not for performance, but for what it demonstrates about early engineering and the practical challenges of motorcycling at the time.
More than a century after it was built, it remains a working example of the experimental phase of the motorcycle – functional but requiring constant input from its rider to keep the wheels in motion.
an article by The Girder Club
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