four stroke engine

I stared at this GIF explaining how a four-stroke piston engine works for far longer than I care to admit.

One day you’ll have to explain to your kids that this is how we powered our cars. I imagine they’ll be all: “Whaaaa? You used the combustion of aerosolized dinosaur extractions to drive your car? The old days were weird, mom/dad.” (they will text you that of course, from their Google Glass).

Defunct German Car Brands: Lloyd

Lloyd is a defunct car brand from Germany that belonged to the Borgward group, which went bankrupt in 1961. After world war II, Lloyd specialized in small and cheap cars, which required a lot of compromise from their owners, but were much in demand in post-war Germany.

The first model, the 300 series from 1950, had a body made from wood and steel covered with leatherette mounted onto a steel frame. The leaterette was prone to develop cracks, which the owners repaired using adhesive tape, so the car was nicknamed “Leukoplastbomber” (Leukoplast is a brand of sticky fabric tape). The whole construction was absolutely unstable in case of an accident, so a saying went “Wer den Tod nicht scheut, fährt Lloyd” (Who is not afraid of death drives a Lloyd).

The concept of the drive train with the engine mounted transversally in the front, driving the front wheels was exceptionally advanced for its time. It was very similar to the unit developed for the East German Trabant – no wonder since the developing team of the Lloyd unit consisted mainly of refugees from East Germany.

However, the tiny 300 cc air-cooled two-cylinder two-stroke engine developed only 10 hp, making the car dramatically underpowered. A saying went “Der Lloyd steht am Berg und heult” (”The Lloyd stands at the foot of the mountain, crying”). Over the years, the engine was improved and increased in power.

As Germany became more and more wealthy, the Lloyd was upgraded, receiving stronger engines and a steel body that included a rear hatch for the trunk (before, the backrest of the back seat had to be folded down to access the trunk).

When the new driver’s licenses were introduced in 1956, an even more reduced model with a 250 cc engine was sold. It was marketed for people with an old driver’s license valid for vehicles with an engine up to 250 cc, who shied away from having a test for the regular car license.

In its last incarnation, the car was named “Alexander” and had a 600 cc two-cylinder four-stroke engine.

After the bankruptcy of the Borgward group in 1961, the two-stroke engine was kept in production and was mostly exported to the US and Canada, where it was popular to power snow mobiles.

The demand for tiny cars faded away by the end of the 1950s and people desired bigger models. Lloyd responded with the brand new Arabella in 1959. Initially, the car was planned to be powered with the engine of the Lloyd Alexander; however, the car proved to be underpowered. A new flat-four engine with 900 cc was created at the last moment – and was the cause of severe teething problems of the early models. The gearbox taken over from the smaller Lloyd Alexander was unable to cope with the power of the bigger engine and was prone to fail. Additionally, the body tended to leak water, earning the car the nickname “Aquabella”. The resulting slow sales of the model, which was intended to be sold in masses, contributed to the financial struggles and eventual bankruptcy of the Borgward group.

Lloyd also had a small van in its portfolio, being powered by 13 or 19 hp two-cylinder two-stroke or four-stroke engines.

(ABOVE) A one-cylinder alcohol fueled Perreaux engine, which used twin flexible leather belt drives to the rear wheel. A steam pressure gauge was mounted in the rider’s view above the front wheel, and steam to the cylinder was engaged and regulated with a hand control. -CIRCA 1872

(ABOVE) The Hildebrand & Wolfmüller patent of 1894 describes a 1,489 cc (90.9 cu in) two-cylinder, four-stroke engine.

(ABOVE) Glen Curtiss’ V8 machine, on which he became the ‘Fastest man in the world’ for over 20 years. In 1903, he set a motorcycle land speed record at 64 miles per hour (103 km/h) for one mile (1.6 km). His first motorcycle’s carburetor was adapted from a tomato soup can containing a gauze screen to pull the gasoline up via capillary action.

(ABOVE) Mark Walker is inspired by the builders of the turn of the century. This 2013 Supercharged 2 stroke V16 is called “1916”


~Steampunk Love •❀• From Airship Commander HG Havisham


Hammacher Schlemmer released a 1:5 scale Jaguar XK120 Mini Roadster made for adults. The roadster is powered by a 110cc four-stroke air-cooled engine that provides a top speed of 38 mph. Price tag: $21,566


Defunct German Car Brands: Trabant

Trabant was an East German car brand deeply rooted in the pre-war car industry of Saxony.

Before world war II, Saxony was one of the centers of the German car industry, featuring brands such as Wanderer, DKW, Horch, and Audi, which together formed the Auto Union. After the war, the production facilities were in ruins, and what was left was seized by the Russians. The carmakers had a difficult start, which was not eased by the fact that they were immediately socialized and directly controlled by the government. Many engineers went to West Germany, where they were either hired by Borgward, where they went on to produce the tiny Lloyd microcars. Others went to Ingolstadt, where DKW had a central warehouse for spare parts, to form a company independent of the East German roots. (That company later became Audi.)

The remaining engineers struggled to set up a production line for the pre-war models DKW F8 and DKW F9. Of the latter model, only prototypes had been built before the war, but it had never been put into in production in favor of war-related vehicles.

Others developed a stylish, expensive luxury sedan in the tradition of Audi and Horch, named Sachsenring P 240 featuring a 2400 cc straight-six engine.

However, both cars proved to be too expensive and unsuitable for mass motorization, which the government believed could only be achieved with a unified cheap small car. They ordered the engineers in Zwickau, Saxony, to develop a microcar using as much as possible existing pre-war technology. Bubble cars like in West Germany were deemed unsuitable from the very start; instead, a proper little car was aimed for.

The first result was ready in 1955, but it was not yet called Trabant, but AWZ P70. It was based on a shortened chassis of the 1939 DKW F8. It had the same water-cooled longitudinally mounted 700 cc two-cylinder two-stroke engine, which produced 22 hp. However, the water cooling was of a thermosiphon type and the placement of the radiator behind the engine instead of its usual place in the front caused the engine to overheat frequently. This triggered the development of an air-cooled variant of the engine used in the later Trabant.

The body was also a novelty: A wooden space frame was covered with a newly developed plastic made from recycled material. This material called Duroplast was a phenol resin reinforced with waste cotton fibers from Russia. The engineers had to come up with such an exotic and novel solution because high-quality sheet metal from Western Europe was embargoed, the Russian steel was unsuitable, and own East German steel production capacities were not yet existing. This emergency solution made the AWZ P70 the first car using recycled plastic. The roof was made from plywood covered in leatherette, as the Duroplast technology was not yet developed far enough to produce parts of that size.

The spartan equipment made the car unattractive. All windows were fixed, the trunk did not have a lid and had to be accessed by removing the backrest of the rear seat. These issues were later corrected.

A station wagon popular for its huge capacity and a coupe with all-steel body, which was internationally acclaimed for its sporty design, were added in 1956 and 1957, respectively.

The car turned out to be too costly in production and to be plagued with too many issues to be the basis for mass-motorization. Production was stopped in 1959. The experiences made with this car went into the development of the Trabant P50, which appeared in 1957.

Duroplast technology was improved, and a new 500 cc 18 hp air-cooled teo-cylinder two-stroke engine was developed to avoid trouble with the water cooling of the predecessor. The wooden space frame was replaced by a steel unibody. By the time the car made it to the market, it was among the most advanced microcars, providing relatively comfortable seating for four adults and a large trunk with a usable size of 415 liters (110 gal). This was enabled by a clever arrangement of a transversially-mounted engine and gearbox unit over the front axle, which required minimal space for the driving unit.

A station wagon was introduced shortly after the sedan.

In 1962, the engine was enlarged to 600 cc, resulting in an increas in power to 23 hp. The bodywork remained unchanged. The car was renamed to Trabant 600.

The last big change for a long time came in 1694, when a new body replaced the dated 1950s design for the model Trabant 601. The outer panels were still made from Duroplast, earning the car the nickname “Rennpappe” (”racing cardboard”).

The station wagon was also redesigned.

In this shape, the car was produced with only minimal changes and improvement for the next 26 years. Over the years, power outpot was increased from 23 to 26 hp. Design and technology, which were apart from the two-stroke engine still contemporary or even advanced by the time the model appeared, became more and more outdated, and although the car was reliable, it acquired a bad reputation and became an icon of the backwardness of the socialist economic model.

The engineers in Zwickau designed several potential replacements, experimented with Wankel engines, built prototypes, but all in vain. The political leaders personally stopped all plans, fearing unnecessary investments as the car was working well and the socialist citizen did not need luxury.

Despite all shortcomings, and weaknesses of the ageing construction, production never met the demand, and potential buers had to wait for up to 20 years to get a new car. It was common that parents signed a contract for a child right after it was born, expecting the car to be delivered well after its 18th birthday. This was mostly due to the cumbersome and slow production process of the Duroplast body panels.

In the late 1980s, East Germany acquired a license to produce engines for Volkswagen, who expected a cost advantage from the cheap production in East Germany. Part of the agreement was that a certain contingent of the engines produced would be for the local cars, Trabant and Wartburg. However, investments for the new production line exploded, so no money was left to develop a new body for the car. Using many makeshift solutions, the old body was adapted to accomodate the 1100 cc version of the new, much bigger four-cylinder four-stroke engine. The result was an excessively expensive small car with an outdated body that was probably even more unpopular than the original in its final years. In 1989, when the car was introduced, the peaceful revolution in East Germany and the reas of Eastern Europe was in full swing. Production started in 1990 and ended already on April 30, 1991, after only 12 months. With the financial, economic and social revolution in July 1990, western cars became affordable for the East Germans, and the Trabant had no chance for survival. Even price dumping, offering the car for only 6,000 DM (instead of 16,000 DM) did not help sales.

Many Trabant cars were abandoned after the owners had acquired a new western model. They created a major waste problem as the Duroplast was almost impossible to recycle.

Today, Volkswagen is present in Zwickau with a factory, and many suppliers are also producing there. However, they do not require as much workforce as the cumbersome and labor-intense production of the Trabant did, creating an unemployment problem in the region and a massive decrease in population.

Today, the car has achieved a kind of cult status. It has become a symbol of the German reunion, when tens of thousands of little Trabants were flooding into West Germany the days after the wall fell.

Defunct German Car Brands: DKW

DKW was a brand that was founded in Chemnitz, Saxony, in 1904. The original plan to develop steam cars (Dampfkraftwagen) never materialized.

Instead, they mass-produced a toy engine developed by Hugo Ruppe, a brilliant engineer with no sense for business. DKW developed a successful advertising campaign, naming the engine “Des Knaben Wunsch” (”The Boy’s Desire”). It was a hit-seller.

Simultaneously, they developed, enlarged and improved the little two-stroke engine to make it suitable to be mounted on a bicycle as an auxiliary engine. The DKW marketing experts worked out a catchy slogan utilizing the three letters DKW once again: “DKW, das kleine Wunder, / fährt bergauf wie andere runter” (”DKW, the little wonder, drives uphill like others do downhill”). The engine became another success.

Encouraged, the company started to develop proper motorcycles, which, with good help from the marketing department, sold well. The model RT 125 was particularly successful and was copied worldwide by other manufacturers. It is still today the motorcycle with the highest production numbers.

As the demand shifted more and more from motorcycles to cars, the company began to develop small, light-bodied cars, which could be powered by the enhanced two-stroke motorcycle engines. The resulting F1, first introduced in 1930, became the first mass-produced car with front wheel drive. From there, a straight line of development began until after world war II. In 1932, DKW merged with Wanderer, Audi, and Horch, all in financial struggles from the world economic crisis, to form the Auto Union group, symbolized by the four rings.

When Germany was divided, many engineers from the Saxony-based Auto Union went to West Germany. Some were hired by Borgward, where they developed the superminis under the Lloyd brand, which were stunningly similar to the East German Trabant. Others formed a new West German Auto Union company based on the central spare parts depot in Ingolstadt, Bavaria. Full production was started in a former arms factory in Düsseldorf.

The first model called F89 Meisterklasse was entirely based on pre-war technology. The bodywork was from a never mass-produced 1940 prototype called F9. The frame, drivetrain, and suspension came from the tried-and-tested F8. It featured a transversally mounted water-cooled two-cylinder two-stroke engine driving the front wheels. Performance was meagre as the heavy bodywork was designed to be propelled by a more powerful three-cylinder engine.

The upgrade to a longitudinally-mounted three-cylinder engine finally came in 1953 with the F91 Sonderklasse, using more or less the same body, but the more advanced frame and suspension of the dropped F9 project. To boost sales, the DKW marketing department sprang into action. They changed the name from “F91 Sonderklasse” to “3=6″, claiming that the three-cylinder two-stroke engine would run as smooth as a six-cylinder four-stroke engine. This claim was hammered into the carbuyer’s brain in a massive year-long advertising campaign, so it was still present in the collective memory decades after the brand (and two-stroke engines) had disappeared from the West German market.

In 1955, the bodywork was slightly revised and the engine enlarged. The car was now marketed as “Der große DKW 3=6″ (”The big DKW 3=6″) with the internal model number F93. However, it became more and more obvious that the car with its pre-war design and smoky two-stroke engine was dated. Against all ad campaigns, the car did not sell well, and Auto Union was unable to generate enough financial resources to develop a new model. In 1958, Daimler-Benz acquired the company and marketed the car as Auto Union 900 (F94).

As a first measure to improve the car, the engine was enlarged once again to 1000 cc, the old body received a stylish panoramic windshield and abendoned the former suicide doors, the interior design was upgraded to match contemporary Mercedes-Benz standards, and rigorous quality control improved reliability. To improve the horrible emissions mainly caused by the need to mix the oil with the fuel, which was then left unburned and part of the exhaust gases, the cars received a separate oil tank with a dosage pump that mixed the oil with the fuel directly in the carburetor. This measure reduced oil consumption significantly, improving the emissions to some degree. The car was now sold as Auto Union 1000, but sales continued to drop. In 1960, not many people wanted to buy a new car that looked as if it was from the 1930s.

Around the same time, a rakish variants of the Auto Union 1000, a coupe and convertible in Baby-Ford-Thunderbird style were introduced. They were desirable cars screaming “Rock’nRoll” from every angle. But instead of having a powerful V8, it suffered from the dated two-stroke engine.

In 1959, the long-awaited new body was available, but first only with the low-power 750 cc engines. It was called DKW Junior. Once again, a heavy ad campaign promoting the contemporary aspects of the car helped boosting sales. However, the new oil-mixing apparatus proved to be unreliable. Especially in the winter, when the oil became thick, the engine was starved from lubrication, resulting in piston seizure. Expensive repairs on warranty further the reputation of the brand.

When the Auto Union 1000 with its pre-war body was finally discontinued in 1963, the new (slightly revised) body received the stonger 1000 cc engine and was called F11 and F12 for two levels of trim. The fact that these small cars were of Mercedes-Benz-like build quality, which was heavily advertised, certainly helped sales, but the outdated drivetrain technology meant that they were not a big success.

The final model, a mid-sized sedan called F102 was introduced in 1964. The old-fasioned frame-and-body construction was finally replaced by a contemporary unibody construction. But it still featured a three-cylinder two-stroke engine with a capacity of 1200 cc producing 60 hp. A 1300 cc two-stroke V6 engine with 80 hp was available on special request, but rarely ordered. Both engines were noted for their excessive fuel consumption and smelly exhaust. DKW tried to counteract the fuel consumption by installing additional springs onto the accelerator pedal, making it heavier to push down (a measure later copied by the East German carmakers Trabant and Wartburg). All advertising did no longer help; the time for two-stroke engines was over, and despite the fashionable, sleek design and exceptional build quality, the cars were almost impossible to sell. Production was discontinued by the end of 1965, less than two years after the model was introduced.

Auto Union was sold to the Volkswagen Group in 1964, who installed a four-cylinder four-stroke engine developed by Mercedes-Benz, which required slight alterations to the front of the car. To get rid of the old-fashioned image, the DKW brand was dropped, and the revised car was marketed from 1966 on as Audi 60, Audi 72, and Audi 75, depending on the power output of the engine. It became a good success and was the start of today’s successful upmarket Audi brand.

DKW had a small delivery van (Schnellaster) in its portfolio, which was also available as a mini van. Initially, it was powered by a 2-cylinder two-stroke engine producing 20 hp, allowing for a top speed of 60 km/h (37 mph). Power was upgraded over the years, and finally the van received the 900 cc 32 hp three-cylinder two-stroke engine for 80 km/h (50 mph). The improved chassis of the DKW delivery van, which had been the basis of the Mercedes-Benz MB100, is still in production in China, providing the underpinnings of the SAIC Istana.

Pizza Pocket Because it just looks that much cooler than carrying a pen in your front left pocket. Pizza Car Freshener Why can’t your car ALWAYS smell like you just brought a pizza home? Pizza Cheese Clippers Sometimes teeth just can’t do the trick. Gas-Powered Pizza Cutter It has a four-stroke, two-horsepower engine and a steel-alloy cutting blade. You know, in case you want to douse your walls in marinara sauce. Pizza Mints Perfect for a first date!