Royal Enfield made twostrokes from as early as 1915 when the model series 200 started. At first there was only one type of bike, byt in the twenties there came several subtypes:
At first the model 200 stayed the standard model. The model 201 was the leight-weight and featured a kick-start from 1922 onwards.
By 1924 the model 200 became the sports bike, with a TT-like handlebar and footrest in stead of foot boards. The 201 was the light-weight and model 201A was a ladies model with a low step-through frame. These models still featured the Royal Enfield patented two gears with the two primary chains, but could now be operated by foot pedal. Model 202 was the light-weight with the 'old' hand gear change system and no kick-start. All of these models had a handlebar operated front brake, like they still use on push bikes, and a foot operated rear wheel brake, with a separate brake rim. Riding these bikes you have to use your boot soles a lot!
Starting 1925 all of the series featured the new internal expanding Enfield brakes on both wheels. The two-stroke engine was redesigned with two exhaust ports. They had a kick-start and a new type Enfield two-gears with handlebar controlled clutch.
By 1928 2 more types were added to the existing 200, 201 and 201A: model 202 and 203. These featured a new Enfield 3-speed gearbox, very different of the tw0-gear system of the other types. Both bikes had a saddle tank and an aluminium piston and aluminium detachable cylinder head. Model 202 is the standard model, while 203 is the sports model.
At the beginning of the thirties Enfield changed there model designation from numbers to letters. The series 200 became the model A. Still nearly the same 225cc engine that originated from 1915. There were two choices with or without elctric lighting.
In 1932 model A got a sloping cylinder, which was to be the look for the next six years. 1935 saw the engine loosing one exhaust port.
In 1939 model A's cylinder stood straight again with still one exhaust port and this was also the last year the 225cc was made.
Cycar Model Z
Production lasted from 1933 to 1936. The Cycar had a completely encased 148cc two-stroke engine. It was meant for people who did not want to dress in motorcycle wear, especially women and professionals like clergy men. The 3 speed gearbox is operated by hand shift.
Model X was only manufactured in 1934 and has a 148cc engine like the cycar. It featured two exhaust ports, but had a too small engine to atract much interest.
The original design of this motorcycle was by DKW in 1935, a 98cc 2-stroke known as the DKW RT100. In early 1938, the Nazi-German government instructed DKW to cancel its relationship with its Dutch concessionaire, R.S. Stokvis en Zonen of Rotterdam, after the Dutch company refused to force out its Jewish owners. In the Netherlands this DKW RT100 was a very popular light-weight motorcycle due to lower tax rates for motorcycles less than 60kg. (see the special regarding the Royal Baby)
R.S. Stokvis searched for a factory that could manufacture and deliver large enough numbers of small light-weight motorcycles on a very short term. They came in contact with the Enfield Cycle Co. Ltd. and simply took an example of the DKW RT100 to Royal Enfield. Technicians of R.S. Stokvis who had a lot of experience tuning the 98cc DKW engine for racing purposes designed a larger engine of 125cc with so called Typhoon fuel flow system. Royal Enfield's chief designer, Ted Pardoe, was responsible for the faithful reproduction of the DKW RT
Two prototype versions of the RE125 were displayed in Rotterdam in April 1939 under the name "Royal Baby".
A Dutch newspaper article of the 25th of April 1939 discribed this event and the bike as follows:
During manufacturing, the experience gained by the Stokvis company with those small motorcycles was amply utilized. For example, whenever there had been difficulties with certain DKW parts they were redesigned and replaced. There has also been searched for improved materials for all parts, so that weight savings are achieved, so that the definite product of "the Royal Baby" weighs only 48.8kg. Fully equipped, a motorcycle must weigh less than 60kg, so that the Royal Baby, including petrol, oil, mirror, horn, pillion, remains below that weight limit. The material used for the Royal Baby meets the highest demands.
The engine is a two-stroke block engine of 124.8 cc cylinder content, bore and stroke 53.8 x 55 mm. A so-called Typhoon fuel flush has been applied, so that the engine keeps running 2-stroke perfectly, 4-stroking does not occur. Lubrication is achieved by oil mixing through the petrol. A flywheel magnet of completely new design has been used. The flywheel does not have to be disassembled for checking points or cleaning. A special muffler is fitted, which effectively dampens the sound. The Royal Baby has a completely welded tubular frame with pressed steel fork. The gearbox in a union with the motor crankcase has a drive gear on ball bearings, the other shafts on silent bronze bushes. There are three gears with manual gearshift, freewheel and kickstarter. Furthermore, the machine has internally expanding drum brakes and Dunlop balloon tires 2.50 x 19. Undoubtedly, the Royal Baby is an interesting machine with clever technical details and a neat appearance.
The first two machines arrived in Rotterdam on the 12th of April 1939, delivery starts the first week of May, 100 machines are promised and they hope to catch up on orders in June, after which they can be delivered from stock.
World War II interrupted plans for civilian production after only a few were made and only a few were delivered to the Netherlands. We see this model with little change as model WD-RE in the second world war.
Model WD-RE or Flying Flea
In 1940 Mr. Churchil authorized the formation of a Special Air Service Battalion which resulted in 1941 in the Airborne Devision under general Browning. The parachute regiment was formed in 1942. The obvious need for transport on the ground resulted in numerously number of mostly BSA push bikes. The need for motorized transportation was at first provided by the Welbike folding scooter, but because of the small wheels was no success in rough terrain.
In 1942 there was a test of small two-stroke motorcycles. At the test a German DKW RT100 motorcycle was to be tested first as it was the lightest. The test proved that light-weight motorcycles were the solution for rough terrain. They could climb out of steep ditch with the help of some footwork, could easily carry 2 people and could be carried even over a fence.
The next step was comparing the DKW with its derivative the Royal Enfield 125cc, essentially a follow-up of the Royal Baby, resulting in the ordering of a prototype and an additional 18 bikes in 1942. The evaluation was so succesfull that it was followed by an order for 4000 WD-RE's for delivery of November 1943. At the end of the war nearly 7000 of the WD-RE would have despatched to the armed forces.
The wartime version of the Royal Baby was nicknamed the "Flying Flea" by the British Army Red Berets parachute regiment when it was released for service duty in 1943, where it was used extensively in airborne drops. The Flying Flea name fit perfectly, reflecting its light 130-pound weight and small overall dimensions; a mere 26 inches wide and 75 inches long.
After the end of the war Royal Enfield was not in a shape to start manufacturing new models quickly and started selling refurbished war machines returned by the army. A lot of post the post war two strokes were in fact refurbished model WD-RE's.
In 1947 production started slowly with polished pre-war designs, i.e. the model RE. It looked exactly like the pre-war Royal Baby in black with white striping but with a new style exhaust with integrated expansion part. The performance was about 3.5 brake horspower which gave a top speed of 45mph.
This continued until 1950 when model RE got a simple telescope front fork with two springs in two tubes. In 1951 a new model was introduced, the RE2 that performed about 4.5hp. 1953 was the last year of the 125cc model RE2.
In 1952 an additional Model the 150cc "Ensign", based on the R.E. came on the market. It had added power of the extra engine capacity, gave a performance of 5.25hp and a greater comfort provided by a kind of simple plunger suspension with springs. In both models, the engine and gear unit was identical in design, differences occurring only where necessary to accommodate the increased engine dimensions. Having no valve gear, the two-stroke power units were easy to maintain and, indeed, but little attention would be required by the entire machines beyond regular lubrication and periodic adjustment of the few points requiring it.
The Ensign had 3 sub-types, the first was followed by Ensign II and III. The output was increased to 6hp in 1952, the rear springs were hidden behind a cover and brakes and clutch were improved.
!959 another increase of performance to now 7.5hp for the follow-up model Prince which featured a swingarm rear suspension with telescopes. The prince looked like a real little motorcycle that had a top-speed of 55mph. Only two year, until 1961, the Prince stayed in the catalogues.
In 1963 no two-strokes were offered, but in 1964 a complete new design was presented, the 250cc Turbo Twin, Royal Enfields answer to the japanese two-stroke invasion. It featured the Villiers 4T twin engine with a higher compression ratio of 8.75:1 than the previous Villiers engines. With a four speed gearbox the unit offered 17hp and married to the Crusader frame Enfield hoped to produce a 70mph machine with great handling; early road tests confirmed they had achieved this. In fact, one publication confirmed ‘firm springing and low centre of gravity make bend-swinging a pleasure’.
The 17in wheels enjoyed 6in diameter brake drums front and rear, adequate for the time. Telescopic front forks and Enfield’s triumphant rear swing arm arrangement ensured this 300lb could be ridden with great enthusiasm, restricted only by grounding of the centre stand. Chrome finish to the tank and mudguards plus dropped handlebars came with the new model but as Geoff Duke confirmed ‘Whether your choice is the Standard or Sports model, you’ll be thrilled by the exciting new Turbo Twins'. It lasted only to 1965, when the Turbo Twin disapeared from the catalogue.
Geoff Duke joined the company in 1964, his task was to revitalise Enfield’s image and sales plus development control of their GP5 250cc programme. Unfortunately, just 20 of these race ready machines were built before funding became an issue; the project ceased as did the Duke’s involvement with Enfield in 1966.
And those were the last two-strokes build by the English Enfield Cycle Co. Ltd.
Enfield India however introduced the Sherpa in 1963 with a 175cc Two-stroke Villiers engine also made in India, incorporating a multi-plate clutch, four speed gear box and a robust and maintenance free chainstay. It was destined to take its rightful place in the motor-cycle world with a zestfull top speed of 90-95 km/hour.
In 1970 Sherpa was restyled and relaunched with the new name Crusader. Although the same Villiers engine was used for Crusader, major changes were made such as bigger brake drum, front fork and headlight the same as the Bullet. Indians sometimes called it the mini-Bullet.
But in 1980 Enfield India actually released a new model called Mini Bullet with a 200cc twostroke Villiers India engine. The model was intended as oposition to the Indo-Japanes twostrokes that came on the market. It wasn't a success.