Royal Enfield Turbo Twin

In July 1961 the UK motorcycle learner laws required manufacturers to take the 250cc market seriously, so in 1964 one manufacturer all about the past offered a model with its name embedded in the future.

Royal Enfield – Turbo Twin Sports

‘'As smooth as a 60’s Crooner’

This models futuristic name was an unusual choice for the Redditch based company as the phrase ‘turbo’ was not very common in the early 1960s. Just one year prior to its arrival Chevrolet and Oldsmobile produced the world’s first turbocharged production cars; maybe this influenced the decision? Alternate opinions consider the name promotes the silent, super smooth, almost turbine like power delivery offered by the rubber mounted Villiers motor. Whilst Royal Enfield’s history is rich and colourful there is a modern biker generation who really only associate the name with Chennai, India, therefore it is worth pointing out that over the years Royal Enfield produced bikes from five locations around the UK including one 90ft underground in Wiltshire. With a nine bike range on show at Earls Court in 1964 and with Geoff Duke OBE extolling the virtues of the marque to the masses on stand 75, surely this should have been a prosperous time for the Company; unfortunately it was the beginning of the end.

Prosperous Past

Similar to BSA the Royal Enfield brand was first and foremost a manufacturer of weapons that began to produce bicycles from 1893; their first vehicles in the form of trikes and four wheels arrived just prior to the turn of the century. Motorising a cycle in 1901 lead to the development of their first motorbike, the Model 180 in 1912 and that showed the company’s potential with innovations such as the two speed gearbox and a chain drive with the world’s first rubber ‘cush hub’. A second version featured a smaller V twin engine at 425cc which benefited from an automatic oil pump, overnight resigning the old manual operated version to obsolete. Royal Enfield continued to expand, especially during the war years, taking large Government contracts to supply both cycles and motorbikes to the army during the 1914-18 conflict. World War 2 and the factory released some 55,000 machines to the Allied effort mainly from their bomb proof underground factory in Westwood Quarry, Wiltshire. Nicknamed ‘The Cave’ this secret establishment continued to produce motorbikes until the late 1960’s. Post-war and more innovation followed with the rear swing arm suspension, this wasn’t just more sophisticated than anything prior but also led to domination in trials competition when their new 350 Bullet was paired with the talented Johnny Britain; a combination that ruled the sport for nearly a decade.

The Turn of the 250’s

Late fifties and into the sixties the 250cc market was becoming worthy of investment for all manufactures and the Crusader range offered much, unit construction, Villiers power plants and a sports version but it was their Continental GT that would become a firm favourite. In 1965 the GT could outperform Enfield’s rivals and offered real café racer looks and a 5 speed gearbox; a real ‘head-turner’ on the North Circular Road no doubt. The original ‘Bullet’ range was disappearing from the sales floors (in the UK) and with little to replace it, the onus and investment transferred to the learner legal/250cc market; just the Interceptor remained flying the flag for the ‘big twins’. Geoff Duke joined the company in 1964, his task to re vitalise 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.

A Brilliant Bitza?

Villiers 4T two stroke motor arrived on the scene in 1963. It was very similar to the 2T launched in 1956 but featured an extra pair of transfer ports and ported pistons offering higher compression. 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’. A low 29in seat height catered for the more vertically challenged but the ride isn’t too cramped for those taller and reasonable progress can be made as long as the Villiers unit is kept ‘buzzing’. One thing that was noted by publications in the sixties was how quiet the bike was on the move, with the silencers designed especially for the 4T the muted tone remains today. The 17in wheels enjoyed 6in diameter brake drums front and rear, adequate for the time but maybe slightly under whelming on today’s roads; all taken from the Clipper model. 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. The suspension was considered firm for the time but that added to the sporty feel, so it was of no surprise that the Turbo Twin Sports model arrived in 1964. 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 - genuine value for money that lead the way in the twin cylinder two stroke field’. The price was right at £20.00 more than the existing machine; £215.00 including taxes got you on the road with a Sport.

One Man Many Machines

A small strip of land, some eight miles long, reaches out into the Channel; it’s about as far south as England reaches and is known as the Manhood Peninsula. At the tip sits the small town of Selsey, often threatened by the incoming sea it is home to quite a few classic characters, especially lifelong biker Derek Carter-Hammond. Being perched on a 1939 Norton for a family photo certainly had an effect on a pre-school Derek who began biking as soon as legally allowed, if not slightly prior. ‘My first machine was an NSU Quickly, followed by a Lambretta LD150 but I fell off that within a week’ my host informed me. He then purchased a Triumph T21 350cc and barely a day has passed in this man’s life where he hasn’t enjoyed two wheels. ‘These bikes weren’t classics back then’ he continued ‘but now looking back, like most folk I wish I had kept just a few of them’. His garage currently features a 500 Bullet, BSA C11, Flying Flea and a 1936 Excelsior Meritor plus a Hinckley Triumph. The Turbo Twin belonged to a great friend and fellow Sussex British Motorcycle Club member Don Noble. ‘When he passed away his collection found new custodians and I was lucky enough to purchase the Sport’. Five owners from new and with an engine rebuild back in 2009 the bike was pretty much up and together and having been regularly ridden by the previous owner Derek continues the tradition. ‘It’s not concours but I do like to ride and whilst I would never thrash any of my machines, they do get a workout whenever the chance presents itself’. Suitably attired Derek wheeled the Turbo Twin Sport out and on the third kick the familiar two stroke note filled the air, along with a blue haze. ‘The choke is a terrible idea’ he pointed out. Activated by a plunger on top of the Villiers carburettor, push down for choke on and pull up to switch off; impossible when moving, the rider is forced to stop once the engine has some heat. I followed the blue haze through the country lanes and over a coffee break I enjoyed an honest opinion of Enfield’s Sport from the owner. ‘The front brakes aren’t brilliant but the rear is very good, the forks are adequate and overall the bike handles really well but ‘rider beware’ the centre stand scoring tarmac’. ‘A comfy seat that is ok for a few hours riding even at my age and with such a big fuel tank on a small bike less pit-stops are needed. The clutch is light and the gearbox positive even by today’s standards making the bike relaxing to ride even if the Ace drop bars eventually get to your wrists. Running the Avon Speedmaster tyres works very well with this bike in any weather and there is little to worry about with the electrics either, the headlight is better than a candle with a small on/off switch, whilst the horn and dipped beam are operated via the handlebar mounted control’. After spending a few hours with the Turbo Twin I began to appreciate many of Derek’s points. A 1965 vintage two stroke that sounds almost silent compared to the far eastern oil burners that took control over the following decade. Ideal for the shorter rider and very light to manoeuvre for a fifty year old British classic, this Enfield buzzed around the countryside of Sussex with plenty of vigour. So what about the performance? Is Derek still able to get the most from his steed? ‘You don’t need to scream the motor to accelerate quite rapidly, keeping with modern traffic is easy but like the rider this old girl is comfortable with a max of 50mph, she will do more but like me doesn’t want too’. To conclude, this Royal Enfield model is a rare item nowadays; it offers a unique appeal, is easy to maintain and being light and agile is a pleasure to own, according to Derek. Tracking down a suitable example will require some patience, being great value transport in their day these machines would have been daily drivers. Although the model enjoyed just a three year production run, parts supply today is good and pricing remains sensible making this Enfield a good choice for a classic newcomer. Asking the man from Selsey if he would consider ‘selling on’ Derek confirmed that after a lifetime playing ‘Motorbike Monopoly’ this Turbo Twin Sport is a ‘keeper’.

Royal Enfield Turbo Twin Sport Specification

Engine: Villiers 249cc Mk 4T two stroke twin

Transmission: Villiers Four speed to rear of engine

Carburettor: Villiers S25 plunger type

Electrics: Lucas 6 volt

Fuel capacity: 3 ½ gallons

Weight: 298lbs

Performance: top speed 75mph/standing ¼ mile 21.6s

Fuel consumption: 96mpg @ 30mph/52mpg @ 60mph

Ground clearance: 5 ½ in

Royal Enfield Gossip

First World War fuel rationing saw the Enfield become the machine of choice for those looking to run their bike on coal-gas; often trailered behind a 6hp sidecar outfit in a huge balloon. One lady enthusiast had her gasbag fitted to a large tray above the occupants’ heads and whilst the engine power was reported as being unchanged the same could not be said for the aerodynamics of such transport.

Safe from German bombers during WW2 the Royal Enfield works at Westwood Quarry housed priceless art from London’s museums and Buckingham Palace alongside various motorcycles including ‘the Flying Flea’. The company’s engineers also supplied many wartime requirements including gyroscopic gun sights, armour piecing shells and stabilisers for search lights.

In 1982 The Times reported that the final assets of Triumph including the name would be sold to one of the two bidders that remained interested, the first being Cagiva, the other Enfield India.

Enfield Industrial Machines was purchased by Greek shipping millionaire John Goulandris who formed Enfield Automotive, producing a small electric car in the mid-sixties and set up a manufacturing plant in Cowes on the Isle of Wight. The IOW plant went on to produced a prototype 4x4 vehicle and off shore power boats under the Enfield Marine Division. The name continues today using a version of the famous gun logo providing electric guitars.