Velocette Venom
 | |
| Manufacturer | Velocette |
|---|---|
| Production | 1955–1970 |
| Engine | 499 cc, OHV air-cooled single |
| Bore / stroke | 86.0 mm × 86.0 mm (3.39 in × 3.39 in) |
| Top speed | 100 mph[1][2] |
| Power | 34 bhp @ 6,200 rpm[1] |
| Brakes | drum brakes |
| Wheelbase | 54.75 inches (139.1 cm) |
| Weight |
390lb (177 kg) (dry) |
The Velocette Venom is a single-cylinder four-stroke British motorcycle of 499 cc made by Velocette at Hall Green in Birmingham.[3] A total of 5,721 models were produced between 1955 and 1970. In 1961 a production Velocette Venom set the 24-hour world record at a speed of 100.05 mph (161.01 km/h). It was the first motorcycle of any size to achieve an average speed of over 100 mph for 24 hours, and to this date no other motorcycle of the same capacity has been able to equal this world record.[4] In 1965, the Velocette Venom was further developed by Velocette designer Bertie Goodman to create the Velocette Thruxton, with a race specification cylinder head that was gas flowed by hand to accommodate extra-large valves and a downdraught inlet port. It was a very popular and successful clubman racer. However, although it had more power than the Venom, the Thruxton could not save Velocette.[3] Poor sales forced the company into voluntarily liquidation in 1971, with all the remaining stock and tools sold off to pay creditors.[5]
Development
Introduced in November 1955 and launched at the same time as the 349 cc Velocette Viper, the single-cylinder Venom was developed from the Velocette MSS and needed to compete against a new range of British twin-cylinder motorcycles. Conceived by Velocette’s Eugene Goodman and designed by Charles Udall, the Venom's 499 cc engine had a bi-metal cylinder with a cast-iron liner, high compression piston and a light alloy cylinder head. The design of the engine's high cam with short push-rods was simpler to produce than an OHC engine.[6] The Venom had high quality chrome plating and was finished in black paintwork with gold pinstriping. The Venom was also ahead of its time in being one of the first to have glass fibre–enclosure panels from 1960. These panels proved unpopular with the traditional buyers of Velocette singles,[7] as they extended from the front of the engine, level with the top of the crankcase, to the rear pillion footrests.[5]
An unusual feature of the Venom design is that the clutch was between the gearbox and gearbox sprocket rather than the conventional configuration in the primary chain case on the far left, with the gearbox sprocket between the clutch and the gearbox. This made the clutch less accessible but allowed for easy gearing changes and a range of sprockets with different numbers of teeth could be fitted by removing the sprocket cover. The gearbox was also a novel Velocette design with a constant mesh close ratio unit that could be maintained relatively easily while still in place.
Simply designed with single top and down tubes, the Venom's heavy brazed-lug frame (which had clear origins in bicycle manufacture) was well proven for its handling capability.[6] At the rear was an unusual swinging arm design with two arms in place of the traditional two prong fork. Although this was effective, it was complicated to set up the alignment. The rear shock absorbers were originally made by Woodhead Monroe, then replaced by Armstrong units and eventually Girling shocks. These could easily be adjusted to suit the rider's preference by moving them in special curved slots. The front telescopic forks (designed by Velocette and manufactured in house) had hydraulic damping and an offset wheel spindle.[5]
The Velocette Venom used Miller electrics up to 1962, with a belt-driven dynamo. After 1962 this was upgraded to a Lucas system. The speedometer, ammeter and light switch on the original Venoms were fitted into a steel headlamp nacelle the optional rev counter had to go on a bracket. Later models with Thruxton forks had conventional headlamp brackets and separate instruments.[5]
Eventually becoming the best selling 'flagship' of the Velocette motorcycle range, the Venom is now highly sought after as a definitive example of a British sports four-stroke single.[5]
Venom Scrambler
In December 1958,[8] the Velocette development team built off Venom off-road motorcycles which were sent to the United States for evaluation in enduro events.[9] Built to the Viper Clubman standard and advertised with the slogan 'A winner in every respect', the Scrambler had a specially lightened frame, light alloy mudguards and high-level enduro style exhaust pipes. A special off-road Venom was given the name the 'Endurance'. Fitted with the Venom engine, this had a 21-inch front wheel, high handlebars and a small fuel tank, as well as full lighting so that it could be legally used on the roads.[5]
Venom Clubman
From 1960, Velocette produced the Venom (and the Viper) in a 'Clubman' racing version, fitted with TT Amal carburettors, a manually controlled BTH racing magneto (in place of the Lucas unit) and a close-ratio gearbox, with the compression ratio raised to 9.3 to 1.[7] The Venom Clubman dispensed with the glass fibre enclosure and instead made a feature of highly polished crankcase and gearbox castings. Supplied with 'rearset' controls, lowered handlebars and a steering damper, the Clubman also had a range of optional accessories including a 'megaphone' exhaust silencer, a rev counter and light alloy wheel rims.[5] Although they could be hard to start (with a whole section in the owners handbook on starting technique) experienced Clubman riders found them easy to maintain and fast, as the Venom Clubman could achieve over 100 mph.[10] In 1966 the Venom was upgraded to the Mk II, which had the Thruxton front forks fitted with rubber gaiters, a twin leading shoe front brake and narrowed mudguards which combined with a new exhaust design gave it a more modern sports motorcycle look.[5]
Velocette Venom Thruxton
In 1965, the well-proven Venom was improved by Velocette designer Bertie Goodman with a special race kit complete with radically revised cylinder head, an Amal Grand Prix carburetor and reworked cam followers. The following year this went into production as the Velocette Thruxton. Also known as the Venom Thruxton, this aimed to fill the gap left by the demise of the BSA Gold Star and was named after the Thruxton Circuit race track on a former wartime airfield in Hampshire. The Velocette Thruxton was a true racer, with a full race specification cylinder head that was gas flowed by hand to accommodate extra-large valves and a downdraught inlet port. The Amal carburetor was so large it required a distinctive cutaway in the bottom of the fuel tank, and race cams boosted performance to up to 120 mph (190 km/h).[6] As well as the traditional black-with-gold-lining finish, the Velocette Thruxton was also produced with an unusual blue frame, forks and seat and silver petrol tank with gold lining. In 1968 the Lucas magneto was phased out, and Velocette replaced it with coil ignition.[11] A total of 1108 Thruxtons were built, but, although it had more power than the Venom, the Thruxton couldn't save Velocette, and the company was wound up in 1968, with remaining stock sold until mid-1970. The Thruxton has gone on to become one of the most sought-after Velocette motorcycles today, however, and many private owners convert standard Venom models to the more valuable Thruxton specification.[3]
24-hour world record
On 18 March 1961 a production Velocette Venom Clubman set the 24-hour world record at an average speed of 100.05 mph (161.01 km/h).[2][12] It was the first motorcycle of any size to top the 100 mph in 24 hours, and to this date no other machine of the same capacity has been able to equal or improve on this record.[4] The record attempt took place at the Montlhery speed bowl, a 2.7 km (1.7 miles) concrete track just outside Paris with a very uneven road surface and poor track lighting.[13] A team of six French riders were accompanied by Motor Cycling journalist Bruce Main-Smith, who achieved the best lap time of 107 mph despite the poor lighting conditions. After securing the 12-hour record at more than 104 mph (167 km/h), the team went on to complete the 24-hour endurance record attempt. Stopping only to change riders and refuel (from a bucket using a funnel), the Venom secured the world record. The publicity was very important for Velocette, as the success revived sales of the Venom, which went on to become one of Velocette's best-selling motorcycles.[10] The Venom which set the 24-hour world record is now on display at the British National Motorcycle Museum.[14]
Racing success
The 'Thruxton' version of the Velocette Venom ridden by Dave Dixon and Joe Dunphy won the Thruxton 500 endurance race. (In 1965 the race was actually held at another disused airfield, the Castle Combe Circuit). In 1967 two Velocette Venom Thruxton motorcycles, ridden by Neil Kelly and Keith Heckles gained first and second places in the Production TT that was first staged at the Isle of Man that year, with Kelly also recording the fastest lap at 91 mph.[3] Prepared by London Velocette dealer Reg Orpin, the winning motorcycle was far from standard, for as well as being in 'Thruxton' trim, the valve gear included titanium tips to the pushrods and valve caps. A Norton Manx piston had been specially engineered at Velocette's Hall Green Workshops, and it had cam followers on needle rollers as well as light alloy timing wheels. It was nearly all for nothing, however, as Kelly failed to start and the rest of the field left him struggling to kick start the Venom. Orpin managed to start it just in time, and, despite the poor start, Neil Kelly caught up with the other riders within three miles and went on to win the 500 cc class, recording 121 mph as he passed the Highlander speed trap.[10]
See also
References
- ↑ 1.0 1.1 Krens, Thomas; Guggenheim Museum Staff (1998). Thomas Krens; Matthew Drutt, eds. The Art of the Motorcycle. Harry N. Abrams , Incorporated. ISBN 0-8109-6912-2, 9780810969124 Check
|isbn=value (help). "Velocette Venom 499 cc • 1963 • United Kingdom • Bore x Stroke: 86 x 86 mm • Power output: 34 hp @ 6,200 rpm • Top speed: 105 mph (169 km/h) • Collection of Harry Lindsay" - ↑ 2.0 2.1 Mitchel, Doug (2001). Motorcycle Chronicle: One Hundred Years of Magnificent Machines. Publications International. pp. 126–127. ISBN 0-7853-3350-9, 9780785333500 Check
|isbn=value (help). "The single cylinder Venom was introduced in the late Fifties, and while it was a capable sporting machine, it was overshadowed by various British twins. It's 500-cc engine produced a very respectable 36 horsepower, enough to propel the Venom to near 100 mph. A Venom equipped with the 'Clubman' option could top the century mark." - ↑ 3.0 3.1 3.2 3.3 Kemp, Andrew; De Cet (2004). Classic British Bikes. Mirco. Bookmart Ltd. ISBN 1-86147-136-X.
- ↑ 4.0 4.1 Walker, Mick (19 December 2008). Velocette: The Racing Story. The Crowood Press Ltd. ISBN 978-1-84797-072-5.
- ↑ 5.0 5.1 5.2 5.3 5.4 5.5 5.6 5.7 Bacon, Roy (1988). British Motorcycles of the 60's. Osprey Publishing. ISBN 1-85648-166-2.
- ↑ 6.0 6.1 6.2 Melling, Frank. "Memorable MC Venom Thruxton". Retrieved 2009-05-31.
- ↑ 7.0 7.1 Currie, Bob (1980). Great British Motorcycles of the Fifties. Hamlyn Publishing Group Ltd. ISBN 0-86363-010-3.
- ↑ Gibbison, David. "Velocette Evolution". Retrieved 2009-05-30.
- ↑ "Velocette Viper Scrambler". Retrieved 2009-05-30.
- ↑ 10.0 10.1 10.2 Reynolds, Jim (1990). Best of British Bikes. Patrick Stephens Ltd. ISBN 1-85260-033-0.
- ↑ Clement Salvadori (November/December 2009). "1962 Velocette Venom Clubman". Motorcycle Classics. Retrieved 2009-10-08.
- ↑ De Cet, Miro (2001). The Complete Encyclopedia of Classic Motorcycles: informative text with over 750 color photographs. Rebo. p. 271. ISBN 90-366-1497-X, 9789036614979 Check
|isbn=value (help). "...in 1956 there were two super sports machines, the Venom 500 cc and the Viper 350 cc. This year saw the introduction of an uprated LE called the Valiant, which was phased out in 1963, but not before the Vogue version was introduced.
A great feat was achieved when a Venom set the 24 hour world record for a 500 cc motorcycle, reaching 100.05 mph at the Monthlery banked circuit south of Paris in France on 18–19 March 1961." - ↑ d'Orleans,, Paul. "24 hour record". Retrieved 2009-05-31.
- ↑ "The Velocette Owners Club". Retrieved 2009-06-06.