Velocette MAC: the 350 that went to war and came back a tourer

The Velocette MAC was a reliable 349 cc overhead-valve single that coped well with the low-grade fuel of post-war Britain and became a popular commuter and touring motorcycle. Introduced in 1933 and built until 1959, it also served in military form during the Second World War.

Velocette MAC at a glance

Based on one source: the English Wikipedia article on the MAC.

History of the Velocette MAC

From the MOV

The first MAC was launched in 1933, developed from the overhead-valve Velocette MOV 250, which had suffered from reliability problems. The single-cylinder engine was enlarged to 349 cc and could comfortably reach 75 mph (121 km/h). The early MAC weighed 280 lb (130 kg) and had girder front forks.

The military MAC (WD)

In October 1939 the British War Office bought a MAC for testing at the Army Mechanisation Experimental Establishment at Cove in Hampshire, with French Army representatives also present. The tests were successful and the machine was modified to military specification in 1940. Velocette’s first order came from the French government, but the contract for 1,200 motorcycles was cancelled after the French capitulation and only one was delivered before the German advance. The British War Department took over the order in June 1940 and the machine became the MAC (WD), often called the MDD after its serial prefix. It had an upgraded clutch, cast-iron brake fittings in place of the pressed-steel drum, a shield over the crankcase, a carrying rack instead of the pillion seat and a blackout-masked headlamp. Production facilities were limited and the order was cancelled in September 1942.

The MAF and the missing WDs

The Velocette MAF had its foot gear change reversed to match other military motorcycles. An order for 2,000 was placed in June 1941, but only 947 had been delivered when it was cancelled in September 1942. A myth holds that a large consignment of MAC (WD)s was lost in the English Channel; in fact an order for 200 placed in July 1940 was never fulfilled, probably because the factory lacked capacity, and machines returned to civilian use often had their MDD numbers ground off, which reinforced the story.

Post-war development

MAC production restarted after the war. In 1948 the girder forks were replaced by air-sprung Dowty Oleomatic forks, and in 1951 by Velocette’s own telescopic forks developed for the LE, with coil springs and damping. The engine gained an alloy barrel and head with wider fins for cooling. For 1953 the MAC received fully adjustable rear suspension, a swinging arm and a tube frame, with an improved clutch and gearbox and a Burgess silencer in place of the fishtail. From 1954 it was sold as a sidecar machine, but production was halted by 1960: Velocette had spent £50,000 developing the Viceroy scooter, and despite continued single sales the company became insolvent.

Design and features

• Overhead-valve single: a 349 cc engine enlarged from the MOV 250 and good for about 75 mph.
• Military specification: the MAC (WD) with crankcase shield, carrying rack and blackout lamp.
• Modern forks: air-sprung Dowty Oleomatic forks in 1948, Velocette telescopics in 1951.
• Swinging-arm frame: fully adjustable rear suspension and a tube frame from 1953.
• Sidecar work: sold as a sidecar machine from 1954.

Velocette MAC versions

• Early MAC (1933–1939): girder forks, 280 lb, developed from the MOV.
• MAC (WD) / MDD (1940–1942): military version with cast-iron brake fittings and a carrying rack.
• MAF (1941–1942): military model with reversed foot gear change, 947 delivered.
• Post-war MAC: Dowty forks in 1948, telescopic forks and alloy top end in 1951.
• 1953 MAC: swinging arm, tube frame and fully adjustable rear suspension.

The MAC was the 350 cc stablemate of the MSS and shared its engine family with the Venom. More machines are in the Velocette collection.

Sources

• Velocette MAC, English Wikipedia: development, military models, post-war changes