
The V-twin Silver Arrow wasn't a great success although it pioneered several of the features which Bert Collier adopted for the Hawk. The Arrow was sophisticated but not particularly fast; comfortable and quiet, but not quick. It was adored by the press (it gave them plenty to write about!) but sold slowly, so something with a greater turn of speed was called for. The V4 Silver Hawk delivered the goods with a four-cylinder, 592cc, 26bhp engine capable of propelling the motorcycle to 85mph. Importantly, the Hawk also had a chassis and suspension to match its engine's potential.
In their own words, the Colliers described the Silver Hawk as; 'the most fascinating machine to ride that has ever been built. It combines the silence, smoothness and comfort of the most expensive motor car with a Super-Sports performance. On top gear alone, the machine will run from as low as 6mph to over 80mph, while the acceleration given by the four-cylinder overhead camshaft engine in conjunction with the four-speed gearbox must be experienced to be believed. This is the only four-cylinder machine in the world equipped with a Spring Frame.'
The new Matchless motor was essentially two narrow-angle V-twins mounted side by side on a one-piece cast block, with a single-piece cylinder head housing a bevel-driven overhead camshaft. Both V-twins had crankshafts which were set across the frame and thus avoided a 90-degree turn in the transmission (although an alternative layout might have turned the engines through a right angle and used a shaft drive to the rear wheel. That suggestion might be 80 years too late to be of any help…)
The four valves in the top end were completely enclosed and well lubricated, and could be easily accessed by hand to be adjusted. Fuel was delivered to the combustion chamber by a single, centrally mounted Amal carb. The compact engine used roller bearing big ends and a chunky, built-up, two-throw crankshaft that featured substantial cheeks which doubled as flywheels. Positively lubricated phosphor bronze bushes were at either end of the crankshaft with a central roller bearing. The oil tank lived at the front of the engine, by the frame downtube, and bolted directly to the crankcase, thus removing the need for unsightly external oil lines. It is indeed a very tidy design, as you can see from the photos.
Four gear ratios were normally selected by hand; the primary drive chain lived in an oil bath and final drive was also by chain. Drive for the Lucas dynamo/coil ignition system was provided by skew gears from the vertical camshaft tower on the right of the engine, which itself is decorated with the most glorious model badge to ever grace a motorcycle. (I'm not biased. No. Not in the slightest).
With dimensions of 51mm by 73mm, the Hawk retained the relaxed, long-stroke feel of many vintage engines, helped by its mild compression ratio of 6.1:1. Although the Hawk's engine suffered somewhat from overheating (less than did the Square Four of the period), it was extremely easy to start and could be turned over by hand. Once on the move it would pull smoothly from below 10mph in top gear, although the model's much-vaunted smooth sophistication lessened as it neared its top velocity. Matchless claimed that the Hawk engine was 'vibrationless and silent in operation and capable of very high output', Cyril Ayton reckoned that 'the Hawk seemed to become more frenzied with increasing speed'. By contrast Ariel's Square Four gained a reputation for more effortless acceleration - but we should remember that it wasn't until a whole half century later that Honda finally cracked the basics of a competent V4 motorcycle engine.
However, the V4 engine wasn't the only remarkable thing about the Silver Hawk. It used a similar chassis to the Arrow, with an extremely advanced form of rear suspension. The cantilever triangulated system featured two springs set horizontally underneath the separately spring saddle, with two mechanical friction dampers on either side of the springs. This really did live up to its potential and worked well with the girder forks (which could be adjusted by the rider while on the move) at the front, providing a supremely comfortable ride for the time.
The Colliers also included an adjustable linked braking system on the Hawk. 'The brakes are well engineered' said Titch Allen, who found that the eight-inch drums worked extremely well with the rear suspension, although he wasn't a great fan of the linked system. 'I cannot get used to the forks chattering under braking when I have only used the footbrake.
Another innovation was the sprung centrestand - rarely seen at the time, when front or rear wheel stands were the norm. Matchless also offered the option of a positive stop, foot controlled gearchange, for purchasers willing to spend an additional 30 bob. The 370lb Silver Hawk was the top of the range machine and in De Luxe trim came with full electric lighting and horn, a proper ignition switch and indicator light, speedo and oil indicator. If you wanted the detachable luggage carrier it would cost you an extra fifteen shillings, however!
Apart from some issues with overheating when run at high speeds for sustained periods, the first version of the Hawk also had a habit of guzzling oil (a modification for 1932 helped with that problem). Setting up the bevel gears correctly was tricky for home mechanics, so it was common for them to whine or rattle in a manner which would feel very familiar to owners of much later bevel-drive Ducati twins.

The Silver Hawk cost £72 new in 1933; £5 more than Ariel's Square, and the price of the Matchless rose to nearly £79 in the four years of its production run. Just 550 Silver Hawks were sold between 1931 and 1935. These days the Silver Hawk sells for between £30,000 and £45,000 depending on its condition. A complete and unrestored example, in 'barn find' condition, sold for £28,000 in 2009. A recently restored Hawk fetched £35,000 at auction in October 2010; that bike looked very handsome indeed but was effectively a museum piece.
In 1931 Torrens of The Motor Cycle reported that 'at 50mph the engine of the machine was unnoticeable and barely a sound from engine or exhaust could be heard. The spring frame was excellent and the only guide to its presence was the exceptional comfort of the machine.' The handling was 'just about perfect; there was no tail wag, chopping or pitching, even when roughish bends were taken nearly flat out.' He believed that 'no finer machine had ever left the Matchless works, and that on all-round performance it had very, very few rivals.'
Mick Walker reckons that the Silver Hawk was 'in many ways a brilliant design which was unfortunate enough to be conceived at just the wrong moment in history… The majority of customers for whom the Silver Hawk had been designed were simply unable to make a purchase of such a luxury item in those times of economic gloom… It was a notable design worthy of a better fate.
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