1961 Francis Beart 350 Manx Norton

Francis Beart is now gone. He died in 1983. But in his time he was one of the UK's top motorcycle tuners who built a reputation as the man to make your Manx Norton not simply go-with-the-flow, but get well ahead of it.

Trained at Brooklands, he also became involved in motorsport of the four-wheeled kind and worked with John Cooper 500 mid-engined racer.

Beart's bikes notched up eleven Manx GP wins, ten 2nds and three 3rds. He had a near-obsession with motorcycle weight reduction which was achieved by the usual methods of hollowing bolts, opting for lighter metals wherever expedient, and Swiss-cheese-drilling of components to within an nth of their lives.

He was also meticulous enough to daub matching colour paint on individual parts to ensure they were replaced exactly as he wanted them. And he kept a careful record of his changes and improvements.

This 350cc Manx Norton (above) was Beart's swan song. He built it for the late John Griffiths, founder of Stanford Hall Motorcycle Museum (in Lutterworth, Leicestershire), and Beart was perfectly aware that it was his final offering. That was why, it's said, he gave away his tools upon completion.

The bike has a colourful history including numerous modifications, a crash or two, various owners, and is offered with comprehensive technical information. The fuel and oil tanks are aluminium. The two-piece fairing is by Bill Jakeman.

The bike (nicknamed "Sabrina" after the 1960s movie starlet who was famous for ... something or other) was campaigned hard at the Manx GP, notably in the hands of Jimmy Guthrie, but despite its preparation by Francis Beart, this one was never a winner.

In 1982, motorcycle journalist and racer Alan Cathcart acquired the machine on behalf of the current seller, and it's been in the USA since.

Bonhams will be offering the bike for sale on Thursday 8th January 2015 at Bally's Hotel and Casino, Las Vegas, USA. The estimate is $50,000 - $70,000 (£32,000 - £45,000).

▲ That colour is Ludlow Green courtesy of the Ford Motor Company. We're thinking of slapping some on the Sump garage doors. But are we worthy of this illustrious hue? Probably not, we-thinks.

▲ Bill Jakeman was a top fairing manufacturer in the 1960s. He worked in both aluminium and fibreglass, and his creations commands a lot of respect today. We've heard that Jakeman was based in Blackpool, Lancashire. We've also heard he was based in Staffordshire and Kent (Edenbridge). If you know more about this man, please let us know. feedback@sumpmagazine.com

UPDATE: We've since been advised by an anonymous Sumpster that Jakeman fairings were made in a small village of Brindley Ford, in north Staffordshire (and we appreciate the tip).

▲ The 350cc OHC Manx Norton single. It knocks out around 35bhp, and is good for 115mph. Originally conceived by Walter Moore in 1926-1927, the bevel driven camshaft architecture was nothing if not a motorcycle revolution, pun intended. The engine was later reworked by Arthur Carroll, Edgar Franks and Joe Craig. Win or lose, this 350cc power unit was once a bloody nose for anything else in its class. Today, it's often overshadowed by the 500cc Manx. But when campaigned in historic classic racing, the three-fifty still lights up faces and is a serious piece of racing kit. Respect (etc).

▲ Check that recess in the petrol tank. Get your chin down there, forget the clock, tucked your elbows in and slipstream your way to victory. This 350cc Manx never won a GP. But it was "out there" in the hands of Jimmy Guthrie, and in our book it's still a winner.

— Big End