The steam-bike (wonder why it never caught on): Antique motorcycle expected to break world record price at auction

Expected to reach £325,000 at sale in Las Vegas in January

Top speed of 117-year-old machine was 40mph

It is a bike whose inventor was once arrested for riding it but later released when police couldn't work out what crime he had committed.

And with a record like that it's not hard to see why it didn't catch on.

Now though this steam powered motorcycle is set to enter the record books, as the most expensive bike ever to be sold at auction.

The 117-year-old 'Roper Steam Powered Motorcycle' was designed by Sylvester Roper and is now expected to reach £325,000 when it is sold in Las Vegas in January.

Under the hammer: This steam powered motorcycle designed by Sylvester Roper is to be auctioned in the New Year and is expected to fetch £325,000

Enthusiasts from across the globe are expected to bid for the machine which had a top speed of 40mph and consisted of a boiler, steam engine stuck onto a hickory velocipede bicycle frame.

Roper connected the piston rods to cranks on the rear wheel axle and the solid wheels made for a very uncomfortable ride.

It also appeared that the machine was dangerous - as Roper actually died while riding it during 1896.

The bike worked by using a firebox and boiler suspended on springs from the frame between the wheels.

A charcoal fire heated the water to generate steam to power the engine. The exhaust steam was carried by tubing into a chimney behind the saddle.

Water was supplied from a reservoir that was part of the seat using a feed-water pump operated by the left-cylinder crank.

The rider could accelerate by turning the grip on the handles that acted as the throttle - in the same way as modern motorbikes.

Rudimentary: The piston rods connected to a crank on the rear wheel axle and the solid wheels made for a very uncomfortable ride

Following Roper's death the bike went through a number of owners who displayed it to the public until it was bought by its current owner in 1996.

Glenn Bator, head of Auctions America by RM's Vintage Motorcycle Division, said: 'Roper built two steam motorcycles and this one dates from 1894.

'Both of them exist and the other, earlier one that was based on a boneshaker cycle, is in the Smithsonian museum.

'At the time the internal combustion engine was in its infancy so no one knew that steam wasn't the way forward.

'When Roper invented his machine the word motorcycle hadn't even been conceived. It is amazing the machine has survived for this long.

Modern way: The rider of the 'Roper Steam Powered Motorcycle' could accelerate by turning the grip on the handles that acted as the throttle - in the same way as today

'Not only was it one of the very first motorcycles, but it was involved in the first ever motorcycle accident.

'Roper came off the bike and died and although it was shown he died from a heart attack it is not known whether he had it before or after he came off.

'The bike is still in working order and although the present owner hasn't sued steam, he has put pressure in it and the piston still works.

'It really was like riding with a locomotive between the legs just hoping it doesn't blow up.

'It is a significant piece of Americana and arguably one of the world's most important motorcycles.'