Not so for B-Spoke Design's Nathan Greene, of Riverside, and his father, industrial designer, Mike, and the 1970s road racing motorcycle they replicated.

Nathan said that their project began after reading an article in a UK historic motorcycle racing magazine.

Tuner and dealer John Blanchard in the late 1970s commissioned Britain's Harris company to design a one-off racer around one of its own frames to compete in club racing.

The Greenes were inspired.

They started to replicate the bike about two years ago, armed with a few published photos from the magazine, modeling foam, fibreglass, steel tubing, aluminium, time and patience.

A gleaming, canary yellow road racer was the result.

"Once we read about Blanchard's racer, our interest was aroused," Nathan said.

"This was at the time when two-stroke racers were starting to dominate on the track, yet Blanchard decided to base his racer on a four-cylinder, four-stroke motor.

"He enlisted frame builder Harris to design the frame and body parts — the frame design they came up with was ground-breaking at the time and became the norm in later years.

"At first, we saw the project simply as an interesting technical challenge, but the further it progressed, the more enthusiastic we became."

Blanchard called his creation the Flying Dragon and it went on to regularly beat the TZ350 Yamaha two-strokes at club races.

When the father and son team set about replicating the bike in Nathan's workshop, Mike first scaled a photograph of the original bike and set about drawing a 3-D version of the frame on his laptop.

Nathan, meanwhile, fashioned the petrol tank by hand from a solid block of modeling foam and made moulds for a fibreglass seat and fairing as well as machining other parts out of solid aluminium.

"We set up the front forks at the required angle on a heavy steel beam and added our self-made swinging arm to establish the required wheel base," he said.

"We then positioned the motor between the forks and swinging arm at the correct height and distance and started cutting, bending and spot-welding tubing to make a frame that joined the front and rear of the bike.

"The motor and wheels were then removed and all the welding completed."

Nathan said that the project then required what is called a "dry build".

"First we built and assembled the whole bike, unpainted, fitting the engine, forks, rear suspension, brakes, exhaust, wheels, tank, seat, mudguard and fairing, to make sure everything fitted," he said.

"Then we pulled it completely apart, painted everything and reassembled it, ready for the track."

Nathan said that the Flying Dragon was ahead of its time when built in the late 1970s.

"We looked at it as a bike that just had to be built and find it hard to believe that no one has tried to replicate it before us," he said.

"It's an iconic bike, easily the equivalent of the Suzuki XR69s or Honda CB750 racers of the period.

"We're very proud of it and taking it to the track and running it has been a real thrill — the wailing exhaust note certainly has more connection with the 1970s than today's decibel-restricted racers.

"Modern bikes all have a shrill, neat sound, but this has the sort of blare you just don't hear any more.

"When we ran it at the historic 2 plus 4 meeting at Baskerville in October, we had people standing around the pits just waiting for us to fire it up and smiling broadly when we did."

Mike said that he loved it when people, who didn't know the bike's history, saw it at the races and tried to work out what it was.

After two years of measuring, calculating, building and tuning the father and son answered as one when asked whether they'd consider building another.

"NO."