HE'S no Olympian, but at 59 John Bennett reckons he's exceptionally fit for his age.

"My resting pulse is 48 beats a minute. If I ride 26km from my home (in Kinglake West) into town I burn 1000 kilojoules," John says. And the best calorie burner of all, he says, is taking part in the annual National Penny Farthing Championships in Tasmania, which are on this Saturday.

The championships attract competitors from around the world, and John competes in the 200m sprint, track race of about 1.5km, 32km road race, relay and the over-50, as well as heats.

"If you put a top bike rider on a penny-farthing, for the first 2km I'll beat them," he says. "But after they get a feel for it, they'll leave me for dead. On a penny-farthing you use as much of the top part of the body as your legs. It's very physical."

The bike may well be a great exercise machine, but for John, the greatest joy is actually building a penny-farthing. He has built seven bikes for himself - including two for his daughter, Kathleen, who also competes in Tasmania. And he also takes commissions, with a penny-farthing taking two weeks to make at a price of $3500.

His love of constructing, though, started long before the penny-farthings. John's life calling has been vintage and veteran motorcycles, manufacturing parts in his home workshop with a specialty in fuel tanks, which he beats and fabricates from raw steel.

It was this manufacturing knowledge that equipped him to make a penny-farthing.

"I first rode one at the age of 10 but I fell off it. Because I've always been interested in old things and bikes, a penny-farthing was always on my must-build list," says John, who wears modern-day lycra rather than top hat and tails when astride a bike.

John gathered pictures and researched the construction and in 2007 started building one.

The result was not ideal.

"It was a beautiful road touring bike but I couldn't race it. The handle bars were too high, the pedal length was too long, the seat was perched in the wrong position."

So he pulled it apart and set about reinventing the model, which included lowering the handlebars - he now uses a loop style to avoid injury if he should fall. John makes all components on the bike, except for the wheels, which he sources from Queensland - "you wouldn't bother making them yourself, each spoke is handmade".

When Black Saturday ripped through Kinglake, John managed to save his own home, but his mate's place where he stores a lot of his bikes from the '20s and '30s - Acmes, Warratahs, Elliotts and other exotics - was razed. "It was a collection built up over a lifetime, worth more than $100,000, but uninsured. That's the risk I took."

Just two weeks after Black Saturday John decided to take part in his first National Penny Farthing Championships.

"I reckon it helped enormously, just to get away from here and go for a ride," he says.

"Ever since then it's become a real community for me."