The Scotsman will contest the time trial stage on his ``old faithful'' because he says can handle it better than his new $18,000 bike on the 250-metre wooden velodrome, which he describes as ``egg-shaped''.
``I need to be comfortable and not fighting for control on those bends,'' he said. ``It is even more important if it is windy.''
His wife Ann flew in on Tuesday with the special shoes he needs for the old bike which has carried him to world titles and records. The shoes have the pedals bolted on.
``Last year (at the world championships) I was only the third fastest qualifier but I eventually took the title,'' said Obree.
``I just hope to get faster as I get further into the (Olympic) competition.''
Last year, Obree was persuaded by his business manager Frank Quinn to buy a new bike with back-up spares built to his specifications.
It followed an embarrassing scene at the Nations track meeting in Paris when ``old faithful' broke down and there were no spares.
On Wednesday he cannot afford the slightest slip against opponents such as Andrea Collinelli of Italy, Australian Bradley McGee and German Heiko Szonn.
The multi-million dollar results system which has, by turn, infuriated and -- eventually -- amused journalists with its bizarre offerings, began the day in benign mood.
First thing on Tuesday it awarded a track cycling world record to Australian Bradley McGee and then, in a spirit of Olympic generosity, delivered the same accolade to Denmark's Jan Bo Petersen.
The track cycling begins on Wednesday.
But then it got its bytes and bits in a tangle, turned nasty and spluttered out a waspishly misleading fencing result.
Hungary beat Spain in the semifinals of the men's team epee event, it said. Wrong, both Hungary and Spain were eliminated in the quarter-finals about an hour earlier.
In fact, the quarter-final results were wrong too, but that's another story.
Obree, the world record holder who rode to fame in track cycling on a home-made bike made from washing machine parts, was 15 seconds off the pace in the final World Cup 4,000 metres individual pursuit last month, but Britain has stuck with him. ``The British Cycling Federation are hoping for a miracle, and knowing Graeme they could get one,'' said Boardman who contests the Olympic road events.
The qualifying rounds start on Wednesday.
Among Obree's serious challengers are Italian Andrea Collinelli who lost last year's world final to the Briton in Bogota, Colombia, and Australian Stuart O'Grady and Frenchman Philippe Ermenault.
Obree has always been full of surprises, producing world records and titles with his home-made bike since bursting on the world scene three years ago when he broke the world hour record of legendary Belgian Eddy Merckx.
He now has an $18,000 factory-made bike, but the Americans hope to win the battle for technical supremacy with their new narrow-profile bikes.
The first track gold, like the first road cycling gold, could go to France in the the one kilometre time trial, the only final of the day.
Florian Rousseau with two golds and a silver from the last three world kilometre time trial championships has to stop current world champion Shane Kelly of Australia.
Australia again will be the force to beat in the men's sprint which also opens on Wednesday with world champion Darryn Hill facing tough opponents in Canadian Curt Harnett and American Marty Nothstein.
France will be chasing more gold in the women's sprint where world champion Felicia Ballanger will be trying to end Erika Salumae's Olympic reign.
The Estonian has won gold at the past two Olympics.
1. Boogerd 100 km in 2.19.12 2. Blijlevens 0.20 3. Bouwmans 4. Henn (Dui)