The Union Cycliste International rejected five saddles that Obree offered. He said the only solution was to find a child's saddle that was small enough to suit his riding style and came within the rules as 'commercially available'.
A worker at the world championships then volunteered the mountain bikes of his sons Guiseppi and Fabio, who are nine and 10. The British team mechanic Sandy Gilchrist fitted one of the saddles to Obree's bike, which has carried him to world records and his world title.
Obree's anxiety lasted eight hours after the saddle he designed and made himself - which he describe as 'like a toadstool' - was rejected because it was a one-off and not commercially available. Four other saddles were banned because they were cut-down versions of conventional saddles.
Gilchrist returned triumphant from the UCI headquarters to say that the child's saddle had passed scrutiny. A relieved Obree presented the boys with an autographed racing jersey.
Obree's career has been full of success and some controversy. When he first arrived on the world scene and broke the one-hour record his bike brought smirks from some observers. Months later, he was the world champion in a record time, with the scalp of the Olympic champion Chris Boardman to his credit.
Then the UCI, anxious about technology overtaking the importance of the rider, decided to set standards for design in an attempt to eliminate Obree's riding style, which is like the position adopted by a downhill skier.
Obree developed the style because it suited his lanky body and also because an old shoulder injury prevents him using a conventional racing bike. Other riders have attempted his style but not with the same success. Obree said yesterday that he had heard that Miguel Indurain was adopting a similar posture in his attempt to break Obree's world hour record.
Obree said: 'Doubtless his saddle will have been designed and produced by a saddle company and will be allowed. But the one I designed and made is not.'
Boardman reported that although he still had a touch of his intestinal trouble, it was not affecting his racing. 'I think I may have twisted my bowel again, but there is not the excruciating pain there was previously,' he said. 'In fact, on a good day I believe the world record could go on this track.'
Obree and Boardman race today to qualify for the quarter-finals.