Sam Harrison pictured racing on the bright pink Planet X bike that was one of those stolen.
Six bikes belonging to a 16-year-old cycling champion, who represents Wales and Great Britain, have been stolen from the garage of his family home.
The bikes used by Sam Harrison and others belonging to his father and brother, five, were taken from the garage in Risca, Newport, on Friday.
They are worth about £12,000 and Gwent Police are investigating.
Sam said he was worried he would not be able to perform to his best at next week's European Championship selection.
He is borrowing a bike from a friend to continue training and said he will probably have to use it when he takes part in a training camp where cyclists will be selected to take part in the championship in Belarus.
"It was a big shock and it's really affected my training," said Sam of the theft.
"I've borrowed a bike from my mate but it's not the same as having my own bike. I'd spent ages customising my bikes and getting them in the right position to fit me.
"I'm worried I'm not going to be able to perform my best on a borrowed bike."
His father, businessman Simon Harrison, 42, said his son - a Cross Keys college pupil - said he was "devastated and angry" for Sam.
"It is a disaster really for Sam. His bikes are so specialised," he said.
"He practises on average three hours a day, six days a week. I am very, very angry and was absolutely devastated for my five-year-old son Oliver and my older one because he's going to be severely hampered at something he loves and is really good at."
Mr Harrison said the bikes, which were chained and locked up inside their detached garage, were stolen at about 0430 BST on Friday.
He was woken by his neighbour on the small cul-de-sac where he lives early on Friday, who told him he had heard a noise and saw two men wearing black balaclavas driving off in a Land Rover.
The bikes stolen include a bright pink road bike worth £2,500 given to him by Planet X, the team Sam rides for.
"Only Planet X team members can ride these bike so I'm hoping someone might recognise it - it's a very bright pink," said Mr Harrison.
Other bikes taken included a Pinarello bike worth £2,500 and two mountain bikes, worth a combined £3,000.
"He needs at least three bikes - two for competition and another to train on," added Mr Harrison.
"He also does velodrome cycling but luckily his bikes for those were at the velodrome."
He said Sam, who has represented Wales for the last two years and GB since the end of last year, is working towards a place in the 2012 Olympics.
He was chosen for a place on a boys' Olympic development programme a year early.
In the velodrome, he is British champion in the under-16 points race and scratch race and holds the British record for the under-16 2km pursuit.
The cyclist was also in the top 10 shortlist for the BBC Young Sports Personality of the Year in 2008.
If anyone has any information about the stolen bikes they can contact Gwent Police on 01633 838111.