The two trophies would be mini bike frames on kickstands, have disc wheels that turned and a plate to say what they were for, Mr Anderson said.
They would be about 300mm high by 500mm long, he said.
He said 9-year-old Miles and 12-year-old Dylan were doing 90 per cent of the work.
"Their enthusiasm to build it has been a lift for them.
"They are very, very excited."
Brazing, a unique and traditional form of welding which has been around for hundreds of years, was being used to make the trophies, Mr Anderson said.
Dylan said he was doing all the welding for the first trophy, as well as bead blasting and polishing.
He said he was happy it would be presented to the winners "because it's my work". The process had taken about five days so far.
His favourite part was "probably the welding, because it's one of the simplest".
Making the trophies had been an opportunity for his sons to experience starting and finishing a goal, and to show them the value of their work was appreciated, Mr Anderson said.
The two categories are Best Bike Shop and Best Other.
Other parts of the premises are able to be decorated if a window is not possible.
A gallery of all entries will be created and uploaded to the Rotorua Bike Festival Facebook page.
The winners will be notified towards the end of the festival and chosen by the Rotorua Bike Festival Charitable Trust.
For more information contact Priscilla Kirk on 021 941 800.
-To enter, take a picture and send to media@rotoruabikefestival.com by February 18.