Canterbury police say they are concerned at the rising number of disqualifed drivers who are putting petrol motors on mountain bikes and using them on the road.
Acting Senior Sergeant Scott Richardson says that in recent months they have dealt with riders who have been drunk and disqualifed, with some involved in accidents, using the modified bikes.
Mr Richardson says people have the impression that the modified bikes are power-assisted pedal cycles, which require a motor of 300 watts or less - but they can easily exceed 50 km/h -- and often have motors producing five to ten times more power than allowed.
For the bikes to be legal on the road, he says, they must be registered as a moped, and display plates; riders must also wear a motorcycle helmet.
