A FOREIGN motorcyclist snapped travelling at 139mph on a 60mph road in Moray escaped without a fine because the speed camera could not detect the bike's number plate details.

The incident was the worst speeding offence recorded in ­Scotland between April 2013 and June this year, and could have resulted in a dangerous driving charge.

The motorcyclist was caught by a speed camera on the A96 Keith to Huntly road, a single carriageway cutting through a remote part of north-east Scotland popular for motor­cycle tourism.

However, police were unable to trace the offender as the image of the number plate was too blurry. They could only be sure that the motorcycle was registered abroad.

The breach is among the 20 worst speeding offences revealed by road safety charity the ­Institute of Advanced Motorists (IAM), following a freedom of information request.

All but one of the speeding offences in Scotland occurred on A-roads, in contrast to England where the four worst speeding incidents over the last year occurred on motorways.

Neil Greig, the Scotland-based director of policy for the IAM, said this was probably because Scotland has fewer motorways, and speed cameras north of the Border tended to be located on A-roads.

Seven drivers were caught on the A74, including one travelling at 121mph - 51mph over the limit - on the southbound carriageway of the Glasgow-to-Carlisle road north of Moffat, in Dumfries and Galloway.

The notorious A9, known as Scotland's deadliest road, accounted for four of the worst offenders, including one motorist who travelled at 127mph in a 70mph stretch of the Perth-­Inverness road near Moulinearn, in Kinross-shire. The only motorway offence to make the top 20 was recorded on the M80 near Dunipace, in Falkirk, where the driver was caught doing 119mph.

Mr Greig said the gravity of the breaches meant the drivers involved should have been charged with dangerous driving, which carries a minimum 12-month ­driving ban.

He said: "That sort of speed is just ridiculous. The person who's doing it has no chance if anything goes wrong with their vehicle, because the road is not designed for that speed. Also, the people around them don't expect anyone to be travelling at 139mph, so they're putting other road users at risk too. It never ceases to amaze me when I see these figures. It's a dangerous driving offence rather than a speeding offence when it gets to this level.

"When you're more than 20 to 30mph above the speed limit you're not talking about someone who has 'drifted' over the limit - you don't drift up to 139mph without knowing what you're doing."

Dangerous driving convictions can also carry prison sentences of up to two years, an unlimited fine and a maximum 11 penalty points.

James McLoughlin, spokesman for road safety charity Brake, said: "These are appalling examples of dangerous driving. Breaking the speed limit by any amount is selfish and risky, but drivers who flout the law by exceeding the limit by such significant amounts are putting themselves and other road users at almost certain risk of death or very serious injury.

"We're calling on the police to crackdown on such irresponsible behaviour and for the courts to impose more severe penalties on drivers who risk killing themselves and others."

A Police Scotland spokesman said the force supported the comments made by the IAM, and would "rigorously enforce the law on speeding which remains a major factor in many road accidents across the country".

He added: "Our message is clear - if you are caught speeding, you are breaking the law and will be given penalty points plus a fine."