The recent prosecution of a former Isle of Man sportsman of the year for riding illegally through Manx woodland should deter others, a minister said.
Professional enduro rider Jamie McCanney, 25, last week pleaded guilty to unlawfully riding his motorcycle in Kings Forest, Greeba on 15 June.
He was given a six-month conditional discharge and ordered to pay £50 costs.
Environment Minister Geoffrey Boot said the case showed it was a “serious offence” to break forestry byelaws.
The Isle of Man Centre Auto Cycle Union (ACU) has also banned McCanney from taking part in local competitions for six months.
A ranger for the Department of Environment, Food and Agriculture spotted a group of motorcyclists, including McCanney, riding in the woodland.
Byelaws ban the use of motorcycles off-road on government land “without permission”.
Mr Boot said that while “responsible use” of the land was “encouraged”, the byelaws were designed to “prevent property damage and disturbance to wildlife”.
The prosecution was a reminder to people that it was “an offence to ride motorcycles in woodlands or on open hill land without permission”, he added.
The competition ban issued by the sport’s local governing body recognised the “seriousness of the offence”, he added.
A spokesman for the Isle of Man Centre ACU said it “deplores any action taken by an ACU member or non-member whose actions contravene the goodwill, built up over many years, of the landowners who generously allow us access to their land”.
“Action, such as the recent suspension given to Mr McCanney, will be taken in all cases of illegal riding on private land including that of the Isle of Man Government,” he added.