Not in the Forest of Dean -
http://www.deanforestriders.co.uk/news.html
Extract from
Motorbikes in the Forest
There is a real danger to horse riders and drivers in the Forest from illegal motorbike riders. Motorbikes are forbiidden on Forestry Commission land and bridleways. However, this does not deter some individuals from causing mayhem in the countryside.
Please do report all instances of motorbike encounters. The police WILL be sympathetic to your complaints and they must give you an incident number when they log your call. The more incidents they receive, the more they will follow up. Even if the motorbike has no registration number, the police would want to know the colour of the motorbike, the colour of the rider's clothes and helmet and the area where the encounter took place. Planning of future joint operations between the Forestry Commission and the police will take reported 'hot spots', where incidents have been recorded into account in targetting stings.
The Forestry Commission is also interested in following up complaints of illegal motorbike usage.