Having just received back my V5 for road registering my TXT 280 (thanks to all those who gave advice) I am now wondering what is an appropriate size of registration plate to get. The same size as my road bike would look daft, and yet some of the ones I saw at a trial today are no bigger than the width of the mud guard. I understand there is a legal requirement but wondered if there was an 'accepted' size for a trials bike?

Anything other than legal requirement is a risk you take.

Maybe, 'The legal one fell off constable, so I fitted this tiny one to get home', might work.

I have a full size plate that I attach to my back pack and a small size on the bike.

To fully comply with UK (and presumably EU) law not only does the plate & letters have to be of a certain size it has to be made by an approved supplier and their identification has to be on the plate.

 

Having said the above I don't know of anyone having been prosecuted for having an illegal plate and generally the police ignore a plate about 3/4 full size with clear letters. I know of a number who have had it painted on the newer narrow upward facing rear mudguards who have been warned to put it right or they will be done if seen again.

Despite being stopped a time or two I never had any trouble with the number plate painted on Bultaco and TY sized mudguards. On my newer bikes I have yellow polythene (from shell oil drums) hung from rear mudguard on a rubber flap. About 3/4 full size and no problems. Letters are by permanent marker.

Interesting points to take into account. Like most things if you don't abuse things then there is probably a general accepting if the effort if made. I suppose  trials is more likely to attract attention than a normal road bike with having no lights etc. Having said that some road sport bikes have tiny plates barely visible and they seem to be hardly ever pulled...famous last words.

That may depend on where you are in the country, a small number plate is almost guaranteed police interest at places of bike interest.

If you have 1 pre 2001reg or you can buy a personal plate with a prefix letter, single or 2 digits and 3 letters the smallest legal size is;  174mm wide x 163mm height.

Plate must be fitted to the most rear point of the vehicle.

Details for displaying plates are here;

https://www.gov.uk/government/uploads/system/uploads/attachment_data/file/359317/INF104_160914.pdf

Thanks. I did see some tapered ones but have elected to go for an 6x8 inch which seems a reasonable size. Now how to mount it without cutting lots of holes and easily removable at a trial.

Plumbed for a piece of 90 deg plate screwdd to plate and velcro to bike if atrong enough. As such easily removable.