The 19-year-old Canberra man, who was caught riding under the influence earlier this year, has been fined and has been banned from driving for six months.

The teenager was riding drunk at 3am, wearing all black, and without a helmet.

Police arrested him and charged him with two traffic offences, holding him overnight in the lock-up.

Most Canberrans might not realise it, but riding a bike drunk is a criminal offence, which is treated in the same manner as drink-driving.

It is also an offence to ride animals, which the legislation identifies as "horse, cattle or sheep", while intoxicated.

The territory's drink driving laws, somewhat archaically, even extend to those commandeering "animal-drawn vehicles".

The teenager, who represented himself in the ACT Magistrates Court on Friday, said he had no idea that riding while drunk was a crime.

He said he was "sincerely sorry" for what he had done, and said spending a night in police lock-up had been a real "eye-opener".

The 19-year-old asked the court not to convict him of the offence.

But Magistrate Bernadette Boss rejected his request for a non-conviction order, saying his lack of a clean driving record made it impossible.

She said whether he chose to break his own skull was a matter for him.

But Dr Boss said the consequences would affect others, including the public, who would have to pay for his medical bills, and his family and friends, who would have to deal with the trauma of what could only have been a "very serious injury", should he have crashed.

She said he presented a danger to the public by riding the bike while drunk, and said he had been very fortunate not to have been hit by a car.

Dr Boss said that if a driver ran him down, he or she would have to deal with it for the rest of their life.

The teenager was convicted of the crime and fined $400.

He was disqualified from holding a driver's licence for six months, reduced from three years because of his personal circumstances, future prospects, and young age.