A BALLARAT teenager who pleaded guilty to 20 driving related offences will spend five-and-a-half-weeks in a Youth Training Centre before he is sentenced on all his charges.

Magistrate Kay Robertson yesterday sentenced James William Bartlett,18, to three months in custody on two counts of driving in a manner dangerous, but said she would wait until next month to deal with the remaining charges.

The Ballarat Magistrates Court heard Bartlett had driven at speeds of up to 115kmh in a 60kmh zone and led police on a high speed car chase before fleeing on foot on August 11 this year.

He had also driven repeatedly while his licence was suspended and while his car was in an unsafe condition.

"In my view there are still a lot of unanswered questions," Ms Robertson said yesterday.

"The driving I have heard about today is of grave concern to me."

Ms Robertson said Bartlett had consistently lied when confronted by police, which suggested something else was going on.

She requested a report from juvenile justice and a psychologist to be prepared for when Bartlett reappears in court for sentencing on the remaining charges on September 30.

Bartlett has pleaded guilty to a range of charges including seven counts of unlicenced driving and two counts of driving while disqualified.

Bartlett's defence lawyer Anjali Griffiths urged the court to take into account Bartlett's young age and his early plea of guilty.

Bartlett spent nine days in custody at the Ballarat police station after concerns were raised about him spending time in adult custody in Melbourne.

Bartlett is also expected to face other driving charges still to come before the court.