According to a latest revisions affected in the Central Motor Vehicles Rules of 2021 vide 23rd amendment the changes notified are to come into force with effect from April 1, 2022.

As per provisions of these amendments, hereafter registration renewal of a 15 year old car will now cost Rs 5,000, compared to the existing fee of Rs 600 almost nine times the cost for a new registration. For motorbikes that are more than 15 years old, the renewal charge is fixed at Rs 1,000, compared to the existing Rs 300, more than 3 times.

Additionally, the fitness renewal certificate for a light motor vehicle will be Rs 7,500 and for old medium goods or passenger motor vehicles Rs 10,000. The notification further says an additional fee of Rs 50 for each day of delay after the expiry of certificate of fitness shall also be levied.

Source: https://www.thequint.com/my-report/union-budget-motor-vehicle-act-senior-citizens-expect-extension-in-vehicle-registration-validity