Perhaps a little history might help. We all know of Leyland's
most successful DD model, the Olympian. Such was its popularity, it
was the only Leyland bus model which was allowed to continue
production after the Volvo takeover. In 1993, Volvo decided to drop
the Leyland name altogether and improve upon the Olympian chassis
by using Volvo parts and engines, which resulted in the Volvo
Olympian. Later, with the introduction of stepless DDs from rival
companies, Volvo decided to introduce their own stepless DD too.
The Olympian chassis was modified by moving the radiator position
from the front to the farside, behind the front axle, so that a
stepless entrance is possible. The new chassis' model number is
B10TL and its model name is Super Olympian.
The B9TL was a further improvement on the B10TL. For some reasons,
the side radiator position didn't go down too well. So, it was
decided to relocate the radiator to the rear. An improved engine
was developed which is smaller but produces more power. Hence, a
new chassis, the B9TL was born. Oddly, the name Olympian was given
to the new chassis. Why? I don't know.
