Originally Posted by pinnah
Mariner Fan,
Often, tightening the shifters a bit will be the cure.
How easily do the shifter levers move? If you can move the levers with a very light touch the tighten them a tad.
Nice bike. What size is the frame? Your sister must be tall.
Is it an optical illusion, the top tube seems to slope downward from the saddle to the head tube.
Bikes from this era can be extremely nice, my '84 Centurion still gets ridden regularly.