You need to get spinning on a real bike again!
Do lots of things in small gears, consider sessions like...
Seated accelerations from start and rolling.
Seated sprints down hills.
Accelerations off another riders wheel.
Riding the track in an easy gear.
Borrow a BMX off your kid brother.
A session where you go fast slow fast slow (but remaining in the same easy gear)
A session where you maintain a constant high pace but swithch between your big and little ring.
Flying 200's on the track (easy gear).
Riding behind a derny (motorbike) in a low gear.
As a track sprinter you should always be looking to accelerate your legs, so consider anything with accelerations and explosiveness (from standing and very importnatly from high speed). You will need to start the training with an 'easier than racing gear' and then gradualy move up the gears. So that you don't lose strength, do similar training in a 'bigger than racing gear'. As the season draws closer bring both of the gears closer together so that on your first day of racing you hit 'race gear'.