Track gearing is calculated in the old 27" way, so 48/16 x 27, i.e. 81". If a coach says 84" he/she's talking about 48x15. You can still use Sheldon's calculator, but just pick the 27" nominal wheel size for track purposes.
Yes, you need to work on spinning your legs faster. It won't happen overnight, as it's predominantly a neuromuscular adaptation. 48/16 @ 25mph is 107rpm. To be able to respond to constant changes in pace, you should be able to turn at least 130rpm on the flat (48/16 = 30.5mph), and top 40mph downhill in your current gear (if you were inclined to try).
Riding a big gear on the road all year is the biggest barrier to developing souplesse. Like mikec said, spinning away on something in the 60-65" will work wonders, and is common practice in the winter for many racing cyclists.
Lowering your saddle 5mm may help. Having to overextend is like a cadence brake.
Track gearing is calculated in the old 27" way, so 48/16 x 27, i.e. 81". If a coach says 84" he/she's talking about 48x15. You can still use Sheldon's calculator, but just pick the 27" nominal wheel size for track purposes.
Yes, you need to work on spinning your legs faster. It won't happen overnight, as it's predominantly a neuromuscular adaptation. 48/16 @ 25mph is 107rpm. To be able to respond to constant changes in pace, you should be able to turn at least 130rpm on the flat (48/16 = 30.5mph), and top 40mph downhill in your current gear (if you were inclined to try).
Riding a big gear on the road all year is the biggest barrier to developing souplesse. Like mikec said, spinning away on something in the 60-65" will work wonders, and is common practice in the winter for many racing cyclists.
Lowering your saddle 5mm may help. Having to overextend is like a cadence brake.