Pedalling Cadence + Gear Chosen = Speed
A typical pedalling cadence for a competent older rider is around 75 r/min (the middle column below). We'll excuse ourselves for dropping to 50 r/min on steep hills. Downhill racers might be tempted to whizz the pedals around at 125 r/min for a few seconds (that's all they'll manage!) to lift the top speed to something truly scary.
When considering gears, remember: in the big hills, you'll need the low gears for 30 minutes at a stretch; you'll never genuinely need the high gears.

Metres Development 
km/h @ pedal cadence of… 


50 r/min 
75 r/min 
100 r/min 
granny gear 
2 metres 
6 
9 
12 
very low 
3 metres 
9 
13.5 
18 
low 
4 metres 
12 
18 
24 
mid 
5 metres 
15 
22.5 
30 
mid 
6 metres 
18 
27 
36 
high 
7 metres 
21 
31.5 
42 
very high 
8 metres 
24 
36 
48 
top gear 
9 metres 
27 
40.5 
54 
An aside about the midrange gears: 18km/h appears in each column. If this is the speed you are comfortable cycling at, you should maintain that speed by 'spinning' the pedals at 75 r/min, not straining along at 50 r/min. Avoid pedalling too slowly (aim for 85 r/min but be satisfied with 75).
Perhaps, this is the time to suggest that you equip your bike with a computer that displays cadence (pedalling speed). Watch the cadence readout and keep it high by changing down a gear or two.
