Bicycle Cranks, Crank That Gear Round!

We all need cranks to push our bikes, steel, alloy or carbon, you have to have them. For a road bike they were always double chain sets with two chain rings, now more and more bikes are being fitted with triples, to get up those harder hills or just to take things a little easier.

A double chain set would have chain rings of 52 or 53 teeth for fast riding and 39 to 42 teeth on the inside for easy riding or for the mountains. Triple chain sets usually have 50/40/30 teeth chain rings, or variations of those. Now there are also compact crank sets that you can have a 50 on the outside and 36 for the mountains.

Triple Crank

Mountain bikes mostly all have triple cranks, usually with a very small inner chain ring of maybe 26 or 28 teeth and then a 38 in the middle and a 46 or 48 on the outside, these lower gears are needed for the rough and mountainous terrain that is to be crossed.

Double Crank

Cranks also come in different lengths, for the steep indoor tracks you need 165 millimetre lengths, for the road and mountain bike the length you need is calculated on the length of your thigh, short thigh, short cranks etc.

For mountain bike you will use slightly longer cranks for more leverage and longer cranks cane be used for time trials and hill climbs on the road.

Bicycle cranks were first made in steel, then alloy and now carbon. Shimano and Campagnolo are the main manufacturers, but there are now many other carbon cranks by other companies, like FSA and Kuota.