Road Bike Crank Length Advice

He had traded in his pain free old bike so was not aware of the crank lengths on that bike.

Road bike crank length advice. If power in martin s study was affected only 1 6 with a 25 mm change in crank length we can safely assume that it would change less than 1 when comparing the normal range of available crank lengths. If you are changing the cranks on an existing bike. Crank length is measured between the pedal hole and spindle hole center to center and perpendicular to the spindle. Alan d 5 7 170cm with short legs for height 74 8cm had recently bought a new bike and started to experience hip pain.

Some older british cranks like the one in the photo above are in inch sizes. It was just a number however. Crank length changes may help solve long simmering aches and pains but they re most effective when you re doing everything you should be doing to be strong on the bike. Even if you are in that range then the crank length that your bike came with may not be ideal for you particularly if you like to ride far.

Although using cranks 170mm and under is better spending time with a bike fitter to find your optimum length is key. Some bike fitters will have an adjustable crank so the pedal can be moved to simulate crank lengths from 155 185mm. Should i get a bike or a new crankset with 170 mm arms or 175 mm arms. At one point during the dominance of the english bike industry prior to world war ii an attempt was made to standardise crank length 6 5in 165mm but road racers started to challenge that.

Frame sizes crank lengths bike frames are typically offered in a range of sizes from about 50 cm to 63 cm for men and about 44 to 56 cm for women as shown in the example geometry chart from cannondale on the right. You can try this during a bike fitting. Many cranks carry markings identifying the length. Some riders agonize over crank length differences of 5 mm.

Get a bike fit and then buy a cheap crank or borrow a crank. I just thought that the longer crank on the mountain bike was because mountain bikers required extra leverage for slow. Almost all crank lengths are multiples of 5 mm making super accurate measurement unnecessary. A good bike fitter will help you find the best crank arm length for you.

Femur length in inches should be the same as crank length in cm alternately femur length in cm divided by 2 54 equals crank length yields the same result this is based around the idea that the upper leg is the major lever when applying force to the pedals and that the lower leg is the connecting rod and plays little part. For some riders though with ongoing knee hip or lower back issues crank length could be a factor.