| road bike | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Rider's Height | Inside Leg | Men's frame size suggested | Ladies' frame size suggested | Cranks length | |||||
| feet and inches | cm | inches | cm | cm | size | cm | size | mm | |
| 4'11" - 5'1" | 150 - 155 | 26" - 28" | 66 - 71 | 46 - 47 | XXS | 44 - 46 | XXS | 165 | |
| 5'1" - 5'3" | 155 - 160 | 27" - 29" | 69 - 74 | 48 - 49 | XS | 47 - 49 | XS | 167.5 | |
| 5'3" - 5'5" | 160 - 165 | 28" - 30" | 71 - 76 | 50 - 51 | XS/S | 50 - 52 | S | 170 | |
| 5'5" - 5'7" | 165 - 170 | 29" - 31" | 74 - 79 | 52 - 53 | S | 53 - 54 | M | 170 | |
| 5'7" - 5'9" | 170 - 175 | 30" - 32" | 76 - 81 | 54 - 55 | M | 55 - 56 | M/L | 172.5 | |
| 5'9" - 5'11" | 175 - 180 | 31" - 33" | 79 - 84 | 56 - 57 | M/L | 57 - 58 | L | 172.5 | |
| 5'11 - 6'1" | 180 - 185 | 32" - 34" | 81 - 86 | 58 - 59 | L | 58 - 59 | XL | 175 | |
| 6'1" - 6'3" | 185 - 190 | 33" - 35" | 84 - 89 | 60 - 61 | XL | 60 - 61 | XL | 177.5 | |
| 6'3" - 6'5" | 190 - 195 | 34" - 36" | 86 - 91 | 62 - 63 | XXL | 62 - 63 | XXL | 180 | |
The simple method used in the past was to stand over the top tube of the bike (with shoes off). Your crotch was supposed to be 3-5 cm (1-2 inches) above the tube for road bikes. Presently, this method is no longer considered accurate, mostly because of the wide range of bike frames used. An example of this is the difference between classic geometry with the horizontal top tube frame and frames with sloping geometry.
Crankset length is based mainly on the height of the rider and their riding style. Longer cranks are recommended if you are used to riding in harder gears (and at a lower cadence), as longer crankset gives you more leverage.
If you ride at a higher cadence, shorter crankset is recommended. The general recommendation for mountain bikes is to have a crankset from 2.5mm to 5mm longer than for road bikes. This means that if you have a road bike crankset length of 172.5 mm, you should have a mountain bike crankset length of about 175 mm.
| mtb and hybrid bike | ||||||||
|---|---|---|---|---|---|---|---|---|
| Rider's Height | Inside Leg | MTB - hardtail (full suspension frame recommended one inch smaller) | Hybrid bike | Cranks length | ||||
| feet and inches | cm | inches | cm | inches | size | inches | cm | mm |
| 4'11" - 5'3" | 150 - 160 | 26" - 29" | 66 - 74 | 13", 14" | XS | 13", 14" | 47 - 49 | 170 |
| 5'3" - 5'7" | 160 - 170 | 28" - 31" | 71 - 79 | 15", 16" | S | 15", 16" | 50 - 52 | 172.5 |
| 5'7'' - 5'11" | 170 - 180 | 30" - 33" | 76 - 84 | 17'', 18'' | M | 17'', 18'' | 53 - 54 | 175 |
| 5'11 - 6'1" | 180 - 185 | 32" - 34" | 81 - 86 | 19", 20'' | L | 19", 20'' | 55 - 57 | 177.5 |
| 6'1" - 6'3" | 185 - 190 | 33" - 35" | 84 - 89 | 21'', 22" | XL | 21'', 22" | 58 - 61 | 180 |
| 6'3" - 6'5" | 190 - 195 | 34" - 36" | 86 - 91 | 23'', 25" | XXL | 23'', 25" | 61 - 63 | 180 |
The simple method used in the past was to stand over the top tube of the bike (with socks on). Your crotch was supposed to be 7-10 cm above the tube for mountain bikes. Presently, this method is no longer considered accurate, mostly because of the wide range of bike frames used. An example of this is the difference between classic hardtail geometry with the horizontal top tube frame and bikes with full suspension.
Mainly based on the rider’s height and cycling style. When cycling in a harder gear (and at lower pace) longer crankset is recommended (to provide better leverage). High pace cycling is better with a shorter crankset. And for mountain bikes is generally recommended 2,5-5 mm crankset longer than in road bikes. This means that if your road bike crankset is 172.5 mm your mountain bike one can be 175 mm.
| kids | ||||||
|---|---|---|---|---|---|---|
| Age | Kid height | Inside Leg | Wheel Size (diameter) | |||
| feet and inches | cm | inches | cm | inches | cm | |
| 2-4 yrs | 2'10'' - 3'4'' | 85 - 100 | 12" | 30 | 12" | 30 |
| 3-5 yrs | 3'1'' - 3'7'' | 95 - 110 | 14" | 36 | 14" | 36 |
| 5-7 yrs | 3'7'' - 4'0'' | 110 - 120 | 16" | 41 | 16" | 41 |
| 7-9 yrs | 4'0'' - 4'5'' | 120 - 135 | 20" | 51 | 20" | 51 |
| 9-11 yrs | 4'5'' - 4'9'' | 135 - 145 | 24" | 61 | 24" | 61 |
| 11 and up | 4'9'' and up | 145 and up | 26" | 66 | 26" | 66 |
The simple method for chosing right size of the kids’ bike is size of wheels on the bike. As shown in the table above, simpliest is to buy a bike with the same wheel diameter as the inside leg length of your kid. But please pay attention to the ability of the bike to adjust saddle height in wider range. Another important consideration is a quality of the brakes on the kids’ bike. If the bike has a hand brake, let your kid give it a try if she/he can really handle it.
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