How to measure your Inseam, Torso & Arm
If you're having reservations about buying a bicycle over the Internet, you're not alone. One of the main reasons people hesitate to buy a bike online — instead of at their local bike shop — is that they can't actually sit on it or ride it first. After all, actually mounting a bike may be the best way to determine if it will fit you right.

Bike fit wins hands-down as the most important consideration when buying a bicycle, weighing in above such considerations as materials used, overall weight and brand. That's because a poor fit means discomfort, inefficient energy transfer and slower riding times — not to mention poor handling. Should you sacrifice a good fit for a good deal? Certainly not.

Before you shop for a bike, you'll need to take several measurements of your own body. Bicycle sizes are based on a person's height and body frame dimensions — not on their weight. No matter how much you weigh, you'll need a smaller frame size if you're a person of shorter stature with short legs and arms. and vice-versa.

Measure your inseam:

• This is best done barefoot.
• Stand against the wall
• Put a book between your legs so it pressed right up against your pelvic bone.
• Make a mark with a pencil on the wall along the top of the book.
• Measure the distance from the floor to the mark in centimetres.

Measure your Torso length:

• Place a book between your legs
• Measure from the top of the book to the beginning of the “V” in your neck i.e. the top of your breastbone.
• Hold the tape measure vertical when you take this measurement, don’t lie it flat against your chest.

Measure your Arm length:

• Make a fist
• Hold your arm out to your side so that your thumb faces the ceiling and your arm is parallel to the floor.
• Measure from the end of your collarbone to the middle of your fist.

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