Hi. I'm Will from the Outspokin Bicycle and Sport Shop located in Newbury, New Hampshire. Today we're going to learn how to measure a mountain bike frame. Measuring a mountain bike frame is rather important. It has a lot to do with stand over, clearance and upper body extension. But basically when you look at any measurement for a mountain bike frame the measurement you're seeing has a lot to do with the space between the center of your bottom bracket or crank arm up to the top of the frame. So in essence it's either an inch or a centimeter measurement. It comes from this center of this bolt right here. And then follow the seat tube all the way to the top and the center or the top of what we call the top tube is going to be where we end the measurement. So it might be a 17 1/2. Also equates to a 44 1/2 centimeter. But there's your measurement right here. That's how you measure a mountain bike frame.