Top Tube (TT)Updated 2 months ago

Top Tube length (TT) is typically measured in inches. It is the distance between the centre of the Head Tube and the centre of the Seat Tube. See Image below.

Freestyle BMX Top Tube:

The table below provides valuable insights into freestyle BMX top tube lengths for frames and complete bikes, correlating rider height with wheel size and appropriate top tube measurements. Top tube length is a crucial factor in BMX bike geometry, significantly impacting the rider's performance and comfort.

For freestyle BMX, top tube lengths typically range from 20 to 21.5+ inches for serious riders. Shorter riders (around 157-168 cm) often prefer top tubes around 20.25 - 20.75 inches, while taller riders (175 cm and above) may opt for lengths up to and exceeding 21.25 inches. The choice between a shorter or longer top tube affects the bike's handling characteristics and the rider's positioning.

Riding a shorter top tube results in a more responsive and agile bike, ideal for technical tricks- most modern day street and park riders will be running a shorter top tube. It allows for quicker spin rotations and easier manoeuvrability. However, it can feel less stable at high speeds and may be less comfortable for taller riders.

Conversely, a longer top tube provides increased stability, especially at higher speeds, in the air and for landings. It offers more room for the rider to move around on the bike and can be more comfortable. The trade-off is slightly reduced manoeuvrability and potentially slower spin rotations. Longer top tubes are favoured by taller riders, trail riders and riders who just enjoy a more relaxed feeling bike.

A 21-inch top tube length serves as an excellent median point, offering a balance between responsiveness and stability. This length is versatile enough to accommodate various riding styles and rider heights, making it a popular choice for those seeking the best of both worlds in freestyle BMX.

Below is a general guideline for someone delving into Top Tubes. It's a good starting point to go off.

Race BMX Bikes Top Tube:

Below is the size guide for race bikes. This includes the Bike Size, Rider Height and appropriate Top Tube Lengths for anyone buying an aftermarket race frame or complete race bike.