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Questions and answers about sports

How can I measure what is a relaxed geometry frame?

5 min read

Asked by: Kristi Marks

What is relaxed bike geometry?

Aggressive geometry puts your upper body down lower for aerodynamics and the bikes tend to favor a more twitchy handling traits. Relaxed geometry has you sitting in a more upright position and the bike is setup to feel more stable at speed.

How do you measure a bike frame in geometry?

The Length is measured from the centre of the bottom bracket to where the top tube meets the seat tube. The angle of the seat tube in relation to the ground is then the seat tube angle. The angle doesn’t change much between different types of bikes, mainly staying between 71 and 74 degrees.
Jan 23, 2020

How are downtube bikes measured?


Quote from video: And it's simply measuring from where the fork or the headset cut meets the bottom the frame where the headset cut into the top of the frame.

Is seat tube length the same as frame size?

Bikes are measured mainly by the bike frame size, which is the length of the seat tube.

Does higher stack shorten reach?

In general, a higher stack will be paired with a shorter reach on a more comfort-focused endurance bike, while a lower stack and longer reach will make for a more racy ride position. As mentioned above, these are very useful measurements to determine how well a bike will fit you and the sort of riding it’s good for.
Jan 14, 2021

Does bike geometry affect speed?

The short answer is that ‘it depends‘. Some viewers commented that maybe it just doesn’t matter. It absolutely does matter and indeed the geometry of the bike is the most powerful way that we can change the riders experience of the bike.
Jan 23, 2019

Is a 67 degree head angle slack?

The head tube angle is the angle of the head tube in relation to the ground. A “slack” angle is anywhere from 63 to 66 degrees. This means the fork of the bike is going to stick out farther, creating a more stable ride at high speeds, but also be slower handling.
Jul 6, 2022

What does bike geometry mean?

Bike geometry is responsible for how a bike looks, rides, and handles, and having a basic grasp of the key figures will go a long to way aiding you in comparing different bikes and what is best for you.

How do I know if a bike is too big for me?

If you struggle to make turns or need to sit up straight to reach the handlebars, the frame is likely too large. You may also notice that you cannot quickly turn or pick up speed easily due to the way that you sit in a larger frame. Pain or discomfort after riding also indicates that the frame is too big for your size.
Jun 26, 2021

How are downtube sizes measured?

Measuring Seat Tube Length



To measure the seat tube length, measure from the center of the bottom bracket along the center of the seat tube, to the top. Some manufactures stop at the very top above the seat post clamp while others stop below. This measurement is typically taken in centimeters for road bikes.
Mar 24, 2018

What size is a 17.5 inch bike frame?

Sizing conversion

Alpha size XS M
Frame size 13.5 17.5
Rider height 147-155 cm 4’9”-5’1” 161-172 cm 5’3.4”-5’7.7”


What size bike should a 5’9 Man ride?

Road bike sizing chart

Rider Height (feet/inches) Rider Inseam (inches Bike Frame Size (centimeters)
5’4″-5’7″ 28.5″-30″ 52-54 cm
5’6″-5’9″ 29.5″-31″ 54-56 cm
5’8″-5’11” 30.5″-32″ 56-58 cm
5’10”-6’1″ 31.5″-33″ 58-60 cm

What is a good stack to reach ratio?

As a rule of thumb, road bikes with a high ratio of stack to reach (1.5 and greater) are best for less flexible athletes or those with longer legs and shorter torsos; road bikes with a lower ratio of stack to reach (1.5 and lower) are best for more flexible athletes or those with longer torsos and shorter legs.
Jun 4, 2018

What is more important stack or reach?

For a given reach, a greater stack puts you into a more upright riding position; your hands will be moved upwards and your body position will rise more towards the vertical.
Apr 21, 2020

How do you choose a reach and a stack?

Quote from video: People also ask

What is aggressive bike geometry?

Aggressive geometry puts your upper body down lower for aerodynamics and the bikes tend to favor a more twitchy handling traits. Relaxed geometry has you sitting in a more upright position and the bike is setup to feel more stable at speed.

What does slack geometry mean?

A “slack” geometry means that these angles are lower, which in effect moves the rider further back in relation to the center of the bike and the front wheel is further out in front. At the extreme end of this design concept is the downhill bike.
Apr 23, 2012

How does bike geometry affect ride?

The higher the bottom-bracket height, the higher the centre of mass of the rider, and so the more the bike tends to pitch when faced with bumps, hard braking or steep gradients. In this sense, a lower bottom bracket improves stability in much the same way as a longer wheelbase.
Sep 11, 2020

What does bike geometry mean?

Bike geometry is responsible for how a bike looks, rides, and handles, and having a basic grasp of the key figures will go a long to way aiding you in comparing different bikes and what is best for you.

Is a 68 degree head angle slack?

The head tube angle is the angle of the head tube in relation to the ground. A “slack” angle is anywhere from 63 to 66 degrees. This means the fork of the bike is going to stick out farther, creating a more stable ride at high speeds, but also be slower handling.
Jul 6, 2022

How do I choose a bike frame?

The best way to check the frame size of the bike is to simply stand over the frame. Make sure both of your feet are on the ground. Ideally, you should have an inch between your crotch and the bike’s frame if it is a hybrid, racing, or touring bike.