Admittedly, the interplay of all geometry data is far too complex to be able to predict the riding behaviour of a bike based on an isolated geometry value. The overall concept is decisive for the riding characteristics. Nevertheless, it makes sense to familiarise yourself with the secrets of E-MTB geometry to read in. This is because many variables are simply character-building, and they can be an important indicator for the right Size and the Field of application be.
When designing an e-mountainbike, developers must already have the area of use and target group in mind: A comfortable touring bike requires different geometry characteristics than an aggressive enduro bike. One factor must not be forgotten. The rider. Because the anatomical characteristics of the bikerarm, leg and upper body length as well as weight distribution and riding position, influence how a geometry actually feels.
If you study the relationship between body anatomy and bicycle geometry, you can learn which geometry characteristics are best suited to your personal circumstances. In issue EMTB 1/21 we will show you how to decipher the complex equation - and thus achieve your Dream bike find. Here is a brief explanation of the most important terms.
1 Reach / Stack
These two parameters effectively provide information about the size of a frame. They describe the distance between the bottom bracket and the upper edge of the head tube and therefore the position of the rider when standing. These values therefore have a decisive influence on the wheel load distribution in the downhill position. The reach stands for the length, the stack for the height of the frame.
2 Seat tube length
For decades, the length of the seat tube was the decisive factor when choosing a frame size. This is now a thing of the past. With modern, long-stroke dropper posts, the right seat height can be selected relatively independently of the seat tube length. Before buying, check whether you can set your desired seat height with the telescopic seat post fully extended.
3 Seat angle
The seat angle describes the position of an imaginary line between the bottom bracket and saddle in relation to the horizontal and thus determines where the rider sits on the bike in relation to the bottom bracket. The flatter the angle (smaller values), the further back the saddle moves. This makes the riding position more elongated and the weight distribution more rear-heavy.
4 Chainstay length
The distance between the bottom bracket and the rear wheel axle is called the chainstay length. No other factor is discussed more on E-MTBs. The reason: This value drastically differentiates many e-MTBs from classic bikes. The original e-MTBs had extremely long stays because the first generations of motors were large and bulky and shorter rear triangles were not possible. As a result, the first e-MTBs quickly lost their reputation: unwieldy, sluggish and not much fun. In the meantime, the motors have become more compact and chainstay lengths can be realised like on normal mountain bikes.
5 Steering angle
To put it simply, the steering angle describes how flat the bars of the fork lean forwards in the bike. With a flat steering angle (small values), the front wheel moves further forwards and the wheelbase increases.
6 Wheelbase
The wheelbase indicates the length of the bike from front to rear axle. It influences the smoothness and manoeuvrability of an E-MTB.
In issue EMTB 1/21 we checked the character of two quite different e-MTBs - and explain which frame geometry is the right one for which area of use. EMTB 1/21 - The magazine for e-mountain bikers is in stores from 16 February. You can obtain the new EMTB conveniently in the Subscription, in our Online shop and as an app edition for Apple and Android.
