Bicycle Fit – What You Need to Know
This section of our site is dedicated to articles that can help you understand bicycle fit better and to help you sort through the options so that you can select the best possible fitter and system.Selecting a bicycle fit is different from selecting many products in that it is in no way a commodity. When it comes to selecting a bike that fits and works properly for you, who you work with is often far more important than what you actually buy. Skill levels and qualifications vary immensely between fitters and the industry offers little in the form of test based certification. Like selecting a doctor, attorney or contractor, interview your fitter carefully before committing.
Common Fitting Systems and Techniques
Measurement Based Formulaic Fittings
These systems rely on body measurements that are plugged into a formula. The formula then calculates a recommended riding position or frame size.
Pros: Simple. Cheap. Requires little equipment or knowledge on the fitters part.
These systems are often similar to measurement based systems, but use a laser scan of the body to take measurements instead of manual tools. Like the measurement based systems, the measurements are placed into a formula which results in a bike size and set-up recommendation.
Pros: “Wow!” technology factor. Simple. Not fitter dependent (very little training of the fitter required).
These systems usually include elements of measurement based systems, but also include additional physical assessments and consider the rider on the bike. The goal is to make the fitting as similar to actual cycling as possible. A Size Cycle or other adjustable dynamic tool will often be involved.
Pros: When used properly, accurate and realistic. Comprehensive. Individual specific.
Motion Analysis/Capture Fitting
These systems are broken down into 2D and 3D categories and are usually advanced versions of a dynamic fitting. The motion analysis/capture system allows the fitter to capture and analyze the rider at specific moments during riding and thus gain greater insight into the details of the motion. The goal is to enhance the accuracy of the dynamic fitting session.
Pros: When used properly, can be the most accurate and realistic fit currently available. Very detail oriented and individual specific. Exceptional documentation potential.
|Recommendations: Whether manual or computerized, formula based fittings are inconsistent and limited at best as they fail to actually assess the individual rider’s needs comprehensively and thus skip key variables (like you actually riding…). For these reasons, we do not recommend any formula based systems. For example, those that depend on body measurements or body angles on the bike as their sole means of positioning. Dynamic fitting is the most reliable method currently available and, with the right fitter, a dynamic motion analyis fitting will be the most comprehensive fitting you can get.Regardless of the methodology used, it is up to the fitter to actually use the tools and methodology available to its potential. All the fit technology in the world can’t buy a good fit. Scrutinize your prospective fitter, their protocols and their credentials to make sure you know what you are getting. The more comprehensive the fitting, the more knowledgeable the fitter, and the better the communication between the fitter and the rider, the better and more reliable the end result.
Find more information on what steps and knowledge to look for in a dynamic fitting.
Associated Tech Articles on Bicycle Fit:
Aero Position Specific:
Cleat and Leg Alignment:
Frame Geometry and Fit: