By Fred Matheny
Q: I’ve been fitted by three different bike shops using different fit systems. Each shop measured me on and off my bike, which they all agreed is too small for me. They also came to the same conclusion regarding my body: extra-long legs and arms, very short torso. Even so, each system recommended different bike dimensions (top tube, seat tube, head tube, crankarm length, stem). I’m thinking about purchasing a super-cool new bike, but I want to make sure to get the right size this time. Is professional fitting a scam merely to make sure I’m unhappy with my old bike? — April S.
A: No, so-called pro fitting isn’t a scam, although different systems and technicians might come up with slightly different dimensions for your ideal bike.
A discrepancy may not matter, though. Here’s an example: A top tube that’s 1 cm shorter on Bike A could be compensated for on Bike B by a longer stem or a handlebar with a greater reach. To your position, the result is the same.
Also remember that there’s a fairly large “window” of proper fit.
Fitters need to know how the bike will be used. On a bike meant for racing or fast group rides, you may want to be more stretched out and have a greater difference between saddle height and handlebar height. For touring, lots of climbing or training on rough roads, you may want to be more upright. This is why slightly different fits aren’t necessarily wrong.
Another important factor is your flexibility. If a fitter doesn’t test it, then it’s doubtful the resulting recommendations will be on target.
Your own experience is important. Are you comfortable on your present bike? If not, think about what changes would make you happy. Perhaps it’s a higher handlebar or a stem with less reach. Then see which pro fit addresses these issues.
During more than 30 years in cycling journalism, Fred Matheny has written hundreds of fitness & training articles for top bike magazines and websites. Many of his best eBooks and eArticles are on sale in the RBR eBookstore. As a rider, he has raced to medals in state and national championships, plus a senior world record in the Team Race Across America. As a coach, he has worked with hundreds of riders at PAC Tour Training Camps, Carpenter/Phinney Bike Camps, and Dirt Camp.