Don't decide it by the S/M/L label: every brand measures it differently. What really tells you whether a bike fits you is the reach (and the stack). Compare the reach in the table with a bike you already know suits you, or with the range for your height and style. Between two sizes? Go short if you want agility, long if you want composure. The letter guides; the geometry decides.
It's the most-searched question and the worst-answered: nearly everyone replies with a height chart, exactly what matters least. Here's how to choose for real.
One brand's M can have the reach of another brand's L. If you choose by the letter, you're comparing things that aren't comparable. The good news: the number that does compare is in the geometry table of every bike.
The letter size isn't standardized: each brand decides what reach, what stack and what heights it assigns to each letter. That's why an "M" doesn't mean the same thing between two makers, and why choosing by the label —or by the height chart that comes with it— can leave you on a bike that's too short or too long without the letter warning you. The letter is catalog marketing; reach is physics.
If you already own (or have ridden) a bike that fits you beautifully, write down its reach and look for a similar one on the candidate: it's the most reliable way to get it right, because it starts from something you already know suits you. If you're starting from scratch, use the recommended reach range for your height and your discipline as a starting point, and adjust it with your style. The stack is the second figure: it decides how upright you'll sit, and it's best if it also fits, though it can be fine-tuned somewhat with spacers and handlebar.
It's normal, and here style and your proportions rule, not height alone. Go for the shorter size if you want an agile, playful bike that's easy to throw into slow corners and maneuver; go for the longer one if you prioritize stability, fast descending and composure at speed. If you have long arms and legs for your height (long reach proportions) lean to the long size; if they're short, to the short size. And remember that a reach that's too long can't be fixed with parts, whereas one that's slightly short can be stretched a little with the stem.
Compare the bike's reach with one that fits you well, or with the range for your height and style. The S/M/L letter only guides.
Short for agility and slow corners; long for composure and fast descending. Your reach proportions also tip the balance.
As a starting point. It ignores proportions and style, and each brand calculates it differently. Decide with reach.
Tell us your height, reach proportions, style and the bikes you're looking at, and we'll tell you what reach to target and which size to go for. Message us on WhatsApp
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