Last Updated: April 28, 2026 To measure a bike wheel size, look at the sidewall of your tire — it’ll show two numbers like “700×28c” or “29×2.25”. The first number is the wheel diameter (700c, 26”, 27.5”/650b, 29”). The second is the tire width. If the sidewall’s worn off, measure the rim’s bead-seat diameter (BSD): … Continue reading How To Measure Bike Wheel Size: A Complete Guide