I have been looking for some tires I could buy but I couldn't find exact numbers (My current tires are 27.5 x 2.8)

I found one which was 27.5 x 2.10 or should I get one which is 27.5 x 2.1 Both of them are the same price but I don't know which one to get, can you please tell me?

  • 3
    Normally 2.10 is the same as 2.1, but with bike tires I would not bet on it.
    – mattnz
    Commented Nov 2, 2017 at 3:31
  • @user35375, what's the rim width inside? Commented Nov 2, 2017 at 5:17
  • 1
    You can get away with anything 2.8" wide or less. You might get away with going up a little, if there is clearance between tyre and frame.
    – Criggie
    Commented Nov 2, 2017 at 8:46
  • 2
    If you change tyre size substantially, you may need new tubes as well. I went from 2.1" down to 1.5" and the old tubes were very hard to get in resulting in folds and pinches.
    – Criggie
    Commented Nov 2, 2017 at 8:47
  • 1
    2.1 and 2.10 will be the same. It’s when you start dealing with fractions that you get in trouble.
    – Batman
    Commented Nov 2, 2017 at 10:22

3 Answers 3


2.8 is bigger than 2.10.

When you run a bigger tire, you have to worry about the tire rubbing on the frame or fork.

Running smaller tires are usually simpler.

Tire sizes have to be appropriate for the rim width; wide tire on narrow rim could have some control issues/sloppiness (and if you had rim brakes, that could also cause some rubbing). Narrow tire on wide rim could increase risk of damage from hazards. See this page for details: http://www.sheldonbrown.com/tire-sizing.html

  • The width chart at the bottom of that page doesn't go big enough for this case but a similar ratio should be OK on many rims given that rims tend to be sized atthe narrow end for the stock tyres to save weight.
    – Chris H
    Commented Nov 2, 2017 at 9:06

You have three basic concerns when thinking about changing tire width

  1. Will different tires fit your rims?
  2. If fitting wider tires, will they clear the frame and fork (and leave enough clearance for mud or debris if riding off road)
  3. How will different width tires affect the ride and handling of the bike.

There are various resources for determining tire width / rim inner width compatibility, including the chart on the Sheldon Brown page linked to in other answers here. Tire manufacturers should provide min and max rim widths for each tire model and size.

Whether you can, or want to drop to a 2.1" from a 2.8" tire in terms of ride and handling depends on what type of bike you have and what riding you are doing. Presumably at 2.8" you have an MTB so you need to think about the potential for reduced bump absorption and traction with narrower tires.


2.8 is a fairly wide tire. Mountain bike I assume. Moving to a 2.1 tire is a big difference. Here are some more questions to consider:

  • What terrain do you ride on? (streets, trails, singletrack?)
  • Bead type (wire or folding?)
  • Tubeless tires (yes or no)?
  • Is there something you dislike about your current tires?

If riding on trails/singletrack, I would stick with the wider tire, as you can use lower pressures for more grip without fear of pinch flat.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.