4

I know little about all of this, so, go easy on me. I've got a mountain bike, fairly light in weight and rarely ever used for anything other than road use. The current tires say 58-559 / 26x2.35. Is it possible to go for thinner tires with the same Rim and how much will this affect the ride?

  • Welcome to Bicycles @Will. I edited your question a little. It's not that we are all 'merican, just for consistency. – andy256 Jul 15 '15 at 1:08
  • 3
    One needs to be very careful when changing tire widths with 26" tires. With 27" tires and 700C tires the rim diameter remains the same when you change tire width, but this is not always the case with 26". You must check any replacement tires to assure that the ISO size is XX-599. See Sheldon for more info. – Daniel R Hicks Jul 15 '15 at 2:08
5

What you want for road use is slick tires -- tread and knobs are bad for road use. You have 26" (ISO 559) rims, so you need 26 x (something) tires where (something) is a number in decimal form (e.g. 1.75).

Going for smaller tires will lower the bike a bit, and smaller tires have to be run at higher pressure (so you'll get less cushioning). There will also be changes in rolling resistance (You may want to read the whole "Tech Info" column on the right side of the Schwalbe page).

As for how small you can go, technically you can mount pretty much any 26x(something in decimal) tire on, but the rim width should ideally be of the right width so the tire doesn't roll off or increase the risk of flats or rim damage.

I'd probably look at something with a puncture protection belt, like the Schwalbe Marathon Plus (26 x 2.00 will likely be one of the larger slicks they sell, and you can likely go narrower depending on the rim width).

  • 1
    Something like a Schwalbe Big Apple might also fill the bill. They come in 50-559 and 55-559. – dlu Jul 14 '15 at 15:48
  • Big apple would work too - lower pressure, higher volume, more supple rubber for a softer ride. – Batman Jul 14 '15 at 16:14
  • Technically you cannot "mount pretty much any 26" tire". You cannot mound a 26x1-3/4 tire in place of a 26x1-3/8 one, for instance. The rim diameter will be different by 19mm. – Daniel R Hicks Jul 15 '15 at 2:11
  • 1
    Neither of those will mount on a ISO 559 rim to begin with. I've updated the answer to be more clear about this. – Batman Jul 15 '15 at 12:28
  • Smaller tires don't have to run at higher pressure. And "cusioning" is a function of both tire pressure and tread width, so a narrower tire with a higher pressure can be a "wash" in that regard. – Daniel R Hicks Jul 15 '15 at 12:52
3

It is possible. For typical mountain rims, the low limit is somewhere around 28mm. Some differences from mounting narrower tires are following:

  • Less cushioning from tires: Smaller tires can not absorb as much shock from from curbs, cracks in the pavement, etc. On the other hand, smaller tires can be made with more flexible casing and absorb small vibrations better.

  • Quicker steering: With wide tires friction resists steering more than with narrower ones. Depending on the geometry, the bike will be either more agile or feel nervous. Smaller rotational inertia from lighter tires will add to the feeling.

  • Rolling resistance: It is true that for similar tires with similar pressure the wider one has lower rolling resistance. However, narrower tires can be made more flexible and use higher air pressure so the difference is not that great. For example, compare the numbers for 4 bars with narrow tires and 2.5 bars for wide ones: https://www.fietsersbond.nl/sites/default/files/test_schwalbe.pdf

  • Reduced height: The entire bike will be a centimeter or two lower

  • Looks: Large empty spaces in forks can look strange to some people.

0

I regularly switch between my 26 X 1.5" road tires and my 26 X 2.5 inch mountain tires with no issue, they both fit on the rim just fine.

  • Hi, welcome to bicycles! This is more of a comment than an answer, since it's just an anecdote (it may not apply to the rims of the bike in question) and it doesn't address how it affects the ride. – DavidW Aug 26 at 17:47

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

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