Some 25-32mm tires actual real size (Schwalbe, Continental, Vittoria, Michelin)
 

Hi all,

I am about to buy some slightly larger (~30mm) and cheap tires for my new bike (Kona *****Tonk).

I did a little research by ordering several tires of various sizes, putting them on the wheel, inflating and measuring their actual size, and I'd like to share the results here for the benefit of anyone who is interested.

The rim used was Mavic CXP33, standard rim with about 19.5mm outer witdh and 14mm inner width.
The size is expected to stretch a little with use, up to about 1mm, these measuremenst are of brand new tires (except Vittoria Rubinos that I measured used as well as new). The production batch chould also make a difference a mm more or less.

Continental Sport Contact
http://bikeforums.net/attachment.php...hmentid=502990
nominal size: 700x28
measured size (width x height): 26.8 x 26.2
weight: 420g

nominal size: 700x32
measured size: 29.6 x 28.6
weight: 465g

nominal size: 700x35
measured size: 33 x 33.8
weight: 510


Continental Ultra Sport
http://bikeforums.net/attachment.php...hmentid=502991
nominal size: 700x28
measured size: 27.2 x 25.7
weight: 400g


Vittoria Rubino
nominal size: 700x25
measured size: 23.5 x 21.5
weight: 335g

nominal size: 700x28
measured size: 25 x 24.2
measured size of used tires (stretched): 25.8 x 25
weight: 365g


Michelin Dynamic Sport
nominal size: 700x28
measured size: 26.3 x 25.8
weight: 370g


Schwalbe Spicer
nominal size: 700x30
measured size: 26.7 x 25.8
weight: 460g

No measurements taken here, but I have been running 35c Paselas on my gravel bike. New year's weekend it snowed here and I put on the Continental 37c ice tires. Great tires but much smaller than the Paselas on the same rims. (Open Sport)

Ben

Interesting data. Looks like everything measures "small" on your 14c rims, though as you note a couple might increase to nominal after some use.

I have 700x28 Rubino Pro III's that measured 26.8 to 27mm on a 16c rim.

Not a fan of Conti. They also run small.

First thing you need to know is that there are big differences in how companies size tires. Most will upsize, say a 32 is a 35 so the weight of the tire seems less.

So... you need to make some decisions. A tire can be basic, belted under the tread, or belted all way round. The bigger the belt, the harsher the ride.

Then there is the question of quality, mostly I look at Vittoria and Schwalbe for the quality.

Good midprice, midsize tires... Vittoria Randonneur, Rivendell Ruffy Tuffy and Roly Poly. The Rivendells are made by Panaracer and are basically Paselas, although I like them a little better than Paselas.

In terms of durability, the Paselas and Ruffy Tuffys trade off puncture resistance for a good ride, and are not high mileage tires. Vittorias and Schwalbes tend to offer durability at the cost of weight and a less supple ride. If I was going Schwalbe, I'd pick a Marathon Supreme or Racer. I've used the Racer. The last thing it is, is a racer. It's slow. But it is durable, the ride is decent, and it's not dog slow. A lot of durable tires are dog slow simply because they weigh so much.

There's a lot I don't know, what your roads are like, your expectations for a tire, but just as a guess, I'd suggest the Vittoria Rando. I have the Rando Pro on my bike. Vittoria sizing is accurate, which means their tires are big. Don't get the 32, I did and it wouldn't fit on my bike, it was just like what most companies sell as a 35. But the 28 should be fine.

here is a list showing actual widths etc of some 700x25 clinchers:

http://ddata.over-blog.com/xxxyyy/0/...her-specs.html


and here's the rest of the article .... (there's also a list showing tubulars)

Tire Rolling Resistance - Roues Artisanales - Bike tech magasine - handbuilt wheels boutique

Interesting chart, but where did you see that these are all nominally 25mm tires? Also, can't find indicated anywhere what width wheel these tires were on that they measured from.. which is kinda important. Actually IMO, "Actual width" as a standalone data point is somewhat meaningless except on perhaps a relative basis.

There is detailed reviews on this site: Road Bike Tires Rolling Resistance Reviews

I think GP4000S and GP4000S II may be exceptions. Most of what I've read about these says that they run wider than nominal on most rims.