Skip to main content
Bicycles

You are not logged in. Your edit will be placed in a queue until it is peer reviewed.

We welcome edits that make the post easier to understand and more valuable for readers. Because community members review edits, please try to make the post substantially better than how you found it, for example, by fixing grammar or adding additional resources and hyperlinks.

6
  • 7
    And if you use solid steel wheel on railroad tracks you will loose almost zero. Those tests are made assuming aperfectly smooth surface, perhaps a pine velodrome. Real roads are not like that.
    – Vladimir F Героям слава
    Commented Sep 1, 2020 at 13:14
  • 1
    @VladimirF Bicyclerollingresistance is quite aware of that. However, we still have the pure rolling resistance as underlying losses. Juhist already tried to compare wide tyres. Taking suspension loses, in the way Jan Heyne defines them, into account the much less supple gravel tyre will have even more losses.
    – gschenk
    Commented Sep 1, 2020 at 13:35
  • 1
    @gschenk I do not beleieve that your final implication is so simple. Jan Heine quotes this: "As tire width increases, tire pressure decreases. So a wider tire performs better in terms of rolling performance." and says "It is understood that to offer good performance, the wider tires must be supple, otherwise, you lose too much energy to flexing the tire casing at it deforms with each wheel revolution." Of course, a gravel tyre will be slower. GCN calculated that a gravel bike will be slower even at Paris-Roubaix. But I do not believe it is so simple, more supple is not more losses.
    – Vladimir F Героям слава
    Commented Sep 1, 2020 at 14:37
  • 2
    @VladimirF indeed. If the calculation were simple we wouldn't fiercely debated tyre width for a decade. It's good to have measurements for rolling resistance on a flat smooth surface (the drum has some embossed parts afaik). This part of friction always plays a roll on compact surfaces. The measurements also allow to compare compounds. They are not the whole picture, which is too complex and variegated to answer, but still it makes a substantial part: Have pressure and width equal, the tyre with faster compound and supple casing will be faster.
    – gschenk
    Commented Sep 1, 2020 at 14:48
  • 1
    @VladimirF technically the surface used for the tests is a rough diamond pattern plate that is intended to simulate asphalt surface. The comment about suppleness refers to the fact that wide tires used to come with thick treads and low density casings, two things that did not make them supple. This is not any more the case for all tires.
    – ojs
    Commented Sep 2, 2020 at 8:11