# 第4B部分：滚动阻力和阻抗

## 滚动阻力（CRR）和套管损失

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该图是Al Morrison和Tom Anhalt的一个例子，该钢鼓在钢鼓上测试了非常有效的轮胎。  请注意，随着气压的增加，滚动电阻会降低，这是轮胎在接触贴片下偏转较少的结果。  这种类型的数据已经存在了很多年，部分原因是“更高的压力更快”神话，我们都相信这很长时间了。

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## 考试

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铣削的路面表面：我们的测试课程有900米！

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CRR与三种不同表面粗糙度的轮胎压力。  原始的Tom Anhalt，Al Morrison数据以蓝色表示。

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## 轮胎压力课

Silca团队现在计划扩大测试，以查看更多的压力，更多的骑手重量，更多的轮胎宽度和替代表面。  您可以想象这可能会导致我们进入的数据集的大小，但是结果令人着迷且令人兴奋！  一个学到的教训是，4天大的路面虽然“光滑”的外观比您想象的要高，但仍然“柔软”，这似乎既增加了总滚动损失，又增加了阻抗线。  最近在相同的道路表面完成的测试，如今已有近2年的历史显示了CRR明显下降，并且断裂点后曲线的陡度下降。

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4天大与2岁沥青在同一课程中

### 得到教训

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• 轮胎压力不是最大化或最小化变量，但可以针对您的体重，轮胎尺寸和课程条件进行优化
• 最好将压力设置为断裂压力以下的几个PSI，而不是在断点压力上方的几个PSI
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• 粗糙和/或软表面具有更陡峭的阻抗线，使总滚动电阻更高，最佳轮胎压力较低
• 更多的柔软轮胎将具有不太陡峭的CRR和阻抗曲线，并且更宽容轮胎压力误差

### 8 评论

• Clin Lashway

Anyone know why the graph of the TT bike on smooth pavement (green line) has a break point around 112 PSI, but running similar parameters into the Silca calculator comes up with 94 PSI? That’s a huge difference of 18 PSI.

• Travis Verhoff

@Mike believe it or not almost none of the world tour teams are on tubulars for most races in 2023. Tubeless has really taken over the peloton in the last couple of years.

• Mike

There are more reasons for to choosing a type of tire than saving a wee bit of rolling resistance. I think that’s the reason why the pros continue to use tubulars.

• Gus

Hi Gmorly

It simply isn’t true what you are spewing that you would puncture at 80psi. Sure if you weigh 110kg that might be the case and then again I highly doubt it, but not for anyone of a healthy weight. I even tried going back to tubed clinchers from tubeless and I have not experienced this puncture tendency despite the older guys from the club being oh so terrified of the potholes.

Using italians as an argument has got to be the worst argument ever as they are notoriously rigid and traditional with their equipment. You might as well get your team tactics from Movistar if that’s the logic you’re pushing.

Rolling resistance is in fact very important going up hill, because you can’t compensate as much aerodynamically with the body or with a nice tyre profile/tread pattern like conti tyres have. The whole “I’ll just get stronger legs” argument is complete bogus. If you want to get stronger legs, train well and maybe just push harder on the pedals. All you are robbing yourself of is comfort, grip and speed. In reality you are the only pseudo scientist among us, but that’s okay… some people thrive best on their own delusions. Out here in the real world, the pros ride 80-100psi on 25mm tyres(many train on 28mm) and as low as safely possible for Paris Roubaix. If they use tubulars or clinchers with latex tubes, they will actually calculate what pressure to start at to still have decent rolling resistance for the normal asphalt and then have dropped enough pressure to go well as the cobble sectors start.

• The Pinnacle

Tubulars are falling out of fashion because roller test data shows that they have more rolling resistance for a given pressure compared to clinchers or tubeless. My understanding is that the reason for this is that the glue is adding additional compliance which is then converted into waste heat.
This explanation seems square with anecdotal experience with tubulars feeling smoother. So if there is additional compliance from the glue, or maybe some other mechanism making the tubular feel ‘smoother’, then wouldn’t it stand to reason that the impedance break point of a tubular would occur at a higher pressure?
In other words, are tubulars really slower when compared to clinchers or tubeless at each tire’s optimal pressure? Part of me suspects that the watt differences at optimal pressures are less than what an equal pressure comparison would indicate.
Has this been tested by anyone?