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Myths in cycling: wider tires are slower

renehersecycles.com

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Re: Myths in cycling: wider tires are slower

#12
This is one of the reasons I love the emergence of the "Gravel" category of bikes. They look and have geometry similar to a road bike, but they have enough clearance for nice fat gravel tires.

I ride in Chicago (shitty roads, potholes & construction are everywhere), and love that I can put nice 38mm+ GravelKing Slick tires on the bike, and still have no problem keeping up with most road bikes. I've gotten funny looks from folks who're unfamiliar with the concept, but it's such a great setup.

Comfy/soft ride too.

Edit: Cannondale Topstone if anyone is curious.

Re: Myths in cycling: wider tires are slower

#13
I suffered with this myth for decades. Now, it didn't affect me too much because the narrower tires that I got, also took a lot higher pressure, and I usually inflated them to the max. And as a result of only caring about skinny tires, I neglected tire clearance on my frames.

Then a few years ago I got a bike that could take wider tires, and was good enough quality to really try out for real. Today I'm one more anecdotal data point in support of wider tires. Now, I don't necessarily opt for the lowest possible rolling resistance. Instead, lowering the pressure allows me to ride in greater comfort but without the tires feeling slow.

And of course other things affect rolling resistance too, such as (from what I've read) the suppleness of the sidewalls and other aspects of tire construction. And I'm not prepared to spend $$$$ to find the holy grail of tires.

Re: Myths in cycling: wider tires are slower

#14
post #5

Another one is that clip in pedals make you faster.

Do you have a source? Anecdotally I've found clipless to make my power transfer more efficient. Some quick googling shows this seems to be true:

"Mean power output was higher using clipless pedals ( = 617 watts, SD = 112) than toe-strap ( = 572 watts, SD = 77), and flat ( = 566 watts, SD = 83)." [1]

[1] https://scholars.fhsu.edu/cgi/viewcontent.cgi?article=1118&c...

Re: Myths in cycling: wider tires are slower

#15
post #2

If that were the case, surely Tour de France riders would use wider tyres to gain more grip going around corners, especially in time-trials or stages with sprint finishes. Doesn’t a greater surface area touching the floor means more frictional effects when pushing against the road?

From TFA: “ We tested our tires on smooth pavement at 29.5 km/h (18.3 mph), and found no speed difference between narrow and wide tires.”

A professional peloton rides at 28-30mph on the flat and significantly faster towards the end of a flat stage - I bet at higher speeds, for professionals where every percent matters, it does make a difference.

Certainly for my level (and I have ridden for an hour at 18mph average) it doesn’t.

Re: Myths in cycling: wider tires are slower

#17
post #2

If that were the case, surely Tour de France riders would use wider tyres to gain more grip going around corners, especially in time-trials or stages with sprint finishes. Doesn’t a greater surface area touching the floor means more frictional effects when pushing against the road?

The problem is that wide tyres tend to eat lots of momentum in corners.

When going mainly straight and/or on uneven ground, use wide tyres. When cornering a lot, use narrow tyres.

Re: Myths in cycling: wider tires are slower

#18
post #5

Another one is that clip in pedals make you faster.

I mean, they do, in the sense that they give a stronger and more secure connection to the pedals which lets riders commit more power.

This is relative to casual toe clips or flats. Compared to old school clips + tightly fastened straps with dedicated shoes they aren’t a huge difference performance wise but no one rides those any more because they’re much more dangerous and much less convenient.

Re: Myths in cycling: wider tires are slower

#19
post #7

I’ve ridden 25mm to 32mm tyres on the same bike, in the same season, and my (absolutely amateur, I’m 250lb and did 125 miles at 16mph) experience is that 32mm tyres are no slower, but are significantly more comfortable, and allow me to ride significantly longer with less fatigue. Does anyone else have any other data points?

I've spent a lot of time with 28mm tires, but I'm absolutely in love with my 38mm GravelKing slicks. I don't really notice much speed difference (if any), and the comfort level makes up for it if there is. I ride for fitness, so I'm happy.

More details in my other comment (I actually ride a gravel bike so I have the extra clearance for big fat tires if I need).

Re: Myths in cycling: wider tires are slower

#20
post #12

This is one of the reasons I love the emergence of the "Gravel" category of bikes. They look and have geometry similar to a road bike, but they have enough clearance for nice fat gravel tires. I ride in Chicago (shitty roads, potholes & construction are everywhere), and love that I can put nice 38mm+ GravelKing Slick tires on the bike, and still have no problem keeping up with most road bikes. I've gotten funny looks…

My bike is the best for the city.. got a Specialized Tri-Cross with 32mm tires.. can do everything and handle our horrible roads.
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