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Bicycle Rolling Resistance: Tire Rolling Resistance Tests and More

bicyclerollingresistance.com

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Re: Bicycle Rolling Resistance: Tire Rolling Resistance Tests and More

#81

Post by wiredfool »

ActorNightly wrote: post #68
scott_w wrote: post #60

Earlier quoted context omitted.

> a narrower tire is going to usually be better, because you gain the aerodynamic advantage Testing has shown this to not be true. Width is less important than overall shape of the tyre/wheel/bicycle interface when it comes to aerodynamics.

Then everyone in the peloton for races like Paris Roubaix would be on 38c gravel tires. The reason they run 28c is because while it sucks for cobblestone, there sre flatter sections where the aero advantage is worth it. Per 10mm tire width increase, you are getting 10 watts more aero drag at 25 mph.

Van der Pol won on 32mm tires this year, vs his normal 28mm.

32 also happens to be the biggest tire that fits in his Canyon race bike.

Re: Bicycle Rolling Resistance: Tire Rolling Resistance Tests and More

#82

Post by wiredfool »

pmontra wrote: post #52
ActorNightly wrote: post #25

Earlier quoted context omitted.

>Unless you're on the ProTour You don't have to be on the Pro Tour to benefit from aero gains with narrower tires. Even moderately fit people usually can sustain 15 mph on flat, at which point aero gains start to matter. Even more for hilly terrain where you can easily pick up over 20 mph on descents. The wider tires roll more efficient at lower psi (when you have to air down for comfort). But roughness of pavement r…

28 mm tires used to be huge tires. Pros didn't ride anything wider than 23 mm in the 90s. 25 mm would be for special occasions. 21 mm on tracks, sometimes even 19 mm. I think than Valverde used a 28 mm in a Roubaix and at the end of the race said that it was too much and not worth of the extra weight and front section. Every pro is riding on 30 or 32 mm now. Of course the rims are totally different and wrap those tir…

I bet if you ran the same tires in 42 and 28, you'd be basically at the same speed, at least on smooth roads.

Re: Bicycle Rolling Resistance: Tire Rolling Resistance Tests and More

#83

Post by arghwhat »

ActorNightly wrote: post #71
arghwhat wrote: post #31

Earlier quoted context omitted.

On descents you can also pick up a lot of speed by getting a heavier bike and supersizing your meals at McDonalds. Speed on descents isn't really that relevant - you're descending, so unless you're racing it's practically effort-less. What matters for people biking normally (i.e., not recreational road bike racing) is assistance in the 10-15mph regime, on flat terrain or climbing. Large changes in rolling resistance…

Yes if you bike slowly, wider tires are better. However I mentioned that in my post. A lot of people who are into biking are in the fitness zone where they are going into speeds where aero starts to matter way more. This is especially true when you consider wind.

Quoting the article posted in another comment (https://www.renehersecycles.com/12-myths-in-cycling-1-wider-...)

> The German magazine TOUR built a sophisticated setup with a motorized dummy rider and found that a 28 mm-wide tire had the same wind resistance as a 25 mm tire when the wind was coming from straight ahead. With a crosswind, the wider tire was very slightly less aerodynamic. Even then, the wider tires required only 5 watt more – on real roads, the reduced suspension losses make up for that.

> To summarize all this research: Narrow tires (<25 mm) are slow. Above 25 mm, the width of your tires are won't change your speed on smooth pavement (at least up to 54 mm wide tires). On rough surfaces, wider tires are faster. That doesn't mean you can just slap any wide tires on your bike and expect it to go fast.

Re: Bicycle Rolling Resistance: Tire Rolling Resistance Tests and More

#84

Post by uxp100 »

cogman10 wrote: post #76
303uru wrote: post #66

Earlier quoted context omitted.

As a cyclist, this is a situation in which I find this type of reviewing close to worthless to be honest. Throwing a tire on a metal roller is very far removed from riding unless you're on a velodrome or perfectly maintained road. This has led to a lot of push-back in the cycling community against this site and its findings. Their testing methodology, especially before they made recent changes, largely will prefer sk…

To add to this, unless you are actually competitively cycling (you probably aren't) this sort of thing makes pretty much no difference for someone that is using cycling for transport. It's a bit like obsessing over the lightest frame possible. Yeah, we can get a 1lb frame made of space materials but at the end of the day it's basically something that will reduce a cyclist's average speed by like 0.1mph. For anyone do…

I think it’s a little different than bike weight, which makes very little difference for anything other than lifting it onto a rack or taking it up apartment stairs. Rolling resistance makes slightly more difference than that.

Re: Bicycle Rolling Resistance: Tire Rolling Resistance Tests and More

#85

Post by scott_w »

ActorNightly wrote: post #68
scott_w wrote: post #60

Earlier quoted context omitted.

> a narrower tire is going to usually be better, because you gain the aerodynamic advantage Testing has shown this to not be true. Width is less important than overall shape of the tyre/wheel/bicycle interface when it comes to aerodynamics.

Then everyone in the peloton for races like Paris Roubaix would be on 38c gravel tires. The reason they run 28c is because while it sucks for cobblestone, there sre flatter sections where the aero advantage is worth it. Per 10mm tire width increase, you are getting 10 watts more aero drag at 25 mph.

Gravel tyres have higher rolling resistance. Also, beyond 32mm, you start risking cornering ability on the road as there’s more tyre to roll over to change direction.

Aero drag is just not that simple. You can’t, without testing, make the claim you’re making. Also, you can’t make the claim outside of the exact setup you tested. A different rider, wheels or bike could test faster on 40mm because aerodynamic drag is that difficult to predict.

Re: Bicycle Rolling Resistance: Tire Rolling Resistance Tests and More

#86

Post by scott_w »

pbhjpbhj wrote: post #63
scott_w wrote: post #14

Earlier quoted context omitted.

I just explained it in my message: you pay once for a year and that's it. This is not a lifetime access, it's a one-off payment that gives you access for 12 months. If you like it, you purchase again. I really don't understand how this is confusing for you.

>"If you like it, you purchase again." This is not what I would call a one-time payment. If you wish to continue to use the website you pay again. That's just not what "one-time" means to me. It's not confusing, it's just annoying marketing-speak in the sense that (paraphrasing) 'a simple one-time payment' is what customers like when purchasing something. Whereas the offer is not that, the term has been used in any c…

I understand your thinking, it’s just inconsistent with the rest of the world’s understanding of the words.

Re: Bicycle Rolling Resistance: Tire Rolling Resistance Tests and More

#87

Post by fenazego »

wffurr wrote: post #46
pandemic_region wrote: post #22

Unless you're on the ProTour, choose riding comfort over rolling resistance. Also see https://www.renehersecycles.com/12-myths-in-cycling-1-wider-... for a related myth-debunking of the impact of tire width (which contributes to rolling resistance) on speed.

I choose flat resistance over either. Schwalbe Marathons or equivalent on all my bikes, but I use my bikes as my primary mode of transportation in the city. I really don’t want to deal with flats when I have to be on time. Edit: after browsing the site, the Marathons are the lowest rolling resistance touring tires too! Double bonus for an excellent tire, which I can now recommend without reservations.

I like the Marathons for the same reasons. Only in cold weather it‘s like the rubber of the tyres gets quite a bit stiffer (more so than other tyres), and provides less grip, just when you need it.

Re: Bicycle Rolling Resistance: Tire Rolling Resistance Tests and More

#88

Post by tim333 »

uxp100 wrote: post #84
cogman10 wrote: post #76

Earlier quoted context omitted.

To add to this, unless you are actually competitively cycling (you probably aren't) this sort of thing makes pretty much no difference for someone that is using cycling for transport. It's a bit like obsessing over the lightest frame possible. Yeah, we can get a 1lb frame made of space materials but at the end of the day it's basically something that will reduce a cyclist's average speed by like 0.1mph. For anyone do…

I think it’s a little different than bike weight, which makes very little difference for anything other than lifting it onto a rack or taking it up apartment stairs. Rolling resistance makes slightly more difference than that.

Yeah. Between two brands of racing tyre the difference may be small but between racing tyres and some mountain bike tyres there's a very noticeable difference.

Re: Bicycle Rolling Resistance: Tire Rolling Resistance Tests and More

#89

Post by YuukiRey »

ActorNightly wrote: post #25
pandemic_region wrote: post #22

Unless you're on the ProTour, choose riding comfort over rolling resistance. Also see https://www.renehersecycles.com/12-myths-in-cycling-1-wider-... for a related myth-debunking of the impact of tire width (which contributes to rolling resistance) on speed.

>Unless you're on the ProTour You don't have to be on the Pro Tour to benefit from aero gains with narrower tires. Even moderately fit people usually can sustain 15 mph on flat, at which point aero gains start to matter. Even more for hilly terrain where you can easily pick up over 20 mph on descents. The wider tires roll more efficient at lower psi (when you have to air down for comfort). But roughness of pavement r…

Aero also matters at low speeds since you spend more time on the course

Re: Bicycle Rolling Resistance: Tire Rolling Resistance Tests and More

#90

Post by ciupicri »

cogman10 wrote: post #76
303uru wrote: post #66

Earlier quoted context omitted.

As a cyclist, this is a situation in which I find this type of reviewing close to worthless to be honest. Throwing a tire on a metal roller is very far removed from riding unless you're on a velodrome or perfectly maintained road. This has led to a lot of push-back in the cycling community against this site and its findings. Their testing methodology, especially before they made recent changes, largely will prefer sk…

To add to this, unless you are actually competitively cycling (you probably aren't) this sort of thing makes pretty much no difference for someone that is using cycling for transport. It's a bit like obsessing over the lightest frame possible. Yeah, we can get a 1lb frame made of space materials but at the end of the day it's basically something that will reduce a cyclist's average speed by like 0.1mph. For anyone do…

I've switched to Schwalbe Marathon Almotion from some knobby Kenda and they made a night and day difference. It was a pleasure to ride in the city.
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