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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

#131

Post by bluecalm »

pandaman wrote: post #99
bluecalm wrote: post #36

Earlier quoted context omitted.

Gravel bikes are going to transform in coming years as now they are neither very comfortable nor fast. It turns out that wider MTB tires are both faster (when it comes to rolling resistance) and way more comfortable and safer than gravel tires even on tarmac, let alone any kind of terrain. The reason is that soft casing is way more important than knobs when it comes to rolling resistance and MTB tires can be made sof…

Gravel bikes are much more comfortable and fast than road bikes on unpaved roads, which is what they are designed for. Wider wheels will add more weight and more angular momentum, making it harder to climb and harder to steer so you might need to replace the drop bar with the MTB flat bar and without the drops you can move the saddle into a more comfortable position as well... ending with a hardtail w/o the suspensio…

Fast MTB tires are like 100g heavier than current crop of gravel tires. Not a big penalty as they roll much faster and are have much better grip.

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

#132

Post by pandaman »

bluecalm wrote: post #131
pandaman wrote: post #99

Earlier quoted context omitted.

Gravel bikes are much more comfortable and fast than road bikes on unpaved roads, which is what they are designed for. Wider wheels will add more weight and more angular momentum, making it harder to climb and harder to steer so you might need to replace the drop bar with the MTB flat bar and without the drops you can move the saddle into a more comfortable position as well... ending with a hardtail w/o the suspensio…

Fast MTB tires are like 100g heavier than current crop of gravel tires. Not a big penalty as they roll much faster and are have much better grip.

40 mm tires are ~500g, what kind of 600g MTB tires you have in mind?

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

#133

Post by l1tany11 »

pandaman wrote: post #132
bluecalm wrote: post #131

Earlier quoted context omitted.

Fast MTB tires are like 100g heavier than current crop of gravel tires. Not a big penalty as they roll much faster and are have much better grip.

40 mm tires are ~500g, what kind of 600g MTB tires you have in mind?

Kenda booster & rush. Continental race king. Maxxis Aspen & Aspen ST. Schwalbe RRs, Vittoria Mezcal, S-works Renegade & fast track, Pirelli Scorpion. Basically every MTB tire manufacturer makes an XC race tire in the 600g range. Some are below 600g, some are above 600g (but below 700g). Just look at the list on the website this thread is under.

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

#134

Post by pandaman »

l1tany11 wrote: post #133
pandaman wrote: post #132

Earlier quoted context omitted.

40 mm tires are ~500g, what kind of 600g MTB tires you have in mind?

Kenda booster & rush. Continental race king. Maxxis Aspen & Aspen ST. Schwalbe RRs, Vittoria Mezcal, S-works Renegade & fast track, Pirelli Scorpion. Basically every MTB tire manufacturer makes an XC race tire in the 600g range. Some are below 600g, some are above 600g (but below 700g). Just look at the list on the website this thread is under.

But these do not show amazing rolling resistance on that site either. Only Race King approaches top RR numbers of the gravel tires. There are plenty of sub 400g gravel tires with less RR than these. As far as I understood my correspondent, he predicts that riders will add angular momentum (when and MTB riders already complain about steering on gravel bikes) and, apparently, won't win any rolling resistance. What for? Riding at even lower pressure? To do what?

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

#135

Post by ActorNightly »

arghwhat wrote: post #83
ActorNightly wrote: post #71

Earlier quoted context omitted.

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 re…

25 and 28 are basically same width. Also wind tunnel testing is not really representative of real world condition given real world turbulence, but I dunno if that would really affect results.

Im just against the general saying that wider tires are faster. This implies that fat bike smooth tires are the fastest, but we know that this is ridiculous. 25 to 35c probably doesn't matter too much aero wise at regular cycling speeds, but going all the way into 40-50c does.

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

#136

Post by ActorNightly »

wiredfool wrote: post #81
ActorNightly wrote: post #68

Earlier quoted context omitted.

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.

You are right, this year 32c seems to be the most common. I remember 2023 was still 28c, and there were tests done that I remember seeing where 28c was slightly more efficient than 30c, but at a higher pressure.

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

#137

Post by ActorNightly »

wiredfool wrote: post #82
pmontra wrote: post #52

Earlier quoted context omitted.

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.

You cant really pump up 42c tires to 100 psi safely, so no.

Remember that the wider tires are more efficient at lower pressures than narrower tires. However as the pressures go up, the difference becomes smaller. Even without aero gains, the narrower tire will be faster provided its a smooth surface.

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

#138

Post by ActorNightly »

basil-rash wrote: post #101
ActorNightly wrote: post #78

Earlier quoted context omitted.

Same fitness on a more efficient bike = longer distance or higher speed.

To what end?

Lots of factors. For example, i get way less tired riding a road bike in the heat than a mountain bike, because the airflow at speed helps me keep cool.

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

#139

Post by pmontra »

seadan83 wrote: post #116
bennyelv wrote: post #112

Earlier quoted context omitted.

I hear what you're saying and that would normally make sense, but there are reasons why I don't think its true in the bike industry. It comes down to the same arguments that you often see on HN about whether or not a free market works. Shimano can decide to stop manufacturing rim brake groupsets and spares for existing rim brake groupsets unilaterally. It doesn't matter if the customer wants it or not. The rest of th…

If shimano stopped making rim brakes, no tour de France athlete would use shimano groupsets. Rim brakes are lighter, that is why. Would shimano ever give that up? No. All these companies pride themselves for being what the elites run. Dura ace would become a joke if no elites used it. The dura ace groupo upgrade is thousands of dollars (2k to be exact, it's the most expensive 100g you can pay for), & dura ace is high…

Your points about the zillions of rim brakes bikes sold at 100-300 Euro price points are definitely on spot. They don't need performance, those brakes are very cheap, they are easy to maintain, they'll last forever in the market IMHO.

However I'm not sure I understood your first point about disc vs rim brakes. Rim brakes are lighter but disc brakes brake better, in a shorter span and under any circumstance, even in the rain when the rim is wet and a rim brake takes a little to warm up and make friction on the rim. Furthermore wheels and bikes are at 6.8 kg even with disc brakes now. That's why every pro rider started using them when they had a choice. There was a short while when they were kept at hold because of concerns that the disc could hurt riders in group crashes (they don't have that problem in cyclocross or MTB,) then concerns about weight and aero, but given the average speeds they are doing at the Giro in these days I'd say that it is all well in the past.

I'm no tour de France rider but on a steep and long slope I rather use my disc brakes than the rim brakes of my previous bicycle. It was a good bike with much better brakes than the vbrakes of the bike I use for touring with bags but disc brakes are on a different level.

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

#140

Post by mnky9800n »

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 always enjoy those conversations with middle aged cyclist who fill up their jersey and then talk about how they shaved off 200g somewhere. Dude if you didn't drink all those after ride beers you could shave off a lot more than 200g. This is why I refuse to wear jerseys. Ahahaha.
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