How much of a difference does tire width make on road bike performance?
#26
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tire size doesn't play as much a role in your cornering performance, it's the rubber softness that matters, and plenty of progressively faster practices so you get the feeling of approaching the edge of mechanical grip.
here's a video of a guy absolutely railing on 23mm tires at high speed
https://www.youtube.com/watch?v=hkc-...&index=24&t=0s
here's a video of a guy absolutely railing on 23mm tires at high speed
https://www.youtube.com/watch?v=hkc-...&index=24&t=0s
#27
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#28
if using a good quality road bike frame with not so beefy carbon fork i would be alright with 28mm tires.
i did ride a Scapin EOS 7 that had a woundup fork. it could not fit more than 28mm tires. i was alright with a 18-19mm inner width front rim.
last road-ish bike i used was a chopped up CX that had oversized tubing with 35mm/37mm front/rear. the rims were about 19mm inner width.
this type of frame.
now i roll on a 29er MTB with only the front brake and 1.6"/2" front/rear. rims are 21mm inner width. i miss the first bike more than i miss the second.
i did ride a Scapin EOS 7 that had a woundup fork. it could not fit more than 28mm tires. i was alright with a 18-19mm inner width front rim.
last road-ish bike i used was a chopped up CX that had oversized tubing with 35mm/37mm front/rear. the rims were about 19mm inner width.
this type of frame.
now i roll on a 29er MTB with only the front brake and 1.6"/2" front/rear. rims are 21mm inner width. i miss the first bike more than i miss the second.
#29
and then you say wider tire gives larger contact patch and thus is safer in cornering?? I wonder how much you really know about science?
First of all, skinnier tire doesn't mean smaller contact patch area, but a different contact patch profile.
Secondly, bigger contact patch doesn't mean higher mechanical grip in corners, because mechanical grip almost entirely rely on rubber type. This is the reason why MotoGP front tires are smaller than their rears while still providing tremendous mechanical grip (because they use softer rubber).
Lastly, I posted a youtube video of a guy on 23mm tires railing at speed that I'm sure nobody in here with their wider tires will come even close. So please stop the nonsense.
There are legit cases of using wider tires for comfort and traction (which is not the same as grip) like in gravels and mtb, but please don't falsely extrapolate this use onto pavement. You're actually doing a disservice posting misleading information.
#30
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A wider tire with more volume stays round longer with a wider contact patch and is safer in cornering. I have ridden both narrow and wide tire bikes. It's a real life difference.
#32
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man, dude, you have brought up the word "science" multiple times in this thread and telling us that skinnier tires are "less efficient" (whatever efficiency means we don't know),..
and then you say wider tire gives larger contact patch and thus is safer in cornering?? I wonder how much you really know about science?
First of all, skinnier tire doesn't mean smaller contact patch area, but a different contact patch profile.
Secondly, bigger contact patch doesn't mean higher mechanical grip in corners, because mechanical grip almost entirely rely on rubber type. This is the reason why MotoGP front tires are smaller than their rears while still providing tremendous mechanical grip (because they use softer rubber).
Lastly, I posted a youtube video of a guy on 23mm tires railing at speed that I'm sure nobody in here with their wider tires will come even close. So please stop the nonsense.
There are legit cases of using wider tires for comfort and traction (which is not the same as grip) like in gravels and mtb, but please don't falsely extrapolate this use onto pavement. You're actually doing a disservice posting misleading information.
and then you say wider tire gives larger contact patch and thus is safer in cornering?? I wonder how much you really know about science?
First of all, skinnier tire doesn't mean smaller contact patch area, but a different contact patch profile.
Secondly, bigger contact patch doesn't mean higher mechanical grip in corners, because mechanical grip almost entirely rely on rubber type. This is the reason why MotoGP front tires are smaller than their rears while still providing tremendous mechanical grip (because they use softer rubber).
Lastly, I posted a youtube video of a guy on 23mm tires railing at speed that I'm sure nobody in here with their wider tires will come even close. So please stop the nonsense.
There are legit cases of using wider tires for comfort and traction (which is not the same as grip) like in gravels and mtb, but please don't falsely extrapolate this use onto pavement. You're actually doing a disservice posting misleading information.
BTW efficiency just means you lose fewer watts or however you want to measure input because of vibration dampening.
Please stop misleading the OP with poor, outdated information as it relates to relatively narrow tires.
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I've been wondering about this lately as I've switched from 26x1.5 to 26x1.9 slicks and then 26x1.95 knobbies. The narrower tires were too painful to ride and had such unpredictable handling that I switched to the 1. 9 slicks for a few weeks. A sidewall failure got me to switch back to the 1.95 knobbies (these were all old tires I had used in the past) with my commute times being about the same and some surprising readings of the speedometer when I thought I was just plodding along. The wider tires use less pressure too, now that we know lower pressures don't mean less speed does anyone know how to figure out what pressures to use? I had been using the maximum listed on the tires for both front and rear before fwiw.
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The key is supple and light. And for this old rider, those old retro tire savers that scrape the debris from the tread, to minimize flats. They have worked for me for 45 years. https://www.renehersecycles.com/tire-wipers/
Still no flats on my Conti GP4000SII 28s or my Compass/Rene Herse 28 and 32mm standard casing tires. Plus never a flat through the tread on tubulars in my much younger days.
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#35
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I've been wondering about this lately as I've switched from 26x1.5 to 26x1.9 slicks and then 26x1.95 knobbies. The narrower tires were too painful to ride and had such unpredictable handling that I switched to the 1. 9 slicks for a few weeks. A sidewall failure got me to switch back to the 1.95 knobbies (these were all old tires I had used in the past) with my commute times being about the same and some surprising readings of the speedometer when I thought I was just plodding along. The wider tires use less pressure too, now that we know lower pressures don't mean less speed does anyone know how to figure out what pressures to use? I had been using the maximum listed on the tires for both front and rear before fwiw.
Generally, the wider rim you have will prevent pinch flats. You can try it out on your shop floor, experiment with different pressures, hop on and see how much your sidewall gives. You'll be more efficient with less air, but you can't bottom out either so it is a juggling act.
FWIW I am guessing if you can run 26*1.9 you can probably squeeze in 26*2.25 or even 2.35 with no or little tread. I know there are a lot of quality slick tires in that size right now which are worth a shot. Don't worry about tread design, just go with a slick or semi slick tire with the max width and highest TPI you can find. Tubeless is even better as you have no tube to pinch but that's a different thread :-)
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the larger the tire + lower pressure = more rubber on the road. All things being equal, the more rubber touching the road the more traction, grip, whatever you want to call it, will result. In the real world, this always holds true because the area which makes contact with the road is often touching several uneven surfaces and different objects all at one time, so the more rubber you can put on the road, the more rubber which will FIND the road and adhere to it. I live in the real world, not in a lab or velodrome, or closed course so I am interested in what ACTUALLY works.
Sure, the tires in the vid are made of high quality rubber; the rider would have an even better experience descending on very wide, properly inflated tires with the same compound.
Sure, the tires in the vid are made of high quality rubber; the rider would have an even better experience descending on very wide, properly inflated tires with the same compound.
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I don't really see a lot of difference anywhere from 23 to 32, honestly. Some people are really excited about this though.
#40
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And you probably won't until you go north of 50. 32 is too narrow for most of us on here, although the spandex-clad, TDF wannabe crowd will argue that's too wide
#41
You are mistaken - the benefits of wider tires apply to every riding surface except for velodromes. Wider tires allow for better traction, grip, whatever you want to call it, all other things being equal (rubber compound etc). The research is out there which supports this position. Everyone is just afraid of showing up on to their Saturday AM group ride with a non-conforming bike.
BTW efficiency just means you lose fewer watts or however you want to measure input because of vibration dampening.
Please stop misleading the OP with poor, outdated information as it relates to relatively narrow tires.
BTW efficiency just means you lose fewer watts or however you want to measure input because of vibration dampening.
Please stop misleading the OP with poor, outdated information as it relates to relatively narrow tires.
Please go here for a simple explanation of grip:
Friction Formula
"contact patch size" doesn't come into the equation of grip, it's in fact all dependent on the frictional coefficient of the rubber.
Somtimes, intuitions can get you into trouble. Here's something to think about friction and grip.
Let us suppose that we're sliding a square block of ice across the floor. The block of ice has certain contact-patch area with the floor.
Now, suppose we cut the block of ice into 2 halves so now that each half has 1/2 the contact-patch area of the original block.
Question: so do the 2 smaller blocks have less friction grip than the original larger block? The answer is no. All three blocks have exactly the same frictional grip. In other words, grip does not depend on the size of the contact-patch at all.
Now, there are reason why you'd want to use a larger tire (for traction, longevity, etc), but "larger contact patch gives better grip" is not one of them. I'm merely pointing out your false fact that you seem to hell bent on embracing, and doing the community a disservice. I hope you get this.
#42
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I'm afraid you really don't know what you're talking about. You don't understand traction, grip, and rubber.
Please go here for a simple explanation of grip:
Friction Formula
"contact patch size" doesn't come into the equation of grip, it's in fact all dependent on the frictional coefficient of the rubber.
Somtimes, intuitions can get you into trouble. Here's something to think about friction and grip.
Let us suppose that we're sliding a square block of ice across the floor. The block of ice has certain contact-patch area with the floor.
Now, suppose we cut the block of ice into 2 halves so now that each half has 1/2 the contact-patch area of the original block.
Question: so do the 2 smaller blocks have less friction grip than the original larger block? The answer is no. All three blocks have exactly the same frictional grip. In other words, grip does not depend on the size of the contact-patch at all.
Now, there are reason why you'd want to use a larger tire (for traction, longevity, etc), but "larger contact patch gives better grip" is not one of them. I'm merely pointing out your false fact that you seem to hell bent on embracing, and doing the community a disservice. I hope you get this.
Please go here for a simple explanation of grip:
Friction Formula
"contact patch size" doesn't come into the equation of grip, it's in fact all dependent on the frictional coefficient of the rubber.
Somtimes, intuitions can get you into trouble. Here's something to think about friction and grip.
Let us suppose that we're sliding a square block of ice across the floor. The block of ice has certain contact-patch area with the floor.
Now, suppose we cut the block of ice into 2 halves so now that each half has 1/2 the contact-patch area of the original block.
Question: so do the 2 smaller blocks have less friction grip than the original larger block? The answer is no. All three blocks have exactly the same frictional grip. In other words, grip does not depend on the size of the contact-patch at all.
Now, there are reason why you'd want to use a larger tire (for traction, longevity, etc), but "larger contact patch gives better grip" is not one of them. I'm merely pointing out your false fact that you seem to hell bent on embracing, and doing the community a disservice. I hope you get this.
Let's look at race cars - do dragsters and F1 cars have relatively wide tires or narrow ones? Not a perfect analogue for bikes but a lot closer than freaking ice blocks.
Wider tires are becoming the norm and the industry will fully embrace these ideas because they're safer and more efficient. You are free to cling just as tightly to your ideas as you wish. It's a free country (for now)
#43
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I've been wondering about this lately as I've switched from 26x1.5 to 26x1.9 slicks and then 26x1.95 knobbies. The narrower tires were too painful to ride and had such unpredictable handling that I switched to the 1. 9 slicks for a few weeks. A sidewall failure got me to switch back to the 1.95 knobbies (these were all old tires I had used in the past) with my commute times being about the same and some surprising readings of the speedometer when I thought I was just plodding along. The wider tires use less pressure too, now that we know lower pressures don't mean less speed does anyone know how to figure out what pressures to use? I had been using the maximum listed on the tires for both front and rear before fwiw.
To figure it out - I just ride them at different pressures. I can let my tires reach embarrassingly low pressures - I don't often get pinch flats - and I notice at a certain point that I'm losing speed. At the other end, I gradually drop the fill-up pressure until the whole ride feels decently smooth (just a lap around the parking lot isn't enough). Everything in between those two is OK, find the "best" point by feel.
#44
The idea that less rubber on the road results in higher grip is asinine. Ice blocks do not explain the forces at work here, they slip on surfaces because of the layer of water between the ice and the other surface. Rubber doesn't work like this.
Let's look at race cars - do dragsters and F1 cars have relatively wide tires or narrow ones? Not a perfect analogue for bikes but a lot closer than freaking ice blocks.
Wider tires are becoming the norm and the industry will fully embrace these ideas because they're safer and more efficient. You are free to cling just as tightly to your ideas as you wish. It's a free country (for now)
Let's look at race cars - do dragsters and F1 cars have relatively wide tires or narrow ones? Not a perfect analogue for bikes but a lot closer than freaking ice blocks.
Wider tires are becoming the norm and the industry will fully embrace these ideas because they're safer and more efficient. You are free to cling just as tightly to your ideas as you wish. It's a free country (for now)
I'm glad you asked me about F1 and dragsters. The reason why high high performance sports cars use wider and thicker is:
1. to support their weight
2. for longevity
If a dragster were to use a small tire, it would shred the tire in pieces. However, the rubber of these high performance cars are in fact pretty soft at operating temperature. And it's the softness of these tires (ie, high coefficient of friction) that give the tire their grip, not because they are wide. Wideness is for weight support.
I posted a link for formula showing that mechanic grip depends on coefficient of friction and not contact patch. Did you look at that? I reckon you didn't because you keep spewing the same nonsense?
Another way of thinking of it is this. If somehow tire manufacturer is able to construct a carcass in a smaller tire that could support the weight of these cars, then they would use smaller tires for aero and acceleration advantage.
my dude, this is not about any free country, it's about physics, and honestly you're just very ignorant. I'm not to debate with you anymore because there is nothing more I can say if you don't understand 2+2=4!
Last edited by aclinjury; 09-30-19 at 08:10 PM.
#45
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The idea that less rubber on the road results in higher grip is asinine. Ice blocks do not explain the forces at work here, they slip on surfaces because of the layer of water between the ice and the other surface. Rubber doesn't work like this.
Let's look at race cars - do dragsters and F1 cars have relatively wide tires or narrow ones? Not a perfect analogue for bikes but a lot closer than freaking ice blocks.
Wider tires are becoming the norm and the industry will fully embrace these ideas because they're safer and more efficient. You are free to cling just as tightly to your ideas as you wish. It's a free country (for now)
Let's look at race cars - do dragsters and F1 cars have relatively wide tires or narrow ones? Not a perfect analogue for bikes but a lot closer than freaking ice blocks.
Wider tires are becoming the norm and the industry will fully embrace these ideas because they're safer and more efficient. You are free to cling just as tightly to your ideas as you wish. It's a free country (for now)
You would think that after oh, 120 years or so of Paris Roubaix, if running 2.0 inch tires made them faster and more efficient, everyone would be riding 2.0 inch tires by now.
Hell, they tried everything else.
Alas, no.
The Hour Record has been around even longer and I'm pretty damn sure if wider tires meant faster and more efficient they would have done it by now.
You think tradition or image keeps folks on skinny tires?
I don't see anyone setting records on fat tires.
Money makes the world go round and no one is winning on 38s.
If running wider tires meant faster, the FIRST guys on them would be the PROs.
I don't see no one in the peloton riding 29er tires.
And by the way, F1 tires have actually gotten smaller.
Oh and I might be more open to your theories if you had any actual evidence.
Last edited by jideta; 09-30-19 at 08:19 PM.
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#46
Dude, your theories, or whatever you want to call it, are just that: whatever you want to call it.
You would think that after oh, 120 years or so of Paris Roubaix, if running 2.0 inch tires made them faster and more efficient, everyone would be riding 2.0 inch tires by now.
Hell, they tried everything else.
Alas, no.
The Hour Record has been around even longer and I'm pretty damn sure if wider tires meant faster and more efficient they would have done it by now.
You think tradition or image keeps folks on skinny tires?
I don't see anyone setting records on fat tires.
Money makes the world go round and no one is winning on 38s.
If running wider tires meant faster, the FIRST guys on them would be the PROs.
I don't see no one in the peloton riding 29er tires.
And by the way, F1 tires have actually gotten smaller.
Oh and I might be more open to your theories if you had any actual evidence.
You would think that after oh, 120 years or so of Paris Roubaix, if running 2.0 inch tires made them faster and more efficient, everyone would be riding 2.0 inch tires by now.
Hell, they tried everything else.
Alas, no.
The Hour Record has been around even longer and I'm pretty damn sure if wider tires meant faster and more efficient they would have done it by now.
You think tradition or image keeps folks on skinny tires?
I don't see anyone setting records on fat tires.
Money makes the world go round and no one is winning on 38s.
If running wider tires meant faster, the FIRST guys on them would be the PROs.
I don't see no one in the peloton riding 29er tires.
And by the way, F1 tires have actually gotten smaller.
Oh and I might be more open to your theories if you had any actual evidence.
#47
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I used a block of ice. But the principle would apply to a block of cement or a block of rubber. This is simply a physics principle. I did not make this up.
I'm glad you asked me about F1 and dragsters. The reason why high high performance sports cars use wider and thicker is:
1. to support their weight
2. for longevity
If a dragster were to use a small tire, it would shred the tire in pieces. However, the rubber of these high performance cars are in fact pretty soft at operating temperature. And it's the softness of these tires (ie, high coefficient of friction) that give the tire their grip, not because they are wide. Wideness is for weight support.
I posted a link for formula showing that mechanic grip depends on coefficient of friction and not contact patch. Did you look at that? I reckon you didn't because you keep spewing the same nonsense?
Another way of thinking of it is this. If somehow tire manufacturer is able to construct a carcass in a smaller tire that could support the weight of these cars, then they would use smaller tires for aero and acceleration advantage.
my dude, this is not about any free country, it's about physics, and honestly you're just very ignorant. I'm not to debate with you anymore because there is nothing more I can say if you don't understand 2+2=4!
I'm glad you asked me about F1 and dragsters. The reason why high high performance sports cars use wider and thicker is:
1. to support their weight
2. for longevity
If a dragster were to use a small tire, it would shred the tire in pieces. However, the rubber of these high performance cars are in fact pretty soft at operating temperature. And it's the softness of these tires (ie, high coefficient of friction) that give the tire their grip, not because they are wide. Wideness is for weight support.
I posted a link for formula showing that mechanic grip depends on coefficient of friction and not contact patch. Did you look at that? I reckon you didn't because you keep spewing the same nonsense?
Another way of thinking of it is this. If somehow tire manufacturer is able to construct a carcass in a smaller tire that could support the weight of these cars, then they would use smaller tires for aero and acceleration advantage.
my dude, this is not about any free country, it's about physics, and honestly you're just very ignorant. I'm not to debate with you anymore because there is nothing more I can say if you don't understand 2+2=4!
And don't worry, you obviously lack the chops to debate with me! The friction equation doesn't control for NUMEROUS variables at work in a tire's interaction with the road in real-life conditions.
#48
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Dude, your theories, or whatever you want to call it, are just that: whatever you want to call it.
You would think that after oh, 120 years or so of Paris Roubaix, if running 2.0 inch tires made them faster and more efficient, everyone would be riding 2.0 inch tires by now.
Hell, they tried everything else.
Alas, no.
The Hour Record has been around even longer and I'm pretty damn sure if wider tires meant faster and more efficient they would have done it by now.
You think tradition or image keeps folks on skinny tires?
I don't see anyone setting records on fat tires.
Money makes the world go round and no one is winning on 38s.
If running wider tires meant faster, the FIRST guys on them would be the PROs.
I don't see no one in the peloton riding 29er tires.
And by the way, F1 tires have actually gotten smaller.
Oh and I might be more open to your theories if you had any actual evidence.
You would think that after oh, 120 years or so of Paris Roubaix, if running 2.0 inch tires made them faster and more efficient, everyone would be riding 2.0 inch tires by now.
Hell, they tried everything else.
Alas, no.
The Hour Record has been around even longer and I'm pretty damn sure if wider tires meant faster and more efficient they would have done it by now.
You think tradition or image keeps folks on skinny tires?
I don't see anyone setting records on fat tires.
Money makes the world go round and no one is winning on 38s.
If running wider tires meant faster, the FIRST guys on them would be the PROs.
I don't see no one in the peloton riding 29er tires.
And by the way, F1 tires have actually gotten smaller.
Oh and I might be more open to your theories if you had any actual evidence.
The PR and Hour Record are perfect examples of the point I am making: narrow tires are good in CONTROLLED RACING conditions - where you're either on a velodrome or a sprint finish situation is anticipated to win. These ideas are deeply ingrained in cycling design, which is a shame. If guys like you could give up your wet dreams of competing in a Grand Tour, then we'd probably all have more efficient, safer bikes on the market. Thankfully, some manufacturers are taking note and making bikes with wider tires and shorter stems/top tubes despite industry (and mostly aesthetic) norms.
It's a shame most guys like you buy bikes and tires based on what the A Group on your Saturday AM ride thinks and not what actually works out here in the real world.
#49
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I'm now vaguely curious to see if they still make 700c21s, which were apparently popular back when people thought narrow tires were the way to go. Kinda want to try them for fun.
also F1 tire width is generally down to regulations, and not any sort of ideal-tire-width development
also F1 tire width is generally down to regulations, and not any sort of ideal-tire-width development
Last edited by sheddle; 10-01-19 at 08:33 AM.
#50
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I'm now vaguely curious to see if they still make 700c21s, which were apparently popular back when people thought narrow tires were the way to go. Kinda want to try them for fun.
also F1 tire width is generally down to regulations, and not any sort of ideal-tire-width development
also F1 tire width is generally down to regulations, and not any sort of ideal-tire-width development
In fact, the only time narrow tires are used are on the FRONT in drag cars, because they don't NEED good traction in that position, they need to be light and spin up quickly, same reason narrow tires are used on road racing bikes.
I am sure I have seen 21mm, maybe even 19mm tires. Might be a fun experiment on a very smooth surface for curiosity-sake but wouldn't want to ride any sort of distance on them.