vvill’s N + 1 Pointless Prize

[Subby]

That’s really interesting. So I guess folks run 23s just out of habit? Is there a handling component to skinnier tires or is that just imagined as well?

[TwoWheelsDC]

@Subby 136711 wrote:

That’s really interesting. So I guess folks run 23s just out of habit? Is there a handling component to skinnier tires or is that just imagined as well?

They are aerodynamically better, although I’d wager you have to be over 20mph for it to be a factor. I like 23s because they *feel* faster, which is probably just due to them being less cushy and transmitting more vibrations, but I like the feel of it. I also prefer them aesthetically.

[hozn]

@TwoWheelsDC 136721 wrote:

They are aerodynamically better, although I’d wager you have to be over 20mph for it to be a factor. I like 23s because they *feel* faster, which is probably just due to them being less cushy and transmitting more vibrations, but I like the feel of it. I also prefer them aesthetically.

Yeah, I don’t know if any of the studies have normalized the units in quantifying the gain/loss of running 23mm tires vs. a wider (usu. 25mm) tire — i.e. measure any aerodynamic loss and compare the watts lost to the watts gained from the lower rolling resistance. The aerodynamics depend on the rim, of course, with more and more rims getting wider, that is probably decreasingly in favor of 23mm tires. I’d conjecture that disc brakes help too, allowing these rims [usu. carbon] to grow extra wide without worrying about clearing rim-brake calipers.

There is a small weight penalty to the wider tires, but I would expect this modest number is completely overcome by any crr and aerodynamic considerations.

Here was a recent study that Velo put together: http://velonews.competitor.com/where-the-rubber-meets-the-road-what-makes-cycling-tires-fast

Highlights being that the fastest tire is a 26mm [tubeless] Specialized tire. Also illustrative here is the difference between the Schwalbe One in 25mm and 23mm — the 23mm costs 2.7 watts additional power [compared to the 25mm]. (Unfortunately they don’t have size comparisons for that many tire models in that study.) To put that in some context, a set of triathlete wheels apparently saves around 10 watts [compared to more typical road wheels].

So, yeah, there isn’t really any reason to run them other than tradition. I’d hazard a guess that we are probably in the twilight of 23mm tires.

That all said, I’m running 23mm tires right now on my road bike. There isn’t really any reason other than this is what was available/on-sale. And I have a set of 23mm tubeless tires to run after these are done, so I’ll be riding 23mm for awhile on that bike. I don’t even think it feels faster, but I do kinda like the extra road feel on that bike.

[vvill]

@hozn 136722 wrote:

I don’t even think it feels faster, but I do kinda like the extra road feel on that bike.

While I tend to run 25-28mm tires myself, I think there is certainly a case for road feel and factors like stiffness during acceleration/sprinting. A lot of these tests are done in quite static environments e.g. 1 hr at 40kph on a roller, or a wind tunnel with a preset list of yaw angles. In the real world there is a lot more acceleration (although arguably less in time trials, triathlons, some track cycling, etc.) and you are putting different stresses on your bike all the time. My gut feel is that narrower tires are easier to accelerate from because there’s less deflection (higher pressure). At those higher rider output times you don’t really want deflection – especially the front tire if you are out of the saddle. Somehow I feel like the rear tire doesn’t matter as much since you are going to have the pressure up higher than the front anyway. I also feel like since the front wheel/tire does not transit power (it just rolls over the surface) it doesn’t matter as much if it’s narrower/higher pressure and skipping along the surface a bit more (at least in terms of speed – not grip!). But I’m not sure if my gut feelings there are logically sound (FWIW I run 23 front/28 rear on my fixed gear).

I would be curious to see the results if they built a robot that could sprint out of the saddle from 0mph to 30mph, or from 25mph to 40mph, etc. with constant wattage curves and then just swap out tires and see if wider tires win there too. If I’m cruising at 16mph, then want to go up to 25mph as fast as possible I still feel like I’d rather have a 25mm up front than a 28mm (assuming I’m on smooth tarmac – not cobblestones, nor say, the trollheim bridges).

One really interesting source of bicycle research is Jan Heine:
https://janheine.wordpress.com/
He’s the guy behind Compass tires and has been ahead of much of the industry in terms of championing wider tires, lower pressure and even the benefits of non-slick treads.

[KayakCyndi]

N=17 dkel’s Surly Straggler
3/15/2016
https://www.strava.com/activities/517592544

This morning’s N+1 showed up at Cafe Kindred just in time for me to take it for a quick spin. Dkel’s straggler was the first bike I had ridden that really was just to big for me. Sitting on the seat and actually pedaling wasn’t really an option so this test ride took place standing, standing on legs that were already dead from Tuesday morning hills and Sunday’s rainy brevet.

The Straggler is a pretty bike. That shiny, sparkling purple color is just about the shade of the early blooming cherry trees in the neighborhood. Dkel must also have a thing for clean chains as his was grit free too. Maybe it has something to do with the long fenders he is running. I think the front one almost hits ground! Again this bike had a fairly upright position which shortened the ETT enough for me to be able to actually reach the bars. His bell is a thing of beauty.

[KayakCyndi]

@hozn 136420 wrote:

….
Probably Subby was just noting that the Schwalbe Durano (in any size) is a great winter tire but is not a fast tire. But having a tire that matches rim width definitely “feels right” on a road bike, I agree with that too. Assuming the Rovals are wide rims, a 25mm might work great. (Cyndi, I recommend 25mm Schwalbe One tubeless or GP4000S II if you want to stick with tubes. In which case latex tubes apparently offer improved ride — not 100% sure I could tell the difference in a blind test, but they do roll nicely.)

In other news, I moved the Duranos over to the Viaje and put some Schwalbe One’s on the Liscio. I didn’t go tubeless but got the road style 28s (http://www.schwalbetires.com/node/4318). I rode them this morning on Tuesday hills. It might be totally in my mind but they definitely seemed to roll quicker and more nicely than the Duranos. Someday I’ll get over my fear of tubeless.

[dkel]

@KayakCyndi 136760 wrote:

This morning’s N+1 showed up at Cafe Kindred just in time for me to take it for a quick spin.

Thanks for leaving it in the tallest possible gear for me to get going on my way. :rolleyes:

[KayakCyndi]

@dkel 136775 wrote:

Thanks for leaving it in the tallest possible gear for me to get going on my way. :rolleyes:

Oops. I guess when I can only pedal standing up it is easier in a taller gear!

[ShawnoftheDread]

@dkel 136775 wrote:

Thanks for leaving it in the tallest possible gear for me to get going on my way. :rolleyes:

You’re going to have to train more if you want to ride like a girl.

[dkel]

@ShawnoftheDread 136778 wrote:

You’re going to have to train more if you want to ride like a girl.

And here I thought a glittery purple bike would be enough! :p

[ginacico]

@KayakCyndi 136760 wrote:

The Straggler is a pretty bike. That shiny, sparkling purple color is just about the shade of the early blooming cherry trees in the neighborhood. Dkel must also have a thing for clean chains as his was grit free too. Maybe it has something to do with the long fenders he is running. I think the front one almost hits ground! Again this bike had a fairly upright position which shortened the ETT enough for me to be able to actually reach the bars. His bell is a thing of beauty.

I approve of dkel’s great taste in fenders

That is one very cool bike. Did it feel a little like the Vaya’s (or maybe hard to tell standing up)?

I love this thread, it’s like window shopping.

[vvill]

@dkel 136775 wrote:

Thanks for leaving it in the tallest possible gear for me to get going on my way. :rolleyes:

Better for the photos, and therefore the greater good of the forum.

[dkel]

@vvill 136785 wrote:

Better for the photos, and therefore the greater good of the forum.

She took those pics before she rode it!

[vvill]

@dkel 136787 wrote:

She took those pics before she rode it!

Well then, looks like she left it in close to the same gear as before! What’s a couple of teeth between friends?

[dkel]

@vvill 136788 wrote:

Well then, looks like she left it in close to the same gear as before! What’s a couple of teeth between friends?

To me it looks like about 30-40 gear inches difference. At least I was going downhill to start, though.

[Author]

Posts