Tire width and pressure for feather light riders

Discuss light weight issues concerning road bikes & parts.
eyedrop
Posts: 102
Joined: Wed Jan 27, 2016 5:33 am
Location: Prescott, AZ

by eyedrop

Hey guys, OP here. Glad to see this topic is still active. Lets keep the data rolling in!

Another tip for the light weight riders: You can generally get away with training on racing tires, unless your local roads are particularly bad... I only weigh 105lbs with an FTP of 170, so my tire wear rate is much lower than the average person. Ive got 700 miles on a pair of Conti Supersonic tires and they still have a good 20-30% usable life left! Ive had 2 flats with them and use them for training and racing! Not bad for being one of the fastest tires on earth at 140g and paper thin....

The only problem is it feels like cheating when all of your friends on the group ride are riding Gatorskins. But hey, they are the ones missing out! The heavier riders could have atleast went with GP4000S.... The flat protection and comfort is surprisingly as good as a basic training tire, but still fast enough for serious competition. But if your super light, just get the fastest tires you can and call it a day...

TobinHatesYou
Posts: 1199
Joined: Mon Jul 24, 2017 12:02 pm

by TobinHatesYou

You know what's faster than a 170W effort on Continental Supersonics? A 190W effort on Gatorskins. Why would you use Supersonics to "train?"

Furthermore, a pair of Corsa Speed TLR tires with latex tubes would still be faster than your beloved Supersonics despite the increased weight. Aero > Crr > weight.

eyedrop
Posts: 102
Joined: Wed Jan 27, 2016 5:33 am
Location: Prescott, AZ

by eyedrop

TobinHatesYou wrote:You know what's faster than a 170W effort on Continental Supersonics? A 190W effort on Gatorskins. Why would you use Supersonics to "train?"

Furthermore, a pair of Corsa Speed TLR tires with latex tubes would still be faster than your beloved Supersonics despite the increased weight. Aero > Crr > weight.



You know whats faster than a 190W effort on Gatorskins? 180W on Supersonics... I use Supersonics to train because I can get away with it. I prefer to enjoy riding my bike. Ive tried Gatorskins before. Still got flats, and felt like I was riding solid inner tubes. The performance was horrid. I couldn't wait to get them off my bike...

Furthermore, the Corsa Speed is indeed faster in certain situations, depending on you wheel width and the course your on. It is my second favorite tire. Where I live up in the mountains with steep gradients, the Supersonic with the 50g Supersonic inner tube is preferred...

TobinHatesYou
Posts: 1199
Joined: Mon Jul 24, 2017 12:02 pm

by TobinHatesYou

The point is riding less efficient, less expensive, more durable tires makes sense for training because it's your power output that matters, not your speed. What's a better group training ride, the one where you have to push a little harder or the one where you've equipped everything to make it easier for no reason?

Let's say a latex tube increases the Corsa Speed's Crr from 7.7 to 8.7W. Do you honestly think the 2x(10.2-8.7)=3W difference is going to be made up for by a 90g weight difference on a hill? You have no idea how physics works apparently.

According to Bike-Calculator, a 47kg rider with a 7kg bike at 170W will make it up a 5km and 8% grade climb in 24:34. The same rider +100g +3W makes it up in 24:13. A 21s savings. For someone so keen on optimizing your efficiency, you're doing it wrong.

eyedrop
Posts: 102
Joined: Wed Jan 27, 2016 5:33 am
Location: Prescott, AZ

by eyedrop

TobinHatesYou wrote:The point is riding less efficient, less expensive, more durable tires makes sense for training because it's your power output that matters, not your speed. What's a better group training ride, the one where you have to push a little harder or the one where you've equipped everything to make it easier for no reason?

Let's say a latex tube increases the Corsa Speed's Crr from 7.7 to 8.7W. Do you honestly think the 2x(10.2-8.7)=3W difference is going to be made up for by a 90g weight difference on a hill? You have no idea how physics works apparently.

According to Bike-Calculator, a 47kg rider with a 7kg bike at 170W will make it up a 5km and 8% grade climb in 24:34. The same rider +100g +3W makes it up in 24:13. A 21s savings. For someone so keen on optimizing your efficiency, you're doing it wrong.


All valid points sir. The Supersonics may feel faster than the Corsa Speed, but honestly I have never done a controlled test to compare the two. The Supersonics just seems to accelerate and jump at surges better, which really helps on the super steep sections. They also feel super aggressive and sticky in the corners, and road feel is like a sports car. The Corsa Speed feels more dead and squishy, but rolls over rough surfaces better without bouncing around... But maybe I should re-evaluate...

And I looked back at my post which kind of seemed rude/attacking :oops:

I just feel strongly about my tire choices, thats all. Im the type of guy who pays extra for the best possible performing tires and replace them often, even for my cars. All seasons are crap. I like to buy summer performance tires, and swap out to winter specific tires when needed. I don't care if Im just commuting or racing. Its way worth the extra cost to me as the tires make a massive difference in feel and performance. Same holds true on a bicycle... With the fairly good puncture protection and long life of the GP4000S, why get Gatorskins? They sacrifice EVERYTHING for pure puncture and wear protection. And they are surprisingly expensive locally at retail prices... Sure, they might protect better at things burying their way through the tire, or tiny little stickers might break at the inner liner. But If you get a pinch flat, nasty piece of glass, or nail, your getting a flat no matter what. I noticed its mostly down to luck, and not running over crap...

The only time I suggest Gatorskins is if your riding through a landfill (which is where they belong) :lol: jkjk

TobinHatesYou
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Joined: Mon Jul 24, 2017 12:02 pm

by TobinHatesYou

I only used Gatorskins as an example because it was already mentioned. I'd probably never choose Gatorskins over 4-Seasons for winter riding if we're sticking to Continental choices.

As for tires feeling squishy...this is where perception is taking over reality. A tire with a supple sidewall is faster than a tire with a more rigid one. Vibration, sound, etc. is all lost energy that otherwise would have been moving you forward.

twoangstroms
Posts: 245
Joined: Thu Sep 15, 2005 6:49 am

by twoangstroms

Boy, here in the SF Bay Area the roads can be surprisingly rough and holes can be sharp-edged (not to mention the times I've flatted due to tiny bits of wire). It's also a lot of up and down, and since the force you hit things with is proportional to the square of your velocity (we'll just say speed), items can get driven in when you don't think they would have. We see at least one flat every two weeks on group training rides due to that combo, so no matter how featherweight you are (finally someone smaller than I!), I don't know if delicate tires are ever the way to go here.

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TonyM
Posts: 2161
Joined: Thu Jan 22, 2015 4:11 pm

by TonyM

I used to have dedicated training and race tires as I was racing. Now I don't race anymore and I don't use any "training" tires anymore. But for the winter I choose tires with more grip in the wet (the winter is quite rainy where I now live). I sometimes also adapte the pressure I use depending on the quality of the tarmac and the distance I will bike (i.e. 5 psi less front and rear). And nice advantage of using latex tubes, they loose some pressure after a few hours which makes the long rides more comfortable at the end of the ride.

TobinHatesYou
Posts: 1199
Joined: Mon Jul 24, 2017 12:02 pm

by TobinHatesYou

twoangstroms wrote:Boy, here in the SF Bay Area the roads can be surprisingly rough and holes can be sharp-edged (not to mention the times I've flatted due to tiny bits of wire). It's also a lot of up and down, and since the force you hit things with is proportional to the square of your velocity (we'll just say speed), items can get driven in when you don't think they would have. We see at least one flat every two weeks on group training rides due to that combo, so no matter how featherweight you are (finally someone smaller than I!), I don't know if delicate tires are ever the way to go here.


Yep, especially you ride through the commercial areas in the South Bay a lot. There's just a lot of broken hobo glass, broken taillights, random boxes of nails that fell out of a contractor's truck. It's why I switched to tubeless and never looked back. Even then you're going to miss the occasional huge nail or screw that wont seal. My DynaPlug Racer takes care of everything smaller.

3Pio
Posts: 865
Joined: Wed Mar 09, 2016 7:13 pm

by 3Pio

Update on 4000 SII 23m.. Definetely much faster tire then Vittoria Corsa G+ 25mm. By mig margin.. Also i like how they handle.. The only negative thing compared to Vittoria Corsa G+ 25mm are braking performance.. Seem that braking is better with Vittoria..

JOrange
Posts: 17
Joined: Thu May 25, 2017 10:43 am

by JOrange

~140lb rider here, I train with 25's mostly, (85/100), but also use the same pressures for my 23's. For EZ spin rides and days of leisure, I'll go 60/80.

slowK
Posts: 42
Joined: Wed Apr 23, 2014 5:04 pm

by slowK

59kg, 25mm (nominal) GP 4000s 2 that actually measure 28mm when installed on Boyd Altamonts (19+mm internal width). After lots of experimenting, 55psi front, 70psi rear seems to be my sweet spot. But I just ride for fun.

Marin
Posts: 2754
Joined: Wed Jan 22, 2014 11:48 am
Location: Vienna Austria

by Marin

TobinHatesYou wrote:Why would you use Supersonics to "train?"


Maybe because you like fun / going fast? An effort of X watts will deliver the same training effect no matter on which tires you are, however you might enjoy it more on better tires. I know I do.

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