Go Back  Bike Forums > Bike Forums > Cyclocross and Gravelbiking (Recreational)
Reload this Page >

Rolling resistance of Gravel Tires! Is your tire "fast?" bicyclerollingresistance

Notices
Cyclocross and Gravelbiking (Recreational) This has to be the most physically intense sport ever invented. It's high speed bicycle racing on a short off road course or riding the off pavement rides on gravel like : "Unbound Gravel". We also have a dedicated Racing forum for the Cyclocross Hard Core Racers.

Rolling resistance of Gravel Tires! Is your tire "fast?" bicyclerollingresistance

Old 07-06-20, 10:06 AM
  #1  
chas58
Senior Member
Thread Starter
 
chas58's Avatar
 
Join Date: Jul 2010
Location: Michigan
Posts: 4,863

Bikes: too many of all kinds

Mentioned: 35 Post(s)
Tagged: 0 Thread(s)
Quoted: 1147 Post(s)
Liked 415 Times in 335 Posts
Rolling resistance of Gravel Tires! Is your tire "fast?" bicyclerollingresistance

I've been waiting for this for years. Now we can see how some of our favorite gravel & CX tires stack up with road and mountain bike tires. Obviously there are a lot of factors besides rolling resistance to make up a fast tire, but this is a good data point for decision making.

https://www.bicyclerollingresistance...gravel-reviews

Seems to match up well with the TOUR tire test, with most tires being about 25-27watts rolling resistance, with Conti Terraspeed and Gravel King Slicks being noticeably faster.
I'm looking forward to seeing this list grow.

For reference - here is the TOUR test: https://www.roadbike.de/rennrad-part...eifen-im-test/

And the Grand Fondo test: https://granfondo-cycling.com/the-best-gravel-tire/
chas58 is offline  
Likes For chas58:
Old 07-06-20, 01:38 PM
  #2  
chas58
Senior Member
Thread Starter
 
chas58's Avatar
 
Join Date: Jul 2010
Location: Michigan
Posts: 4,863

Bikes: too many of all kinds

Mentioned: 35 Post(s)
Tagged: 0 Thread(s)
Quoted: 1147 Post(s)
Liked 415 Times in 335 Posts
The Dutch Test (Bicycle Rolling Resistance)


TOUR - The German Test (Rolling resistance @ 50psi, tubed, 30km/hr)


The Grand Fondo test (DE/UK?)


Last edited by chas58; 07-09-20 at 08:51 AM.
chas58 is offline  
Old 07-08-20, 02:16 PM
  #3  
shoota 
Senior Member
 
shoota's Avatar
 
Join Date: Jun 2012
Location: Stillwater, OK
Posts: 8,128
Mentioned: 33 Post(s)
Tagged: 0 Thread(s)
Quoted: 1871 Post(s)
Liked 689 Times in 467 Posts
What does the Puncture Test (Tread/Sidewall points) mean?
__________________
2014 Cannondale SuperSix EVO 2
2019 Salsa Warbird
shoota is online now  
Old 07-09-20, 08:09 AM
  #4  
mstateglfr 
Sunshine
 
mstateglfr's Avatar
 
Join Date: Aug 2014
Location: Des Moines, IA
Posts: 16,532

Bikes: '18 class built steel roadbike, '19 Fairlight Secan, '88 Schwinn Premis , Black Mountain Cycles Monstercross V4, '89 Novara Trionfo

Mentioned: 123 Post(s)
Tagged: 0 Thread(s)
Quoted: 10897 Post(s)
Liked 7,384 Times in 4,144 Posts
Interesting that the 4 gravel tire tests I just looked at on BRR all measured narrower than the stated width.
The info is neat and all, but I think it really misses on the market, which is tires on the wider end of what they will test and some even wider than that.

The category is cx/gravel tires, but limiting testing to 32-40mm tires and having many(most?) at 37mm or smaller is missing out on a lot of the market.
Tires that are 37-45mm wide is where the gravel market has moved to with so many frames at all price levels being able to handle wider and wider tires each year.

Oh well, it isnt my work and very few others are doing it, so beggars and choosers kinda applies here. But the site does exist to get views and clicks- I just think tires that are more all around gravel oriented would be beneficial.
mstateglfr is online now  
Likes For mstateglfr:
Old 07-09-20, 01:56 PM
  #5  
chas58
Senior Member
Thread Starter
 
chas58's Avatar
 
Join Date: Jul 2010
Location: Michigan
Posts: 4,863

Bikes: too many of all kinds

Mentioned: 35 Post(s)
Tagged: 0 Thread(s)
Quoted: 1147 Post(s)
Liked 415 Times in 335 Posts
Originally Posted by shoota
What does the Puncture Test (Tread/Sidewall points) mean?
how easy the sidewall and the tread are to puncture. ;-)
(using 1mm steel needle)
chas58 is offline  
Old 04-28-21, 10:12 AM
  #6  
jfranci3
Full Member
 
Join Date: Apr 2009
Posts: 272
Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 120 Post(s)
Liked 44 Times in 38 Posts
Originally Posted by mstateglfr
Interesting that the 4 gravel tire tests I just looked at on BRR all measured narrower than the stated width.
The info is neat and all, but I think it really misses on the market, which is tires on the wider end of what they will test and some even wider than that.

The category is cx/gravel tires, but limiting testing to 32-40mm tires and having many(most?) at 37mm or smaller is missing out on a lot of the market.
Tires that are 37-45mm wide is where the gravel market has moved to with so many frames at all price levels being able to handle wider and wider tires each year.

Oh well, it isnt my work and very few others are doing it, so beggars and choosers kinda applies here. But the site does exist to get views and clicks- I just think tires that are more all around gravel oriented would be beneficial.
They use a narrow rim. The tire sizes are an estimated installed size for the rim they think you'll use. For every mm wider, you get an installed width about .25mm larger. They're using a 17mm internal rim, and most folks would use a 22mm+ now. They also need to spec based on max PSI, BRR tests at regular pressures. Finally, sometimes they call it a "40c" an the ETRTO is 38-622 (Continental).
jfranci3 is offline  
Old 04-29-21, 11:52 AM
  #7  
jonathanf2
Senior Member
 
Join Date: Dec 2020
Location: Los Angeles
Posts: 902
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 439 Post(s)
Liked 999 Times in 428 Posts
I was really surprised the Pasela PT tires at 38c actually had less rolling resistance than the GravelKing TLC, since I was debating between these two tires for my 2nd wheelset (posted a thread about which to choose). The TLC tires seem to be a tad wider in actual use, could that account for the discrepancy?

jonathanf2 is offline  
Old 04-29-21, 12:15 PM
  #8  
HTupolev
Senior Member
 
Join Date: Apr 2015
Location: Seattle
Posts: 4,261
Mentioned: 41 Post(s)
Tagged: 0 Thread(s)
Quoted: 1971 Post(s)
Liked 1,297 Times in 629 Posts
Originally Posted by jonathanf2
The TLC tires seem to be a tad wider in actual use, could that account for the discrepancy?
No. At like-for-like pressure, a wider tire will have lower crr on the drum. If anything, that makes the Pasela look better.
HTupolev is offline  
Old 04-29-21, 12:25 PM
  #9  
zandoval 
Senior Member
 
zandoval's Avatar
 
Join Date: May 2010
Location: Bastrop Texas
Posts: 4,416

Bikes: Univega, Peu P6, Peu PR-10, Ted Williams, Peu UO-8, Peu UO-18 Mixte, Peu Dolomites

Mentioned: 13 Post(s)
Tagged: 0 Thread(s)
Quoted: 928 Post(s)
Liked 1,594 Times in 1,020 Posts
I really don't have a gravel bike per-say but it looks like I have transitioned into one with all the changes I have had to make in riding on my country roads. I have been through many brands of cheap tires and have found the best tire for my rides. The tire is not on your list but should be considered. The center ridge offers little resistance on pavement and there is just enough grip on the sides to help in soft terrain. About 30.00 USD...

Continental Tour Ride Urban

https://images-na.ssl-images-amazon....AC_SL1000_.jpg
__________________
No matter where you're at... There you are... Δf:=f(1/2)-f(-1/2)
zandoval is offline  
Old 04-29-21, 04:41 PM
  #10  
dwmckee
Senior Member
 
dwmckee's Avatar
 
Join Date: Jun 2008
Location: Pittsburgh, PA
Posts: 2,468

Bikes: Co-Motion Cappuccino Tandem,'88 Bob Jackson Touring, Co-Motion Cascadia Touring, Open U.P., Ritchie Titanium Breakaway, Frances Cycles SmallHaul cargo bike. Those are the permanent ones; others wander in and out of the stable occasionally as well.

Mentioned: 7 Post(s)
Tagged: 0 Thread(s)
Quoted: 427 Post(s)
Likes: 0
Liked 339 Times in 229 Posts
Originally Posted by mstateglfr
Interesting that the 4 gravel tire tests I just looked at on BRR all measured narrower than the stated width.
The info is neat and all, but I think it really misses on the market, which is tires on the wider end of what they will test and some even wider than that.

The category is cx/gravel tires, but limiting testing to 32-40mm tires and having many(most?) at 37mm or smaller is missing out on a lot of the market.
Tires that are 37-45mm wide is where the gravel market has moved to with so many frames at all price levels being able to handle wider and wider tires each year.

Oh well, it isnt my work and very few others are doing it, so beggars and choosers kinda applies here. But the site does exist to get views and clicks- I just think tires that are more all around gravel oriented would be beneficial.
BRR comes out of road riding in the early days and they were slow to buy into wide for gravel, hence the slow creep-up to wider tires in their ratings. I remember their first 35mm rating and they thought that was really wide at the time when we were all riding 38-42 mm.

It is common for manufacturers to have tires that measure narrower than their rated size. They do this to offer a lighter tire at an advertised width. But we are all smarter than that.
dwmckee is offline  
Old 05-02-21, 07:57 PM
  #11  
scottfsmith
I like bike
 
scottfsmith's Avatar
 
Join Date: Feb 2021
Location: Merry Land USA
Posts: 662

Bikes: Roubaix Comp 2020

Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 267 Post(s)
Liked 283 Times in 191 Posts
Originally Posted by jonathanf2
I was really surprised the Pasela PT tires at 38c actually had less rolling resistance than the GravelKing TLC, since I was debating between these two tires for my 2nd wheelset (posted a thread about which to choose). The TLC tires seem to be a tad wider in actual use, could that account for the discrepancy?
Unfortunately when you are comparing touring and gravel tires you can get misled from how data are presented on that site.

The TLC's "20.8" number is at what they call low air pressure which for the measured width of that tire (36.5mm) is 36psi. The Pasela PT's "20.6" number is at 60psi and it measures 35.2mm wide. So, you can't really compare these numbers. These tires are not far off in width but they consider the sweet spot for a touring tire to be at higher pressure due to road use, whereas gravel tires need to handle bumps so they are using lower pressures.

The Pasela at 45psi is 23.6 watts which shows it is inferior for rolling resistance compared to the TLC: more psi but more watts compared to the 20.8 watts at 36psi on the TLC's. The TLC on the road would be run at a slightly lower pressure than the Pasela due to the 36.5 vs 35.2mm width, but that is only 1.3mm difference in width which will be minor psi difference, so the TLC should be a better tire overall for rolling resistance.

I wish they would just use absolute psi values for the gravel tires, it gets confusing trying to understand the data they way they do it now.
scottfsmith is offline  
Likes For scottfsmith:
Old 05-02-21, 10:59 PM
  #12  
sincos
Full Member
 
Join Date: Nov 2020
Posts: 245
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 98 Post(s)
Liked 127 Times in 74 Posts
Originally Posted by scottfsmith
Unfortunately when you are comparing touring and gravel tires you can get misled from how data are presented on that site.

The TLC's "20.8" number is at what they call low air pressure which for the measured width of that tire (36.5mm) is 36psi. The Pasela PT's "20.6" number is at 60psi and it measures 35.2mm wide. So, you can't really compare these numbers. These tires are not far off in width but they consider the sweet spot for a touring tire to be at higher pressure due to road use, whereas gravel tires need to handle bumps so they are using lower pressures.<...>
I wish they would just use absolute psi values for the gravel tires, it gets confusing trying to understand the data they way they do it now.
Just to add to that the difference between 20.8 and 20.6 is not quite 1%. They don't specify but I'd call that well within MOE. And while I'm at it, being a certified dork and all, the plural of anecdote isn't data. Given the paucity of other measurements, BRR provides a valuable data point, but that's all it is, a data point. Furthermore, it's from a rolling drum. Different real world surfaces with different impedances will likely give different results, quite possibly even different relative results.

Not to be harsh on BRR -- they cannot possibly account for everything, they do a good job with what they can do, and they do provide useful information. But as with everything else, mind the precision, and don't take the numbers too seriously.
sincos is offline  

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off


Thread Tools
Search this Thread

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service -

Copyright © 2024 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.