Crr for the Conti GP TT?...and more...

Jan 22, 17 11:31

Post #1 of 159 (8272 views)

You'll find it here:

http://bikeblather.blogspot.com/...ng-caught-up-ii.html

Summary:

Continental GP TT 23C = .0028, 26W for pair @ 40kph
Continental GP Force 24C = .0030, 27W for pair @ 40kph
Continental SuperSonic 20C = .0030, 28W for pair @ 40kph
Continental GP4000SII 25C = .0031, 28W for pair @ 40kph
Spec. S-Works Turbo TL 26C = .0032, 30W for pair @ 40kph (tubeless)
Continental GP Attack 22C = .0033, 31W for pair @ 40kph
Continental GP4000SII 23C = .0034, 31W for pair @ 40kph
Schwalbe One Tubeless 25C = .0037, 34W for pair @ 40kph
Schwalbe One Tubeless 23C = .0041, 38W for pair @ 40kph
Felt TTR1 23C = .0048, 45W for pair @ 40kph
Continental Gatorskin 25C = .0048, 45W for pair @ 40kph
Continental Gatorskin 23C = .0052, 48W for pair @ 40kph

http://bikeblather.blogspot.com/

Re: Crr for the Conti GP TT?...and more... [Tom A.] [ In reply to ]

Jan 22, 17 11:35

Post #2 of 159 (8262 views)

:)

Re: Crr for the Conti GP TT?...and more... [Tom A.] [ In reply to ]

Jan 22, 17 11:44

Post #3 of 159 (8239 views)

So let's say I'm outfitting a set of Knight 95s as my race wheels, are we saying that the 23C Conti TT is the dominant choice for the setup, or should the 20C Supersonic still be considered due to the much narrower profile, even though they roll ever so slightly worse? Or are the aero gains from 20 vs 23 on the super wide state of the art going to be outweighed by the extra contact patch control?

Re: Crr for the Conti GP TT?...and more... [Tom A.] [ In reply to ]

Jan 22, 17 11:48

Post #4 of 159 (8235 views)

Thank you!

Developing aero, fit and other fun stuff at Red is Faster

Re: Crr for the Conti GP TT?...and more... [Tom A.] [ In reply to ]

Jan 22, 17 11:51

Post #5 of 159 (8223 views)

Great update! Thanks! Looking forward to the Corsa Speed TLR comparison.

One bummer with the Conti line is that there are new versions of the Attack, Force and Supersonic in the pipeline. Along with new tread, the Attack and Force are labeled vIII, but the Supersonic can only be differentiated by new tread and a casing that appears similar to GP TT. This has made it tough when buying sight unseen. I guess this problem will sort itself out quickly as the old stock seems to be nearly exhausted.

Conti appears to be making their tires faster and faster! Though width may end up being an issue. Maybe the Attack III and 2017!SS20 will be the narrow, low Crr options?

Re: Crr for the Conti GP TT?...and more... [Tom A.] [ In reply to ]

Jan 22, 17 13:22

Post #6 of 159 (8126 views)

Thanks Tom, great work!

My Blog - http://leegoocrap.blogspot.com

Re: Crr for the Conti GP TT?...and more... [Tom A.] [ In reply to ]

Jan 22, 17 13:40

Post #7 of 159 (8094 views)

Is the 20mm SS you tested the same as the newer 23 mm version?

If so, I will be holding on to these 23mm tires for dear life.

Re: Crr for the Conti GP TT?...and more... [stevej] [ In reply to ]

Jan 22, 17 13:42

Post #8 of 159 (8082 views)

stevej wrote:

Is the 20mm SS you tested the same as the newer 23 mm version?

If so, I will be holding on to these 23mm tires for dear life.

No, it's perfectly smooth, just like the previous 23c SS

http://bikeblather.blogspot.com/

Re: Crr for the Conti GP TT?...and more... [Tom A.] [ In reply to ]

Jan 22, 17 13:45

Post #9 of 159 (8073 views)

There is some slight disagreement between these stats and brr, yes?

Dan Empfield
aka Slowman

Re: Crr for the Conti GP TT?...and more... [Tom A.] [ In reply to ]

Jan 22, 17 13:46

Post #10 of 159 (8070 views)

Thanks

Do you ever hear from Al Morrison?

Cheers, Neal

+1 mph Faster

Re: Crr for the Conti GP TT?...and more... [Slowman] [ In reply to ]

Jan 22, 17 13:56

Post #11 of 159 (8063 views)

Slowman wrote:

There is some slight disagreement between these stats and brr, yes?

If you mean rank order, I think you keep forgetting he tests clinchers with butyl tubes and I test with latex.

If you mean absolutes, then remember that he uses a diamond-plate roller and doesn't correct for roller size, whereas I use smooth rollers and correct for the roller size (to get flat surface equivalent) and then apply an empirically derived correction to represent "typical" road roughness.

From what I've seen in the past though, our Crr values end up pretty close, and at least the percent differences between tires are consistent between the 2 methods, which is what one would expect.

Any particular ones you think stick out?

http://bikeblather.blogspot.com/

Re: Crr for the Conti GP TT?...and more... [nealhe] [ In reply to ]

Jan 22, 17 13:57

Post #12 of 159 (8059 views)

nealhe wrote:

Thanks

Do you ever hear from Al Morrison?

Occasionally :-)

http://bikeblather.blogspot.com/

Re: Crr for the Conti GP TT?...and more... [Tom A.] [ In reply to ]

Jan 22, 17 14:30

Post #13 of 159 (8026 views)

What psi are these done at? Have you noticed different tires having different rates of change of crr with respect to tire pressure?

------------------------------------------------------------
Any run that doesn't include pooping in someone's front yard is a win.

Re: Crr for the Conti GP TT?...and more... [CCF] [ In reply to ]

Jan 22, 17 14:39

Post #14 of 159 (8018 views)

CCF wrote:

What psi are these done at? Have you noticed different tires having different rates of change of crr with respect to tire pressure?

Unless otherwise noted in the spreadsheet linked to on the blog, they are all done at 120psi. That's done to be consistent with the original test data set. For some of the wider tires, I've started testing them on a 21mm internal width rim at 100psi, since it was getting sketchy/dangerous pumping wide tires up to 120 on the Mavic Open pro at only 15mm width. I've found the Crr measurement to be the same for both setups on a given tire.

I have not done much Crr vs pressure testing...it's time consuming enough as it is ;-)

The BRR data should give you an idea of how various tires react to pressure differences, at least in a percentage basis.

http://bikeblather.blogspot.com/

Last edited by: Tom A.: Jan 22, 17 18:04

Re: Crr for the Conti GP TT?...and more... [Tom A.] [ In reply to ]

Jan 22, 17 14:54

Post #15 of 159 (7985 views)

So if one wants to have the best setup for race day, and one plans to switch out a training tire for a "faster" race tire, how long before (how many mikes/km) a race should this be done? I'm assuming there's a break-in period.

Re: Crr for the Conti GP TT?...and more... [jeremyebrock] [ In reply to ]

Jan 22, 17 14:59

Post #16 of 159 (7972 views)

jeremyebrock wrote:

So if one wants to have the best setup for race day, and one plans to switch out a training tire for a "faster" race tire, how long before (how many mikes/km) a race should this be done? I'm assuming there's a break-in period.

Well...then you get into trying to trade off improved Crr vs. worsened aerodynamics (due to casing "growth" and tread wear).

I wouldn't stress about it ;-)

http://bikeblather.blogspot.com/

Last edited by: Tom A.: Jan 22, 17 15:00

Re: Crr for the Conti GP TT?...and more... [Tom A.] [ In reply to ]

Jan 22, 17 15:55

Post #17 of 159 (7924 views)

Haha ok :)

Re: Crr for the Conti GP TT?...and more... [Tom A.] [ In reply to ]

Jan 22, 17 16:57

Post #18 of 159 (7853 views)

Tom A. wrote:

You'll find it here:

http://bikeblather.blogspot.com/...ng-caught-up-ii.html

Summary:

Continental GP TT 23C = .0028, 26W for pair @ 40kph
Continental GP Force 24C = .0030, 27W for pair @ 40kph
Continental SuperSonic 20C = .0030, 28W for pair @ 40kph
Continental GP4000SII 25C = .0031, 28W for pair @ 40kph
Spec. S-Works Turbo TL 26C = .0032, 30W for pair @ 40kph (tubeless)
Continental GP Attack 22C = .0033, 31W for pair @ 40kph
Continental GP4000SII 23C = .0034, 31W for pair @ 40kph
Schwalbe One Tubeless 25C = .0037, 34W for pair @ 40kph
Schwalbe One Tubeless 23C = .0041, 38W for pair @ 40kph
Felt TTR1 23C = .0048, 45W for pair @ 40kph
Continental Gatorskin 25C = .0048, 45W for pair @ 40kph
Continental Gatorskin 23C = .0052, 48W for pair @ 40kph

What are your thoughts on the GP TT on a Mavic CXR 60 with the blades installed?

Re: Crr for the Conti GP TT?...and more... [GreenPlease] [ In reply to ]

Jan 22, 17 17:09

Post #19 of 159 (7839 views)

GreenPlease wrote:

Tom A. wrote:

You'll find it here:

http://bikeblather.blogspot.com/...ng-caught-up-ii.html

Summary:

Continental GP TT 23C = .0028, 26W for pair @ 40kph
Continental GP Force 24C = .0030, 27W for pair @ 40kph
Continental SuperSonic 20C = .0030, 28W for pair @ 40kph
Continental GP4000SII 25C = .0031, 28W for pair @ 40kph
Spec. S-Works Turbo TL 26C = .0032, 30W for pair @ 40kph (tubeless)
Continental GP Attack 22C = .0033, 31W for pair @ 40kph
Continental GP4000SII 23C = .0034, 31W for pair @ 40kph
Schwalbe One Tubeless 25C = .0037, 34W for pair @ 40kph
Schwalbe One Tubeless 23C = .0041, 38W for pair @ 40kph
Felt TTR1 23C = .0048, 45W for pair @ 40kph
Continental Gatorskin 25C = .0048, 45W for pair @ 40kph
Continental Gatorskin 23C = .0052, 48W for pair @ 40kph

What are your thoughts on the GP TT on a Mavic CXR 60 with the blades installed?

Could be good...the extra narrow internal width of that rim should help "tame" the oversize nature of that tire when mounted.

http://bikeblather.blogspot.com/

Re: Crr for the Conti GP TT?...and more... [GreenPlease] [ In reply to ]

Jan 22, 17 17:10

Post #20 of 159 (7839 views)

I've just switched to Gatorskins for my road bike which coincided with a month off cycling and have really struggled. I put it down to lack of cycling fitness, but perhaps the Gatorskins are a significant contributor??

Re: Crr for the Conti GP TT?...and more... [zedzded] [ In reply to ]

Jan 22, 17 17:11

Post #21 of 159 (7838 views)

zedzded wrote:

I've just switched to Gatorskins for my road bike which coincided with a month off cycling and have really struggled. I put it down to lack of cycling fitness, but perhaps the Gatorskins are a significant contributor??

I don't think "perhaps" is the right word ;-)

http://bikeblather.blogspot.com/

Re: Crr for the Conti GP TT?...and more... [Tom A.] [ In reply to ]

Jan 22, 17 17:23

Post #22 of 159 (7818 views)

Will the old Continental Supersonic 23C or the Continental GP TT 25C be tested?

Timothy Winslow

Re: Crr for the Conti GP TT?...and more... [timmywins] [ In reply to ]

Jan 22, 17 17:38

Post #23 of 159 (7798 views)

He's already tested the GP SS 23c, see his spreadsheet.

The only GP TT I've seen is a 23c that mounts up like a 25c+. Have you seen something about a GP TT 25c?

Re: Crr for the Conti GP TT?...and more... [SummitAK] [ In reply to ]

Jan 22, 17 17:51

Post #24 of 159 (7775 views)

This is awesome. Thank you.

Do repeat tests suggest a margin of error (or lack thereof) for your tests?

Re: Crr for the Conti GP TT?...and more... [HLS2k6] [ In reply to ]

Jan 22, 17 18:03

Post #25 of 159 (7759 views)

HLS2k6 wrote:

This is awesome. Thank you.

Do repeat tests suggest a margin of error (or lack thereof) for your tests?

I consider any tire within .0001 Crr of another using this methodology to be basically "tied" (within the error of the measurement). That works out to be within ~1W for a pair of tires at 40 kph.

When I first started, I did multiple repeats to on the same tire (23c Conti GP4k) for this purpose and quickly realized there's an ambient temperature dependence that's fairly significant. That led to my temperature correction and is why the results are all normalized to 20C.

http://bikeblather.blogspot.com/

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