How soften ride

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07-27-20, 04:27 PM

#26

dsb_mac

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I wonder what your tires actually measure on the wheel. It can be different from the label.

07-27-20, 11:21 PM

#27

cpach

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Quote:

Originally Posted by Drew Eckhardt

While the GP4000 has little sidewall protection, in 28,000 miles riding them I haven't damaged one. Your mileage may vary.

Per https://www.bicyclerollingresistance.com/the-test, test measurements are for one tire on a roller at 18 MPH with a 42.5 kg load

Per https://www.bicyclerollingresistance...-4-season-2015

"Dropping air pressure to 100 psi / 6.9 bars results in a rolling resistance of 18.2 watts (GP4000S = 12.9 watts). At a comfortable air pressure of 80 psi / 5.5 bars, rolling resistance is 19.8 watts (GP4000S II = 13.7 watts)."

That's a net difference of 5.3W @ 100 psi, 6.1W @ 80 psi.

Double that for two tires.

On road rolling resistance on good roads is about 10% higher.

Add 11% increasing speed from 18 to 20 MPH.

12.9 - 14.9 W

It's closer to 15W for a pair than 10W.

Chill, didn't realize we were talking about per pair. I also tend to have pretty good luck with punctures, and as a mechanic I'm pretty fast at fixing flats regardless, but I think that for a lot of riders the evidence is that GP4000s/5000s and similar high performance, everyday tires aren't puncture resistant enough to meet their expectations. My point about the 4 seasons is that they feel obviously and noticeably better than Gatorskins (and are slightly faster) with literally the same puncture protection layers, which is why I try to talk people into those instead of Gatorskins. Also how many of the riders looking at this category are averaging over 20MPH (to be honest, I'm not these days, either

07-28-20, 02:48 PM

#28

The Old Peddler

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Get a Thudbuster seatpost. I am quite impressed with the different makes for your torso. The correct elastomer under your butt really softens those potholes.

The Old Peddler