Loving 80 psi

[sjbraun]

I was able squeeze in a ride before work this morning. Usually I inflate my tires to 90-100 psi, but this morning, I just gave 'em a pinch, pronounced them adequately inflated and took off. My Hampstem seemed to ride especially smoothly over Tucson's rutted and cracked roadways. So out of curiousity, I checked the tire pressure when I returned from my ride, 80 psi, front and back. I'm running 25mm Michelin Pro4 Endurance tires, which actually measure closer to 28mm on Velocity A23 rims. At 175#, the ride was plush and I never worried about pinch flats.

If you haven't tried running wider tires and lower pressure yet, my experience today suggests you might want to give it a try.

Steve

[notoriousdjw]

I started checking my tires before each ride with a digital tire gauge and brass presta-to-schrader adapter and I found something similar. It only takes 10 psi to go from a springy pneumatic ride to one that rattles the shifters over every bump. For me the magic numbers are about 90r/80f on 23c tires Schwalbe Ones and 70r/65f on 28c Hutch sectors. I'm 175lbs riding on the carpet-bombed streets of Seattle.

[farmersam]

Thanks for confirming. I posted sometime ago about the bumpy roads in my area jarring me on my cross. It was recommended to deflate from 60/65 to 35/40 on a cross.

[eddief]

but great you discovered lower pressure. People I ride with are religious about inflating to a 100; even women at less than 150 lbs. You can tell em and tell em and tell em, but religion gets in their way. Me 190ish, Michelin Lithion x 25mm, at 80 psi. Just works.

[marciero]

I was bombing down long dirt descents in the Green Mts last week comfortably with 28 tires at 70/75. For me that seems to be enough to avoid pinch flats, and they still handle fairly responsively on the pavement.

[notoriousdjw]

I would share this chart (http://www.bicyclerollingresistance.com/road-bike-reviews) and show them that most tires have <1w difference between 80 and 100 and ~2w difference between 80 and 120. That's a lot of pain to endure for 2 watts!

[MattTuck]

That chart is great. thanks for posting.

[guido]

I would share this chart (http://www.bicyclerollingresistance.com/road-bike-reviews) and show them that most tires have <1w difference between 80 and 100 and ~2w difference between 80 and 120. That's a lot of pain to endure for 2 watts!

Wow they actually found a tire with more rolling resistance than a Gatorskin. I thought it could never be done...

[marciero]

Yes, great chart, especially for comparison of various tires. Should keep in mind though that rolling resistance does not tell the whole story - on rough surfaces a high pressure tire will ride more slowly, or so the evidence seems to suggest. I am assuming the data in the chart was generated using some type of smooth drum/dynamometer setup.

[brownhound]

Jeez, maybe I have bad luck but I've gotten three pinch flats this year trying low PSI. Two on 23mm (Michelin Pro4) running around 80-90 and one on a 35mm (Clement USH) running around 50-60.

I keep my tires pumped high now, and consider the low PSI experiment over. For the record, I'm 155lbs. The flats seemed mostly to be from gravel.

[notoriousdjw]

Yes, great chart, especially for comparison of various tires. Should keep in mind though that rolling resistance does not tell the whole story - on rough surfaces a high pressure tire will ride more slowly, or so the evidence seems to suggest. I am assuming the data in the chart was generated using some type of smooth drum/dynamometer setup.

If you read the section of that site called "the test (http://www.bicyclerollingresistance.com/the-test)" it expains:

the drum is covered with diamond plate to simulate an average road surface. This comes a lot closer to a real road surface than the usual very smooth steel drum.

[tumbler]

Nice charts. According to this, I can blame all of my slowness on my Conti 4Seasons. Apparently I need some Grand Prix 4000S II's from 2014 with latex tubes.

[Steve in SLO]

Latex versus non-latex tubes is a real eye-opener, IMHO.

[Llewellyn]

I've been riding 75-80F/70-65R for a while now. What a difference - I can't believe it took me so long

[etu]

Below 60 - feels sluggish, except for off road, mixed terrain
60-80 nice balance for fast commutes and long weekend social rides
80-100 aggressive weekend rides with friends

[Ken Robb]

Latex versus non-latex tubes is a real eye-opener, IMHO.

Maybe I missed something but I didn't see any tests with latex vs. other tubes in the same tire. That would be interesting but as it is, we can't tell if the two low resistance results are due to the latex tubes or the tires.

[notoriousdjw]

Maybe I missed something but I didn't see any tests with latex vs. other tubes in the same tire. That would be interesting but as it is, we can't tell if the two low resistance results are due to the latex tubes or the tires.

Click here (http://www.bicyclerollingresistance.com/specials/schwalbe-one-tubeless-clincher) for just such a comparison.

[Steve in SLO]

Maybe I missed something but I didn't see any tests with latex vs. other tubes in the same tire. That would be interesting but as it is, we can't tell if the two low resistance results are due to the latex tubes or the tires.

Ken,
Look on the table at:
Lines 1 and 5 GP4000S. Ii latex versus non-
Lines 3 and 8 - Vittoria Open Corsa CX III latex vs non-

[etu]

Weren't there conflicting data from BQ roll down tests?

[Russian bear]

Running Open Paves 27mm. Running 85/80 r/f here on our Tucson roads.

[joe.e]

I ride pretty nasty roads in L.A, and usually run my tires around 90, but given my weight, and the responses in this thread, I think I'm gonna knock it down a couple pounds and see how I like it.

Realizing that you don't HAVE to run your tires at 100 all the time was one of my first real "A-HA" cycling moments.

[Scuzzer]

I keep my tires pumped high now, and consider the low PSI experiment over. For the record, I'm 155lbs. The flats seemed mostly to be from gravel.

I ride 32s on gravel at 65psi rear and 55psi front. I"m huge by cycling standards (6'2" and 220lbs) and ride in the high rockies where I'm going uphill 80% of the time but the other 20 is bombing downhills like this with huge rocks everywhere:

http://i230.photobucket.com/albums/ee168/lamamandemma/120112cabina.jpg (http://s230.photobucket.com/user/lamamandemma/media/120112cabina.jpg.html)

I also ride 25s on the road at 90 and 28s at 85, haven't noticed a speed or flat penalty.

Not saying you're wrong of course, but some of us have a totally different experience running lower pressures.

[Ken Robb]

Ken,
Look on the table at:
Lines 1 and 5 GP4000S. Ii latex versus non-
Lines 3 and 8 - Vittoria Open Corsa CX III latex vs non-

Yep, that's what I missed. Thanks

[aosty]

I just rode down the coast of CA... tubeless 28mm @ 70psi worked great!

http://images.tapatalk-cdn.com/15/07/29/6ee83d98cbafa52b715cfa4ccc14f9ce.jpg

[Tony]

Toured light! Did you have support alone the way?

[aosty]

Toured light! Did you have support alone the way?

Credit card touring! :banana:

[rpm]

This season at 185 lbs I've been running Michelin Pro 4 Service Course 25's at 85 psi in the rear and 80 in the front. Really smooth and puncture free. I used to run Conti 4000's at 95 in the rear and 90 in the front. Definitely a smoother ride with less pressure in the Pro 4's.