Trsnrtr

All I know is that riding roads in the winter covered with grit, I need all of the protection that I can get from tubeless to keep from changing flats in 25-30ºF weather. I run 25mm at 5.5 bar and I weigh 200#. I get a silky, smooth ride and a little peace of mind so tubeless is totally worth it to me.

phrantic09

This x 10.

I’m running 28mm GP 5000 tubeless at 60 PSI. The ride is sublime, the traction excellent and flats are much less of a concern on dirty debris filled winter roads.

AdkMtnMonster

Same tires, roughly the same pressure as you stated. One pinch flat on my rear tire in all of 2020, and it was due to a pothole that I hit @ 52+mph (I had been at 57mph just before I hit it!). That will get your attention. It was a minor inconvenience to swap out the tube and puff up the new one to be on my way again. I don’t mind tubes compared to the messiness of tubeless, especially on the road. Mountain bikes are a whole ‘nether story.

Psimet2001 

I have customers who love tubeless on the road. I have customers who hate it. As many here already know I am generally not a fan of tubeless but at this point there's no point in me taking a contrary position to it.

For myself -
Road: Tubed
Road Racing: Tubular
Gravel: Tubeless
Cross: Tubular
Mtb: Tubeless (who am I kidding I don't mtb)
Fatbike: Tubeless (same as mtb)
Track: Tubular (easy choice here as a good set of glued tires can last eons on the track. I just peeled some Atlanta Olympics tires off a set last year - he wanted them reglued again I suggested a replacement)

As for tubeless being an earth shattering improvement on the road....yeah/no. If you're someone who has always been plagued with flats then sure...go for it. If you're an enthusiast that hardly gets flats anyway then no you won't really see any sort of truly appreciable difference.

All of this is moot anyway though. Just like disc brakes it's just an industry mandate that tubeless is god (for tech).

cxwrench

^All of this^...exactly.

Redbullet

Yes, but... I am now riding with the fastest tires on my bike. Capisci?

Grouperdawg

I weigh 200lbs and went from 25 conti 5,000s to conti tubeless 25 5,000s and the ride comfort was significant. I then went to 28s tubeless and it is like riding on a cloud and I will never go back. I think the 28s are faster on the roads I ride. They definitely aren’t slower and I can ride 50-100 miles without the back pain i used to have and that alone probably makes me faster, I run 80 psi in the back and 75 in the front.

Branko D

For me, the biggest issue with tubed GP5000s was that replacing them was a big chore on my tubeless ready wheelsets (on the other hand, on the one non-tubeless wheelset we have in house it's trivial to replace the tube). Coupled with using latex tubes, which do feel better to ride on, having to wrangle the tire back on with levers the tube would sometimes migrate and get pinched by the bead of the tire. Never had an actual pinch flat and regular flats were reasonably rare, though. Replacing them with Vittoria tubeless, after a couple of rides and about 100 miles, I can't say that it feels like a big difference to GP5000s with latex - they both feel pretty damn awesome - but at least they are way easier to put on than GP5000s, and tests say they do roll slightly faster. I'll see how I get on with them, but initial impressions are good even though it's not a big difference. My wife used them on her TT bike without issues for a bit over half a year, too.

Roads around here are good enough and I'm light enough that running lower pressures was never a factor for me, but it might be a factor for some. Tubeless isn't a gamechanger from my point of view, but is incremental progress.

DrIsotope

The OP isn't feeling any difference because he's running his new tubeless tires at far too high of a pressure. I'm closer to 100kg, and ran my 700x23 IRC Roadlites @ 90psi. With 25s it's low 80s. Anything wider is generally minimum recommended on the sidewall.

At the same time, I don't understand the change either. I get around two tire-related "incidents" a year with tubeless. On tubes, I would get a flat every 5-7 rides. If I could be guaranteed to go 10k miles without a flat, I'd be back on tubes within the hour.

Branko D

You can run such low pressures on tubed tires, too (at least I can with my 70-ish kg) but outside of truly dismal quality backroads it's just not ideal.

Possibly I'm spoiled by generally functioning road maintenance services which do a reasonable job on main roads, but most of the time I stick with 105-115 psi depending on road and conditions and only do 90-95 psi when I'm going to train on some backroad climbs around me.

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cxwrench

You'd have to be on a wood velodrome for your favored tire pressure(s) to actually be faster. On a concrete track I never went over 100 and preferred the better ride and increased traction of somewhat lower pressure. At 115 I promise you're bouncing around more than you should be and your cornering traction is compromised. Physics are physics. What size tires just so I know?

Branko D

23mm in front, 25mm in rear. Since there's more weight over the rear, especially when climbing, I tend to use the same pressure in both. Running 90 psi was only faster for me on some of the worst local roads around (looking at power vs speed on local climbs). I tried doing a local uphill race with 90 psi, but especially on steeper bits where most of weight is on the rear, it just felt all sorts of wrong, and I went slightly slower over those than I did in training.

115 is what I go with on the our best roads; I knock it down to 110-105 on the slightly worse ones, but only go below that on the really crappy roads. From what I've seen, these are actually optimal pressures for speed.

WhyFi

If this is correct, and I have serious doubts that it is, you need to change your location to: The Land of Glassy-smooth Roads.

cxwrench

Uhmmm, no.

gregf83 

How are you determining optimum tire pressure?

cxwrench

Depends on rider weight, tire size, rim width. Also depends on riding/road condition. I weigh about 160. For a 23mm road tire on a normal 17-19mm rim I'd go about 95rr/85frt. For every tire size bigger I'd drop roughly 10psi. No one needs more than 100psi on the road...if they truly do they really need bigger tires not more pressure. If you can't use bigger tires on your bike when you truly need them you bought the wrong bike. Simple.

gregf83 

I'm just curious how you are so confident that the pressures mentioned above are wrong. It takes some fairly careful measurements to detect differences of 5-10 psi.

cxwrench

Others that are much more intelligent than I have tested. Higher pressures (over 100psi in 23-25mm tires) has been proven time and again to be slightly slower than lower pressure. The harder the tire the lower the mechanical grip, so less traction. Ride quality? The answer is obvious. To be honest the differences in rolling resistance are very minor compared to the gains in comfort and traction. If you're feeling every little bit of pavement texture and every small bump in the road it might feel fast but in reality if you're feeling these things it's because the bike is bouncing off of them...and if that's happening you're experiencing higher levels of rolling resistance. The tire is the only suspension on a road bike...let it do it's work. You'd have to drop down to very low pressure before you'd start losing energy to tire flex (hysteresis). For most people this would be lower than the pressure at which the tire started to feel too 'mushy' or flexible.

cycle17

My wife and I both bought new bikes with Tubeless + Disc wheelsets in 2020. She is running 28c Michelin Power Road TLRs on her Avail and I'm running 28c Giant Gavia Course tires on my TCR. Together we both rode a combined 7000+ miles with zero flats or issues.

But here's the thing... She's 122lbs and runs 58-60psi in her tires with zero issues. She describes it like cycling on shock absorbers compared to her old road bike with 25c tubed at 95-100psi. I'm 195lbs and running my tires around 88 psi versus the 105-110 I ran with tubed clinchers. These pressures are also based on our rim widths. To say the the handling and ride comfort is far better is a huge understatement!

While I can only speak to our own experiences, tubeless road setup (and Disc Brakes) are certainly two things that have made our riding more enjoyable.

surak

Tires are faster underinflated than over because the power loss ramps up much more quickly beyond the ideal pressure (which is hard to predict).



Chart from Silca blog

Branko D

Sounds like tire pressure is best matched against known tire size and (typically) known road quality, and erring downward is preferable to erring upward. Still, it doesn't support running sub 100 psi pressures on narrow 25 and 23mm tires.

Personally, I tried GP5000s (which do run narrower than 4000SIIs, effectively pushing the entire graph to the right) at all sorts of pressures ranging from 85 psi to 115 psi (and a few times even less, after patching a flat or such), and optimal pressures on good roads are clearly not 90 psi on narrow tires.

There's also the unknown factor of how accurate is your or my pump manometer. One of these days I'll probably buy those overpriced gauges which thread in the valve and give supposedly accurate pressure readings on the fly. Given the variability of pumps my 110 psi could be something like your 103 psi and that would make for a marked difference.

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gregf83 

If you're running 23mm tires it's a tradeoff between ride quality and possibility of a pinch flat. For me, pinches are more likely to happen when riding in a group when visibility, and ability to avoid obstacles is diminished. It just takes one small rock to cause a pinch and I've had a reasonable number of them over the years. I'd rather have a slightly harsher ride and minimize the possibility of a pinch although I'm also lazy and don't pump my tires before every ride so I would usually pump 23s initially to 110 and then use the finger test to determine when to add more air.

Whether pressures above 100psi result in slower speed is entirely dependent on the surface. Our local crits are run in industrial parks on decent pavement and I think it would be tough to say for certainty what the optimum pressure is without testing.

For most of the last year this is moot to me as I haven't been doing any group rides and I've been riding on cushy 28mm tubeless tires. I start at 70 and can go over a month before reinflating.

surak

Don't assume those PSIs on the chart mean anything other than in whatever test protocol they used. In fact, it's easy to get a lower pressure recommendation from the data-backed Silca tire pressure calculator.

Redbullet

I think there are 2 paradigms that are to easily accepted by the vast majority:

1. "Risk of pinch flats": I think that in real life, a 85 kg (or less) guy riding 23 mm road tires, inflated at 90 PSI, does not encounter a pinch, unless he takes such a hard hit, that makes him crash and seriously damage the wheel and maybe other parts of the bike. In such circumstances, the pinch is totally irrelevant compared to the crash and the other damages. So, most road riders can ride "pinch safe" with 23 mm tube tires at 90 PSI.

2. "Wider tire is always faster": That depends. Deeper research shows that gains that may come from using 25 (or 28)mm tires instead of 23mm can easily be offset and even overcame by loses due to air drag, if wider tires are mounted on shallow rims (i.e.: if tire profile is larger than rim profile and the system does not show a continuous shape). So, I doubt that, overall, 25 mm tires would be faster on my shallow rims, than 23 mm (and, by the way, in real life, 25mm tires measure some 26-27 and 23mm tire measure 24-25).

WhyFi

I haven't parsed all of the replies, but I'd be surprised to see anyone speaking in absolutes like, "wider is always faster."

I think that most people that have embraced wider tires realize that there are potential trade-offs, they're faster under certain conditions and that those conditions aren't terribly usual for many of us. For my less than pristine roads and often quite lengthy rides, I have no doubt that I'm better served by my 28s at ~60psi than I would be by 23s at 90+

And, by the way, in real life, tire measurements vary. Many manufacturers have recently gone to more realistic nominal sizes to reflect their WAM (width as measured) on modern rims with internal widths in the 19-21mm range. Buy a Conti GP5k, Schwalbe Pro 1 Evo, Pirelli P Zero Velo or a number of other recent releases and they'll measure under their nominal size on your narrow rims.