pgjackson

I've always ridden 23mm tires, but am giving 25mm a try. My 23s are always pumped up to 110psi. What is the preferred psi for 25s? I am about 195lbs.

MinnMan

At a minimum you've been over-inflating your front tire. Classic Berto guide is here. Some may argue that his 15% deflection is arbitrary, but it does show the offset as a function of nominal tire width. Note that x axis is weight/wheel, not total weight.

VicBC_Biker

Try:
https://axs.sram.com/guides/tire/pressure

datlas 

I would drop your PSI to about 90F 95R. You could possibly even go a little lower but depends on road quality too.

Why are you pumping your 23's to 110? Seems kinda high.

GhostRider62

I run 89 psi F/R. 25 mm GP5000

My TT front wheel is 23 mm and I run it at 100 psi

cxwrench

If you want the same feel run 10psi less per jump up in tire size. 110 is too much in a 23, I'd start at 90ish for the 25mm tires, and depending on your bar to saddle height relationship adjust the front down some the higher the bars are.

jaxgtr

When I run 25, my front is 90 and rear is 95 and I range between 190 and 200. Depending on what kind of ice cream I buy

urbanknight

I'm ~200lb and was running 90/100 on my 23's until last year when I switched to 25's and dropped to 80/90. They're doing great with a much smoother ride.

Branko D

On Victoria Corsa Speed TLR in 23mm I prefer 95 to 105 psi depending on road quality, on GP5000 TL in 25mm I prefer 90 to 100 psi.

Roughly 72kg, the roads around here vary, but are mostly decent, running everything tubeless now with airliners (a chore to fit, but brilliant) on some 19mm internal rims.

shelbyfv

Here's another guide https://silca.cc/pages/sppc-form

pgjackson

According to this my 110 psi is right on the money for 23mm (maybe a few pounds less on the front). For the 25mm its 96psi on the rear and 93 on the front.

big john

I used 23s on everything for 30+years and always 100/110. Last year I switched to 25s and lowered the pressure a bit, 95/100, but don't like a squirmy feel.

We have some really beat up streets here and I don't notice a huge difference in the ride except on chip seal where the 25s do feel smoother. I'm under 200 pounds now but had been 220 for years.

Jack Tone 

When I raced criteriums on smooth surfaces, I weighed 220. I used 23's on Mavic O4CD's and ran 140 front and rear according to my Silca floor pump. Now I weigh 210 and with 25's it's 115 rear 110 front. (still on narrow rims).

pgjackson

My plan is to keep the 23 up front at around 100psi and and put a 25 on the rear around 95-100 psi and see how I like it.

canklecat

I favor the lowest recommended pressure, but I weigh 150 so pinch flats aren't a risk unless I run over a brick... which I've actually done once to dodge being pinched by a couple of trucks that bottlenecked me.

Mostly I favor lower pressure because our default pavement is the coarsest chipseal I've ever seen, more like railroad ballast in epoxy. With an old neck injury that stuff is painful to ride for long with high pressure skinny tires.

Also depends on the tire and tube. With latex tubes and good tires I can run slightly higher pressure and still feel comfortable on our coarse chipseal.

Generally with 700x23 and x25 tires I use around 60-75 psi front, 75-90 rear. Depends on the tire, tube, and my mood. Sometimes I'll start with slightly higher pressure, then stop and bleed off some air during the ride if it feels too harsh. I try to avoid running pressure so low that it feels mushy or imprecise on fast curves.

biker128pedal

Did you use the measured tire width at the pressure? I have GP5000 tires on 25mm inside width rims. Front is a 25mm and rear a 28mm. At pressure the front is 29 to 30 mm wide. The rear is about 31mm. So I run 80 rear and 75 front for me at 230 lbs me and bike.

Branko D

25mm internal width rims are unusually large for road rims, though, so that's really quite like having a tire size up - if not a slight bit more - over a 19mm internal rim which is probably around what most people have on their road bikes.

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pgjackson

I don't want to get that scientific about it. The front tire says its a 23 and the rear says its a 25. That is close enough for me.

biker128pedal

Just means you can work your way down to smooth it out. At least until you get a pinch coast. With 19.5 mm inside road wheels (which I have planned for my disc brake bike) anything less than 90psi for. 23mm GP5000 and I’d get a pinch flat. Then I’d run 110psi.

Bob Ross

Yep, ^^^that's the rule of thumb I've been using for years.

fwiw when I first started serious [sic] road cycling >15 years ago I was pumping 23s up to 115 or sometimes even 120psi (!) I quickly learned that the ride was much nicer at 110psi...and then after a few years of that, found that 100psi seemed to offer me the best combination of comfort, performance, and road feel.
(Amazingly I have been ~175lbs for the entirety of all ^^^those experiments. And still am, knock on wood.)

So yeah, my 23s are at 100psi, my 25s are at 90psi. Been like that for about a decade now.

pgjackson

First ride with the new set up yesterday. Front a 23 and the rear a 25. Both at 100psi. Ran really nice. Might try dropping the front down to 90-95.

rumrunn6

I used to go by feel, but now I use a gauge. I run the front a little lower than the back. I'm 225 lbs & I run my 25mm road tires approx. 80-90 psi front 90-100 psi rear. I switched from 23mm tires a handful of years ago & don't remember stressing about exact pressures, going from one size to the other. from what I've read, personal pressure choices are not a precise requirement. meaning it's up to the individual rider, bike & tires. but I think a light guy compared to a heavier guy like me, would be happy w/ lower pressures than what I use, all other factors being equal, which of course, they would never be. good luck finding your equilibrium!