MinnMan

So, what's the recommended pressure for this tire.

Donnelly bought Clement and as far as I can tell, it's basically the same tire with a different name. But the labeling recommends contradictory tire pressures. the label and the raised text on each tire contradict one another, and the different tires say different things on the labels

(for the record, I run these at 70 psi when I'm riding mainly on pavement, and 50 psi on gravel)

Here's the label on a Donnelly XPLOR USH 700X 35 mm 120 TPI tire. It says 40-60 psi.


Here's the raised text on the very same tire. 65-105 psi



Here's the labeling on an old Clement, which again, I think is essentially the same tire (55-90 psi)


And here's the raised text on that tire (65-105 psi, same as the Donnelly)

DeadGrandpa

A perfect example of why you can't believe everything you read.

mstateglfr 

Donnelly didnt buy Clement so much as it leased the rights to the Clement name for a number of years from Pirelli Tire. Pirelli was getting into the bike tire game and would have competed against its own brand.
Since Donnelly owned the actual tread patterns, they chose to end the licensing and produce under their own name.


As for your tires, I would ignore all the info on the sidewalls as some if it is based on a formula for when a tire blows off the rim, so its largely meaningless. Well I take that back- the 40-60 seems reasonable in the first pic. If you are running with tubes, stay higher than you otherwise would tubeless. Pump em up and test different pressures based on your weight and how you like the tire to feel on pavement as well as gravel.
For me at 215#, I would be in the 55-65psi range, depending on riding surface. I have 35mm slicks on a bike that sees almost all pavement and its about 65psi when I stop pumping.

chas58

Wow, good catch.

I can't see the whole embossed part, but typically mine state the max PSI, which on a beaded rim may safely be 90 PSI (105 sounds kinda extreme for a 35mm tire!!!).

Where 5 years ago, 60 to 90 PSI was the norm, today's enlightened rider will typically use the range 40-60 psi for that same tire.

But of course that all depends on the wheel you use and the weight of the rider. ENVE does the best job of outlining this for their rims that I've seen (if you get into a multi-dimensional matrix).

Then there is this - many of the carbon rims for gravel these days are hookless, and I wouldn't go over 60psi in those no matter what (Industry standard is <= 5bar). I wouldn't go over 60 PSI on anything without a tube for that matter, hooked or not. But yeah, some of my tires would be safe at 100psi with a tube and a hooked rim, but I'm never gonna go over 60psi in them 'cause I'm not hooked or tubed.

MinnMan

So I'm guessing that the change from 55-90 psi to 40-60 psi partly is just bowing to the new fashion of lower pressures. Still, the two ranges barely overlap - which is kind of odd, I think.

I get that the raised text on the sidewall is usually more of a safety maximum limit, but in that case, I don't see why it's specifying such a wide range (65-105 psi). I suppose that the maximum advisable pressure could vary depending on rim width or tubed vs. tubeless, but by that much?

It's true that when I run the tires at 70 psi (tubed), they are fast but somewhat harsh. I could probably get away with lower pressure on paved roads. I weigh 160#.

chas58

IMHO, the only number that matters on a sidewall is the MAX pressure, if listed as such. Even then I'm never gonna get near it (outside of the velodrome at least), so even that is irrelevant. The low pressure range is meaningless. They can be used as a guideline for people who don't geek out on their bikes.

for you, I would do 45-55 on the road, maybe 35-40 off road (often I use the lower number for my front tire and higher for my rear to match the weight balance of the bike; besides the front gives flotation and comfort, and the rear affects the speed/power the most).

This chart started the whole low tire pressure thing, but its still pretty accurate for gravel (its probably a little low for very fast road riding).