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My mate who has luddite tendencies got a bike (Giant Defy) that came actually tubelessed, with sealant and all. 700x32c. He had a puncture that didn't seal, so he took the tyre off and added more, then failed to get it to reinflate. After a week of cursing and swearing online, he managed to get it inflated but the tyre (with a bit of tubeless thread in the hole) only holds air to 50psi apparently, in the workstand.
Turns out he was expecting to be able to inflate to his usual 120psi..! So I told him he needed much lower pressures. But how much? He's 73kg, so I thought 50psi in a 32c might be enough?
inflated but the tyre (with a bit of tubeless thread in the hole) only holds air to 50psi apparently, in the workstand.
Either way needs to fix that - asking for trouble riding that.
My experience is that tubeless thread is worse than useless for road tubeless. 70ish psi and it ****s off for orbit. It actually held more with sealant alone !
Moved to dynaplug now and I prefer still to patch them old school from the inside.
700/25 tubeless and I run 90psi at 85kilo rarely need topped up more than I would have with tubes anyway.
Ive tried them lower and they just squirm when ridden hard.
About 80 PSI front and rear on 700x28 Hutchinson Fusion tyres, DT Swiss Alu rims, I'm around 79-80kg. Needs topping up fairly regularly.
67kg, Mavic Open Pro Disc, Mavic Yksion 28c.
55PSI front, 60-62PSI rear.
120PSI on 32c is shockingly and unnecessary high...
Cheers!
I.
I run 85 psi on 25mm tyres and weigh 66kg. Apparently that's quite high for my weight but feels fine to me. I'd be running closer to 100 with tubes in.
50psi in 32mm tyres seems at the lower end of what I'd be riding, but since I don't have 32mm tyres set up tubeless others are probably better qualified to comment.
This might be a good starting point: https://axs.sram.com/tirepressureguide
Suggested I run a few more PSI in my gravel bike's tyres. Felt counter-intuitive, but it made the bike feel more lively. Which is nice.
64kg, continental 5000 25 mm 72 front, 78 rear
85kg, GP5000TL 28mm, 70f, 75r
Im 72kg and also use 32mm tyres. I tend to use 60 front and 65 rear. Or 55 front and 60 rear for an smooth ride. That’s on 20-22mm wide (internal) rims.
85kg, run 80psi in 25mm tyres with tubes.
Think I run 50psi in 32s on my winter bike, also with tubes!
So he should be able to run 50psi easily if he's 73kg. 120psi must have felt awful...
edit: for completeness I also run 40psi in 40mm gravel tyres.
I'm 63kg and run the following tubeless
30MM = 65psi
23MM = 75psi
&
37psi on 40mm Gravel tyres
63kg, 25mm pro ones that measure as 28 on a wide hookless rims. 65 psi.
Personally if you mate is a luddite and rides mostly on the road then just switch back to tubes. I’m ok with road tubeless but I don’t recommend it to people unless they have other experience and know what they are doing. But yes lower pressure is better.
110 KG
Road: 28c GP 5000's - 90 psi
Gravel: 40c Ramblers - 60 psi rear, 55 psi front.
IF I can get away sub-100 psi on the road, anyone can.
84kg 25mm internal rims; 44c tyres 35f/45r. 33c tyres 45f/55r
125psi on a 32c tyre is probably way over the safe limit for both the tyre and rim. Could be both expensive and painful.
I'm 70kg and use 65/70 psi for GP5000 on Giant SLR-1 carbon rims - the old ones (2017), not the new hookless ones.
About 66kg and I run 70psi in Hutchinson 25/28C. Nice balance of grip and speed.
About 85kg and 90psi in GP5000TL 25C. Could probably get away with a bit less but I really don’t enjoy the squirmy feeling.
65kg and running 65f, 75r on Schwalbe Pro One 28mm. No issues at all so far over thousands of km. This is the second set of Schwalbe Pro One on those rims.
On the CX with 38mm Schwalbe G-One is's about 40ish but the rear in particular is incredibly sensitive to pressure - maybe it's to do with the frame and wheel combination but a few PSI either way can have it bouncing around almost uncontrollably vs bottoming out and squirming almost uncontrollably.
120psi in a 32mm tyre is insane. Actually I think it was Giant who said that one of their biggest challenges with selling bikes already tubeless was convincing shop mechanics not to inflate them so high.
80 kg, (plus ahem about 5kg of lockdown cake) and run 75 front and 80 rear on 25mm Vittoria Corsa G+. I could run lower, but it makes me nervous when leaning the bike over on fast descents. I've tried as low as 65f and 70 r on this set up when going slower, works but feels odd Used to run 32mm G-ones at about 55 for road, 45 for commuting/gravel. Anything north of 65 was like riding on solid tyres.
Only ever run 120 psi once - for a 10mile TT. Most uncomfortable experience ever and most definitely slower since the bike skipped and bounced over every crack/rough surface. Ran 90psi in the tubed equivalent on the Corsa's, 80 psi on tubed Conti's
WRT not getting past 50psi when repairing a puncture - I had a corsa G+ Control that was like that - add sealant, pump up to 60/70, ride around the block, pump up again, ride around the block again and leave with the hole at the bottom overnight - was fine after that.
I'm ~79Kg, bike with 3l water is ~11.5Kg, I run rear 28mm (really 31mm+) GP4000S II with a tube @75PSI.
At ~73Kg and tubeless, 50-60PSI should be fine with a 32mm measured tyre.
60-80psi in 25s, 80kg
Normally run schwalbe G-One Speed 35 c 40psi front and 46psi rear.
Have changed to GP5000 32c at the weekend and running those at 48psi front 56 psi rear, felt supple enough without feeling soft so pretty happy as a first stab at pressures.
I'm 77kg.
I run around 60 front and 70 rear in 30/32mm Roubaix when I bother to pump them up, can go as low as 40 on same set up if commuting.
I have Panaracer gravelking in 32 and max tubeless is 60psi. I run mine at 40-50psi which gives a comfy ride in 82kg ish.
I do find that at higher pressure sealed holes can start to leak again as the pressure goes up and when I do get punctures I notice the pressure will drop to 20 psi ish. This doesn’t make it Unrideable just feels a bit soft. Being able to get to my destination with out stopping when commuting is a god send.
700/32 front, 28 rear
I'm 78kg and the bike's about 10-12
front 60ish, rear 70ish
90kg here and have the distinct advantage of working for a tyre manufacturer, but by the same token, I also sympathise with those above who have stated that they don't like a tyre that squirms.
My rule of thumb is this... On a 25c tyre, setup tubeless, put your body weight in kg as the pressure in psi in the rear tyre, and run the front about 5psi softer. As such, I run 90psi in a 25c tubeless tyre on the rear, and 85psi in the front. I could go softer, but it starts to feel a bit squirmy. If running tubes, add 10psi roughly.
For a 28c tyre, then reduce the pressure by a proportional amount. As such, on my steel bike with 28's, I run 80psi rear and 75psi front (tubeless again). My GF's about 83kg, she's running 75psi rear and 70psi front on 28c tyres on her bike. She has some winter wheels with 30c tyres and runs 70psi rear and 65psi front on those...
Not only is 120psi in a 32c tyre ridiculous, it's also highly dangerous! I don't know of a 32c tyre that's rated to more than 100psi, nor a rim that will take that kind of pressure with a 32c tyre fitted. At 90kg, if I was running 32c's on road setup tubeless, I'd start with around 65-70psi in the tyres myself, and go from there. The OP's friend at 73kg should be looking at around 55-60psi in 32's by contrast I'd suggest.
FWIW, I did an unscientific test on my local 20 miles loop recently, my 7.5kg Colnago on 25c tyres and my 8.5kg Genesis Volare steel bike on 28's (of the same tyre, wheels were very similar too though not exactly the same), and found that the steel bike on the 28c tyres was actually very slightly faster, and a lot smoother... Don't get me wrong, the Colnago feels more engaging, and on smoother roads I have no doubt it's faster, but the road surfaces are less than impeccable round here and you can't argue with the stopwatch!
70kg 25mm tyres 75psi rear 70psi front