Heatwave tyre pressures.

[vickster]

Well I'm nowhere near 16st for a kick off and I'm certainly not a "noob" either.

so why run so high? 25mm Gatorskins are already fairly unforgiving. Drop to 90 and see how they feel? And do away with the heatwave tyre going bang worries too

 

[Oldhippy]

Never given it a thought or had any issues.

 

[mustang1]

I take my bike out of the studio and leave it outside for 20 minutes while I sort out my riding kit.

In that time, i figure theres enough time for air pressure from inside the studio to outside the studio to have stabilized in the tyres. I then pump the tyres to 95psi (25mm gp5000) and Im good to go. If the pressure increases due to excessive heat (either by braking or day temperature), I dont think it will make too much difference (no continuous long descents on my rides).

 

[Roadrat77]

I take my bike out of the studio and leave it outside for 20 minutes while I sort out my riding kit.

In that time, i figure theres enough time for air pressure from inside the studio to outside the studio to have stabilized in the tyres. I then pump the tyres to 95psi (25mm gp5000) and Im good to go. If the pressure increases due to excessive heat (either by braking or day temperature), I dont think it will make too much difference (no continuous long descents on my rides).

I store both mine in the garage which is like a furnace at the moment and when I checked the pressure before a ride on Friday morning it was way up on what it normally is so I deflated all four tyres straight away but I have heard of a few going pop even when stationary which got me thinking.

 

[mustang1]

Not a joe blow max by any chance? Those are hopeless for road tyres!

I have a Joe Blow (dunno what particular model though). Has it for 15 years and i used to pump my tyres to 120psi in those days (23mm).

 

[vickster]

I have a Joe Blow (dunno what particular model though). Has it for 15 years and i used to pump my tyres to 120psi in those days (23mm).

Specifically the max version (or I had a duff one)

 

[Big John]

Had one blow a couple of days ago in the garage. The wheel belonged to a mate, a carbon rimmed jobby. I put it down to the garage being like a furnace but everywhere is like a furnace at the moment. My sheds are even hotter. I checked the tube and it had split along one of the joins, quite a large hole. Before it blew it was at 80psi. I had one blow on the way home from a TLI bike race. The wheels were in the back of the car. It scared the living c**p out of me 😳

 

[bladesman73]

Well I'm nowhere near 16st for a kick off and I'm certainly not a "noob" either.

You shouldnt be anywhere near to 120psi then. I mean, each to their own and that and maybe you like the feeling or riding a Boneshaker?

 

[slowmotion]

Your tyre pressure will increase by a piddling amount in hot weather. No need to worry.

Lookee here......


View: https://medium.com/@matthew_vdh/how-much-will-my-bike-tyre-pressure-increase-by-on-a-hot-day-9fd76412a951

 

[rogerzilla]

Some tyres are perilously close to blowing off when they get to their maximum sidewall pressure (most have far more headroom). Schwalbe Duranos are one of them - they will pop off a rim at around 115psi. Those could be a problem in the heat if you'd put 110psi in during the cool of early morning. Add a bit of brake heat and you're in all sorts of trouble.

 

[T4tomo]

When I was cycling in the Alps and summer heat I often found that my tyres had gone from “a bit of give” outside the hotel in the morning to “rock hard+” at the top of a pass. Never had a blow out or any trouble.

Aren't the more likely to be hot at the bottom of a pass, hotter valley temperature and after being heated up by (rim) braking on the descent?

 

[byegad]

My first wife blew a Raleigh Shopper rear tyre off the rim. A long descent where she rode the rear brake all the way down, a bumpy unmade road and the BOOM! sounded like a cannon going off. The tube was in shreds and the sidewall split. I went to help and promptly burnt my fingers on the steel rim. I'd estimate the rim to be well over 150C.
On a similar topic the airline demands that tyres be deflated is a load of fetid dingo kidneys. Give sea level pressure is 14psi, at altitude it is less, but even a vacuum it will only add 14psi to the pressure! Take into account that at high altitude the temperature can be -40C and only a modest reduction below the maximum sidewall pressure should be fine.

 

[cougie uk]

My first wife blew a Raleigh Shopper rear tyre off the rim. A long descent where she rode the rear brake all the way down, a bumpy unmade road and the BOOM! sounded like a cannon going off. The tube was in shreds and the sidewall split. I went to help and promptly burnt my fingers on the steel rim. I'd estimate the rim to be well over 150C.
On a similar topic the airline demands that tyres be deflated is a load of fetid dingo kidneys. Give sea level pressure is 14psi, at altitude it is less, but even a vacuum it will only add 14psi to the pressure! Take into account that at high altitude the temperature can be -40C and only a modest reduction below the maximum sidewall pressure should be fine.

Yes I always tell airlines I've let the air out of my tyres - technically I have but only about 5psi. I'd much prefer air in the tyres to protect the rims in transit.

 

[All uphill]

Now it's cooler do I need to increase the pressure in my tyres?

 

[Hover Fly]

Aren't the more likely to be hot at the bottom of a pass, hotter valley temperature and after being heated up by (rim) braking on the descent?

But lower atmospheric pressure at 2000+ metres, and what’s this braking on the descent? When first setting off in the morning it’s cooler air and no braking yet.