Air pressure road tyres

billyhead

Just curious for those who commute how often do you pump up your road bike tyres. Do you do this out of habit every day before you leave or pump them up once every 2 or 3 days etc. I have a 13km each way commute to work starting from next Monday and was wondering should I pump 110-120psi every morning into the 2 tyres?

cython

I do a similar commute and once every 2-3 days is typically plenty, though I've gone a week before without pumping them when I've felt particularly lazy! Would usually pump to between 110 and 120 PSI when inflating them.

Cee-Jay-Cee

110-120psi? I run my tyres at 80f/90r and theyre more than 'hard' enough at that. Any harder and they make the ride crashy and uncomfortable.

As for when you should pump them...when theyre soft. If they only loose a few psi each day then theres no real need, every 3rd or 4th day will suffice. I dont commute by bike but i'd say I only pump my tyres once a month and the bike would be used 3 to 4 times a week for short spins (100-150km in total)

Darkglasses

billyhead wrote: »

Just curious for those who commute how often do you pump up your road bike tyres. Do you do this out of habit every day before you leave or pump them up once every 2 or 3 days etc. I have a 13km each way commute to work starting from next Monday and was wondering should I pump 110-120psi every morning into the 2 tyres?

I pump my commuter tyres at the start of every week. 90 PSI is fine for me. Depends on your weight but 110-120 is very much the top-end.

ted1

Pump every Sunday night, usually up to 120PSI. Have a 30km commute each day.

crosstownk

I pump my tyres every 3 or 4 days. As stated above, I don't pump to max to allow for some comfort especially as I commute across Dublin City. I aim for a happy medium between min and max to avoid pinch flats. Usually I pump closer to max than min.

Pressure will depend on tyre size and recommended pressures.

koutoubia

Have a set of Wheels woth brand new Vitttoria tyres and tubes. Left the in the shed for the best part of 6 months. When I eventually took them out and pumped them up they were still at 50 psi.
Lash 110psi into them and once a week form there on in!

Alanstrainor

Once a week, and 120psi for me, covering 25km a day, 5 days a week.

Wishbone Ash

For the commute bike I usually check every 2 days or so and always 120psi. (Occasionally I neglect to do so but usually know when the ride feels more comfortable than usual.)

For the other bikes, I check before every ride and again 120psi. Also check the tyres for debris before every ride.

LpPepper

Depends on the tyre but for Road tires I would try at least 100PSI. Try 100 in front and 110 in the back. Keeping the pressure high lowers your chance of a puncture - I often hear stones or whatever being flung away by the tire !

The Sidewards Man

I do 145psi.

Alek

28mm tyres, 80psi back, 70psi front, sometimes less - I check every week or so. I'm 80kgs myself and my avg speeds are 27-29kph via city centre. Very comfortable ride. Whats the story with that high pressure at all?

Wishbone Ash wrote: »

120psi.

Wishbone Ash wrote: »

120psi.

Keeping the pressure high lowers your chance of a puncture

Not for WA :P

ZiabR

110psi front and back from me.

Carawaystick

8 bar
metric manometer on my pump.

route66

Came across this somewhere - pressure determined by tyre size and overall weight on each wheel:

Alek

This is the chart I'm using (well, not exactly, but gives very similar results). Works very well for comfort AND speed.

equivariant

I have a 15k commute each way. I pump about twice a week - always check on mornings when I'm on a tighter deadline (so punctures would be more stressful). I run 110psi in good dry conditions and 100 when its wet. Also check the tires for debris and damage before you start - that is really important for puncture avoidance.

NeedMoreGears

Once a week 110/100 on 25mm tyres before the weekend spin. Usually down to around 90/80 by the end of the week, after three or four 40km commutes.

G1032

Don't commute but pump tires before every spin and to 100 psi front and back.

SetOverSet

I use 25mm Vittoria Open Pavé and the recommended pressure is 100-130psi. I pump them at the start of the week before commute and again before weekend club ride - usually around 110 front and 120 rear in dry conditions or 100/110 wet.

nialljf

is more pressure in back tyre the done thing? i presume it's down to more weight on the rear wheel. is it more comfortable to do this?

Wishbone Ash

nialljf wrote: »

is more pressure in back tyre the done thing? i presume it's down to more weight on the rear wheel. is it more comfortable to do this?

Some put more in the rear as it takes more weight - probably 60% weight on rear wheel, 40% on the front. Increased pressure wouldn't make it more comfortable - it would be the opposite. Low pressure is much more comfortable but greatly increases chances of puncturing.

Alek

Low pressure is much more comfortable but greatly increases chances of puncturing.

Is there any scientific explanation of this or is it rather old wife's tale?

Somehow I cannot imagine physics behind it. Think about a baloon - is it easier to pop one that is pumped hard or the floppy one?

Lumen

Alek wrote: »

Is there any scientific explanation of this or is it rather old wife's tale?

Somehow I cannot imagine physics behind it. Think about a balloon - is it easier to pop one that is pumped hard or the floppy one?

Smaller contact patch means you're less likely to roll over the spiky thing.

Alek

With my soft 31mm tyres I should be getting one after another then, cycling daily through the city centre. Yet I may get one in 6 months or so.

And I was getting a lot on 23mm vittorias (open corsa) - like every two weeks.

cython

Alek wrote: »

Is there any scientific explanation of this or is it rather old wife's tale?

Somehow I cannot imagine physics behind it. Think about a baloon - is it easier to pop one that is pumped hard or the floppy one?

A lot of the concern comes from snakebite punctures, and to use your own example, the easier it is to bring the the rim into contact with the "far" side of the tyre, the easier for that to happen, and a softer balloon is more easily compressed in this manner (2 points on the surface brought into contact with each other). However tyres are generally manufactured to not simply explode under increased pressure, which is where the balloon analogy fails.

Wishbone Ash

Alek wrote: »

With my soft 31mm tyres I should be getting one after another then, cycling daily through the city centre. Yet I may get one in 6 months or so.

And I was getting a lot on 23mm vittorias (open corsa) - like every two weeks.

Are the 31's a 'puncture resistant' tyre type? To do a proper comparison, you'd have to compare different widths of the same make/model.

cython wrote: »

....However tyres are generally manufactured to not simply explode under increased pressure, which is where the balloon analogy fails.

Exactly - balloons get thinner and therefore weaker as they inflate.

A hard tyre is also more likely to reject debris whereas a softer tyre may absorb it.

Alek

Are the 31's a 'puncture resistant' tyre type?

Its the GP4000S II 28mm, 31mm measured. I guess they have some basic protection, but nothing fancy.

A hard tyre is also more likely to reject debris whereas a softer tyre may absorb it.

I have a gut feeling its the other way around, hard tyre doesn't have much give against the debris, while a soft one can stretch and "go over" a sharp piece.

Again - imagine a soft balloon against a pin, it will resist the pressure for much longer. Not because the rubber is thinner, but because its surface can stretch and "avoid" it.

ford2600

https://fairwheelbikes.com/c/media/2013/01/H-Plus-Son-TB14.jpg

On a recent touring trip approx 700km, with bike/panniers/water/rider just north of 100kg I forgot to pump tyres with track pump at start(4.30am starts do that:D) . Remembered it 3 days later puncture free over the 700km. 60psi was reading on 25mm tyre

Wider rims definitely help to make snake bits less likely.

Low pressure is the business for comfort, you can have your carbon seat posts and all the rest of it