Road bike tyre pressure...

Discostuy

Hi all,

Bit of a daft question but...

How often should I need to be topping up the pressure in my bike tyres?.
I've noticed after a cycle or after a few days of non use, the pressure seems to drop 20-30psi.

Is this normal, or is it a sign of slow puncture?

The bike is new enough (about a month or so old), so the tires and tubes are brand new.

Thanks.

Alanstrainor

My tyres will deflate that much in about 2 months of use, not 2 days. Something's not right there.

ednwireland

the higher i pump mine the more pressure they seem to lose when i put them up to 130psi they seem to lose the bit to 100psi pretty quickly then the rest slower
(dont know if that helps)

last sunday though one was down at about 50 psi pumped up and the tyre had a slow puncture after 50km (luckily i was nearly home)

Unregistered.

I usually top up mine every 2 weeks. In that time, pressure would be down from 120 to about 105 psi.

Dermot Illogical

I pump mine every day. But then I like to keep them up around 130-140psi.

Discostuy

Yeah its an odd one. They drop a bit, but then balance out so I don't think its a puncture?.
Maybe they are cheap tubes that came with the bike and just aren't holding the pressure well?

AaronB

I keep mine at 120, pump them before every cycle. it would drop about 10psi each long cycle

Cee-Jay-Cee

Mine drop 20-30psi over 7 or 8 weeks. I check them everytime I head out for a spin.

Greenman

6 bar, every sunday evening.:)

Lusk Doyle

Discostuy wrote: »

Yeah its an odd one. They drop a bit, but then balance out so I don't think its a puncture?.
Maybe they are cheap tubes that came with the bike and just aren't holding the pressure well?

The only difference between a cheap tube and an expensive tube is the label that they get slapped with when exiting the (same) factory.

C3PO

CJC999 wrote: »

Mine drop 20-30psi over 7 or 8 weeks. I check them everytime I head out for a spin.

Does that mean you only ride your bike every 7 or 8 weeks?

RidleyRider

Dermot Illogical wrote: »

I pump mine every day. But then I like to keep them up around 130-140psi.

What tyres and tubes are you using to go that high with pressure?

ashleey

My continentals say a max of 120 psi

RidleyRider

ashleey wrote: »

My continentals say a max of 120 psi

Ditto with my schwable and vittorrias. He might be on tubs though.

Lusk Doyle

RidleyRider wrote: »

What tyres and tubes are you using to go that high with pressure?

ashleey wrote: »

My continentals say a max of 120 psi

RidleyRider wrote: »

Ditto with my schwable and vittorrias. He might be on tubs though.

I always keep mine at 130 each time I pump. I use normal €4-5 tubes and either panasonic panaracer tyres or continental GP4000s. No issues.

With tubs you can get much higher than that.

doozerie

I have latex tubes on one bike and they lose, I'd guess, about 10% or more of their pressure per night. My butyl tubes take weeks to lose as much as 10%. All of my tyres are inflated to 100psi.

Check to make sure that the threaded head on the valves is closed properly. Some tubes seem to be fine with those only very lightly threaded closed, others seem to need them reasonably tightly closed.

easygoing39

Pump mine once a week,the wife twice a week usually.

el tel

You're probably pumping them with poor quality air. Try using an Assos pump; Swiss air has better purity and optimal nitrogen content.

Cookie_Monster

ashleey wrote: »

My continentals say a max of 120 psi

RidleyRider wrote: »

Ditto with my schwable and vittorrias. He might be on tubs though.

but they'll have the usual modern safety limits built in, somewhere around 50% I imagine so 140 should be no bother.

murph226

115-120 is as high as I go, check it every few days, doesn't drop much.

smacl

easygoing39 wrote: »

Pump mine once a week,the wife twice a week usually.

We're still talking tyres here, right?

ednwireland

RidleyRider wrote: »

Ditto with my schwable and vittorrias. He might be on tubs though.

my vittoria diamante pro's and rubino pros are 145psi max

Dermot Illogical

RidleyRider wrote: »

What tyres and tubes are you using to go that high with pressure?

Tubes are whatever I get handed in the LBS. Tyres are vittoria rubino pro on one bike, zaffiro on another. Both havea 145 max.

kingoffifa

Lusk Doyle wrote: »

The only difference between a cheap tube and an expensive tube is the label that they get slapped with when exiting the (same) factory.

just curious - do you really think this is true? That tubes are all the same? I can't say for certain but I found Schwalbe tubes seem to not need to be pumped as often as other tubes i have had.

FISMA

Discostuy wrote: »

How often should I need to be topping up the pressure in my bike tyres?.
I've noticed after a cycle or after a few days of non use, the pressure seems to drop 20-30psi.
Is this normal, or is it a sign of slow puncture?

Discostuy,
What pressure are you using and what size tires?

I normally run about 110lb/in² and find that it is normal to have to top them up every few days/

No tube has a perfect seal and at high pressures such as these, loss over the course of two or three days is to be expected.

I wouldn't expect to be losing that much overnight though.

easygoing39

smacl wrote: »

We're still talking tyres here, right?

Yes,LOL,its just she blames low tyre psi,dry chain,my brakes are rubbing etc etc,to disguise the fact that she's not training enough!If she had as many excuses to avoid sex I'd have left her years ago.

triggermortis

I pump my commuter tyres every other week (as I work every other week) to 110psi and check my home bike every time I go out on it.
If you use a CO2 pump, it will leak off and need to be topped up.
I did take my bike into work one day and pump the tyres with nitrogen to see if it made a difference, but it didn't. A week later they still needed a top up

Lusk Doyle

triggermortis wrote: »

I pump my commuter tyres every other week (as I work every other week) to 110psi and check my home bike every time I go out on it.
If you use a CO2 pump, it will leak off and need to be topped up.
I did take my bike into work one day and pump the tyres with nitrogen to see if it made a difference, but it didn't. A week later they still needed a top up

You have a home bike?!? Must be some distance to the east wing in your pad then?

Donelson

Maybe it's the pump heating up the air before it goes in to the tire, i've one of those old barrel type pumps and it can be pretty hot by the time the tube is full.

Discostuy

FISMA wrote: »

Discostuy,
What pressure are you using and what size tires?

I normally run about 110lb/in² and find that it is normal to have to top them up every few days/

No tube has a perfect seal and at high pressures such as these, loss over the course of two or three days is to be expected.

I wouldn't expect to be losing that much overnight though.

I pump them to 110psi.
Tires are continental ultra sports (700x23).

I had the bike out today, so am going to check them tomorrow and see how they are. Hopefully they are ok!

FISMA

Discostuy wrote: »

I pump them to 110psi.
Tires are continental ultra sports (700x23).

I had the bike out today, so am going to check them tomorrow and see how they are. Hopefully they are ok!

If you have conti tubes then you have the same setup as I. 10-20psi once or twice a week is not a slow puncture and to be expected. Just squeeze them before a ride to ensure they're fine.

denbatt

Tire pressure will vary on weight and road surface you travel really, I was speaking to a guy the other day, who has ridden the RAS he weighs 63kg and never runs more than 80-85psi, I always rund between 100-120, i am 75kg, and sometimes find the 120 can be a rough ride on the west cork roads! Re; tubes I have tried several brands, I wouldnt say more expensive is better, they all get binned after a puncture anyway.

smacl

Originally posted by Lumen AFAIK, which is based around weight (combined bike + rider) on each wheel, which will of course change with riding position and gradient. I aim to run ~105 back and ~95 front on my 25mm Durano plusses, although tbh I don't trust the pressure gauge on my blow joe track pump to more than plus or minus 10%

Lusk Doyle

smacl wrote: »

Originally posted by Lumen AFAIK, which is based around weight (combined bike + rider) on each wheel, which will of course change with riding position and gradient. I aim to run ~105 back and ~95 front on my 25mm Durano plusses, although tbh I don't trust the pressure gauge on my blow joe track pump to more than plus or minus 10%

We aint all skinnies! Feck sake, the graph stops at 70kgs!!!

smacl

Lusk Doyle wrote: »

We aint all skinnies! Feck sake, the graph stops at 70kgs!!!

That's total weight per wheel, e.g. 50% front and back with a 10kg bike, the chart would work for a 130kg rider. I'm reckoning 70/30 split going up hill on a steepish gradient worst case, so me 80kg plus my bike at 10kg = 90kg, 70% = 63kg on the rear whee, which comes out at about 105psi for 25mm on the chart.

Also kind of suggests to me heavier people going up steep hills ought not to be running 23mm tyres. YMMV.

joxerjohn

I like Michelin A1 Air stop tubes they hold air pressure very well I find. Often very good offers on CRC.