tyre pressure

Coach said:

do you just pump them up to what's on the tyre? I'm a big lad so I should
imagine I will need a shedful of air..

Personally, on road tyres to the maximum on the tyre, soft off-road
surfaces to about 1/3 of the way from minimum to maximum.

But there's no real science to it.

regards, Ian SMith
--
|\ /| no .sig
|o o|
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thanks

Nick

"Ian Smith" <[email hidden]> wrote in message
news:[email hidden]...

Quoted message said:

Coach said:

do you just pump them up to what's on the tyre? I'm a big lad so I
should
imagine I will need a shedful of air..

Personally, on road tyres to the maximum on the tyre, soft off-road
surfaces to about 1/3 of the way from minimum to maximum.

But there's no real science to it.

regards, Ian SMith
--
|\ /| no .sig
|o o|
|/ \|

Coach wrote on 25/11/2006 21:54 +0100:

Quoted message said:

do you just pump them up to what's on the tyre? I'm a big lad so I should
imagine I will need a shedful of air..
cheers

Depends. Road tandems to 30% over the max on the tyre, road bikes to
the max on the tyre and mtb tyres between 30-40psi depending on conditions.

--
Tony

"Anyone who conducts an argument by appealing to authority is not using
his intelligence; he is just using his memory."
- Leonardo da Vinci

In article <[email hidden]>

Coach said:

do you just pump them up to what's on the tyre? I'm a big lad so I should
imagine I will need a shedful of air..

Depends on the tyre, the rim, the surface and the type of riding - rock
hard tyres can reduce pinch punctures and rim damage, but softer tyres
can give a more comfortable ride and better grip. Front tyres usually
need less pressure than back tyres.

Coach said:

do you just pump them up to what's on the tyre?

When in doubt, yes. But use your own judgement if you're a bit more savvy,
based on what the tyre feels like when squeezed hard with fingers & thumbs,
the weight it'll be carrying and what compromise between comfort, traction,
speed and tyre life you want. In other words, use your intuition and
experience to make a guess.

For some models what's written is a sensible general recommendation, others
it must be meant as an absolute limit because it's so bonkers-high.
Sometimes you'll get an range instead of one limit. As well as your weight,
the kind of surface you're riding on makes a difference too.

Don't forget on most bikes that they'll be more weight on the rear so the
rear tyre should be harder.

Find more advice on www.sheldonbrown.com

~PB

Tony Raven said:

mtb tyres between 30-40psi depending on conditions.

Assuming those conditions are off-road... if you're riding an MTB
on the road, pump them up to the max (if you're not riding it
off-road, get some road tyres!).

Pete.
--
Peter Clinch Medical Physics IT Officer
Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital
Fax 44 1382 640177 Dundee DD1 9SY Scotland UK
net [email hidden] http://www.dundee.ac.uk/~pjclinch/

Peter Clinch wrote on 26/11/2006 09:31 +0100:

Quoted message said:

Tony Raven said:

mtb tyres between 30-40psi depending on conditions.

Assuming those conditions are off-road... if you're riding an MTB on the
road, pump them up to the max (if you're not riding it off-road, get
some road tyres!).

Why would I ride an MTB on road other than to get to off-road? I have
road bikes which are much better if I am staying on the road.

--
Tony

"Anyone who conducts an argument by appealing to authority is not using
his intelligence; he is just using his memory."
- Leonardo da Vinci

On 26/11/2006 09:31, Peter Clinch said,

Quoted message said:

Assuming those conditions are off-road... if you're riding an MTB on the
road, pump them up to the max (if you're not riding it off-road, get
some road tyres!).

Which is all very well, but to get off-road I have to ride on-road.
Pumping them up to the max is fine on the way out, because they can be
let down easily, but I'll be buggered if I'm going to pump them back up
to the max with a mini-pump just before I ride home :-)

Doesn't do much for tyre life though, riding knobblies on tarmac! Right
then, let's go and take a bit more rubber off...

--
Paul Boyd
http://www.paul-boyd.co.uk/

Paul Boyd wrote on 26/11/2006 14:15 +0100:

Quoted message said:

Which is all very well, but to get off-road I have to ride on-road.
Pumping them up to the max is fine on the way out, because they can be
let down easily,

Do you really honestly do that? What about the bits of road in between
the bits of off-road? Do you carry a gauge to check the pressure when
you let them down?

--
Tony

"Anyone who conducts an argument by appealing to authority is not using
his intelligence; he is just using his memory."
- Leonardo da Vinci

Tony Raven said:

Why would I ride an MTB on road other than to get to off-road?

I've no idea, but I /suspect/ that you're not the only person
reading this thread.

Pete.
--
Peter Clinch Medical Physics IT Officer
Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital
Fax 44 1382 640177 Dundee DD1 9SY Scotland UK
net [email hidden] http://www.dundee.ac.uk/~pjclinch/

Tony Raven said:

Paul Boyd wrote on 26/11/2006 14:15 +0100:

Quoted message said:

Which is all very well, but to get off-road I have to ride on-road.
Pumping them up to the max is fine on the way out, because they can be
let down easily,

Do you really honestly do that? What about the bits of road in between
the bits of off-road? Do you carry a gauge to check the pressure when
you let them down?

I tend to keep them pumped up more for the off-road too, tbh, even
though I know it isn't ideal, because ICBA to pump them back up.
My last off-road hack on the MTB was a ride-in for a remote Munro
in the 'Gorms preceded and followed by several miles of road from
and back to Braemar, and it would have been pretty daft to start
that all at low pressure.

Pete.
--
Peter Clinch Medical Physics IT Officer
Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital
Fax 44 1382 640177 Dundee DD1 9SY Scotland UK
net [email hidden] http://www.dundee.ac.uk/~pjclinch/

On 26/11/2006 14:19, Tony Raven said,

Quoted message said:

Do you really honestly do that?

Not any more - it was a hypothetical suggestion! Having said that, if I
was going to cycle any distance before any off-road, then I probably
would. Getting to my local woods doesn't warrant all that palaver.

Quoted message said:

Do you carry a gauge to check the pressure when
you let them down?

Well, actually, I used to! Then I just couldn't be arsed, plus I
changed to Presta valves and haven't got a suitable gauge. I got to
know what tyre pressures were right off-road without knowing what the
actually psi was, and just leave it at that.

--
Paul Boyd
http://www.paul-boyd.co.uk/

Peter Clinch wrote on 26/11/2006 14:38 +0100:

Quoted message said:

Tony Raven said:

Why would I ride an MTB on road other than to get to off-road?

I've no idea, but I /suspect/ that you're not the only person reading
this thread.

You mean there are people on urc who only have one bike? I don't
believe it! ;-)

--
Tony

"Anyone who conducts an argument by appealing to authority is not using
his intelligence; he is just using his memory."
- Leonardo da Vinci

I am having problems with my new crank bros alloy mini pump with guage.
It should be good for well over 100 psi.

To try it out, I deflated a tyre on my mtb. I could not get it above
40psi - generally the pump was coming off the valve and air was coming
out. On reconnecting, the pressure was down to 35psi, I would pump
again and the same thing would happen.

I then tried a presta valve tyre on my road bike. It was quite soft, 60
psi, and I wanted to inflate it to a humble 85psi. However, I could
only get air to come out but none to go in. Soon, the end of the valve
snapped off and disappeared, leaving the inner tube worthless.

This is the second mini pump I have tried to use. I couldn't get the
first one to work either.

Are these mini pumps generally thought to be difficult to use for
someone who is not very good at intricate work with their fingers, or
is there a fool-proof technique?

Until I have sorted this problem out I can't cycle further away than
walking distance from my house or an open bike shop. A real pain since
I will shortly be heading to Aus for a bike tour.

What does the panel think of the traditional pumps with floppy
adapters? These always worked without any trouble in the GODs. Can they
get up to the high pressure limits on tyre walls or are they just for
getting home in an emergency?

Thanks

Pete Biggs said:

Coach said:

do you just pump them up to what's on the tyre?

When in doubt, yes. But use your own judgement if you're a bit more
savvy, ........

Quoted message said:

Find more advice on www.sheldonbrown.com

Where Sheldon recommends that you don't automatically aim for maximum. Then
gives a useful table to get one started.

- Nigel

--
Nigel Cliffe,
Webmaster at http://www.2mm.org.uk/

raisethe said:

I am having problems with my new crank bros alloy mini pump with
guage. It should be good for well over 100 psi.

..............

Quoted message said:

This is the second mini pump I have tried to use. I couldn't get the
first one to work either.

Are these mini pumps generally thought to be difficult to use for
someone who is not very good at intricate work with their fingers, or
is there a fool-proof technique?

I find they work, but are fairly hard work. Need to hold both the pump,
valve and wheel rim in one hand, pump action in the other. I find it helps
if the wheel is loose (not always possible on some bikes).

Quoted message said:

Until I have sorted this problem out I can't cycle further away than
walking distance from my house or an open bike shop. A real pain since
I will shortly be heading to Aus for a bike tour.

So get a pump which works ?

Suggestions:
a) folding/collapsible track pump. Several makers offer these around 20-30
quid, they have a flexible connector to the tyre. eg. Topeak Morph range
(and other makers).
b) the Cyclair "pull" pump. Again flexible connector to tyre. Around £20
c) long frame pump, such as the classic Zefal HPX, or the Topeak Master
Blaster (I have one of these, its good). Have rigid connection to tyre, but
pump a lot quicker and more easily than short mini pumps.
d) compressed air cartridges. Normally I'd suggest these are really only for
those doing MTB racing, but perhaps they would work for you.

Quoted message said:

What does the panel think of the traditional pumps with floppy
adapters? These always worked without any trouble in the GODs.

I always hated the things, always leaked on me.

- Nigel

--
Nigel Cliffe,
Webmaster at http://www.2mm.org.uk/

Nigel Cliffe said:

So get a pump which works ?

Suggestions:
a) folding/collapsible track pump. Several makers offer these around 20-30
quid, they have a flexible connector to the tyre. eg. Topeak Morph range
(and other makers).
b) the Cyclair "pull" pump. Again flexible connector to tyre. Around £20
c) long frame pump, such as the classic Zefal HPX, or the Topeak Master
Blaster (I have one of these, its good). Have rigid connection to tyre, but
pump a lot quicker and more easily than short mini pumps.
d) compressed air cartridges. Normally I'd suggest these are really only for
those doing MTB racing, but perhaps they would work for you.

This is useful, thank you. I need a guage as I must have the tyres as
pressurized as is safely possible. I have just ordered a Topeak road
morph with guage. My Topeak Joe Blow track pump has been fine so
hopefully I will get on with this one too.

Tony Raven said:

You mean there are people on urc who only have one bike? I don't
believe it! ;-)

I only had one until '97. Up until then I had nowhere to store a
second and I used an EBC Country for everything: shopping,
commuting, touring and off-road.

Pete.
--
Peter Clinch Medical Physics IT Officer
Tel 44 1382 660111 ext. 33637 Univ. of Dundee, Ninewells Hospital
Fax 44 1382 640177 Dundee DD1 9SY Scotland UK
net [email hidden] http://www.dundee.ac.uk/~pjclinch/

raisethe said:

I need a guage

No one *needs* a tyre guage.

~PB