presta valves

Pat wrote:
Furthermore, your pre-ride pump-up is the perfect time to
safety-check your wheels and tires: check for loose bearings by
shaking the wheel side-to-side; spin the wheels and look for
out-of-true wobbles (use brake pad as stationary reference
point);
iInspect the tread for cuts, bulges, abrasions, any other
anomalies.

I don't agree with you here; I think the best time to safety check
the
wheels and tires is post-ride. After all, there you are in the
pre-ride, ready and dressed to go riding---and suddenly you see a
slit in the side wall. Inspect post-ride and you have time to get
things fixed before the next ride. I check my tires after a ride
when
I put the bike on the rack on the back of my car. The bike is at
eye
level and it's a good time to do it.

But you still have to do a pre-ride check, in case there's a slow
leak -- or, if you left the rack trunk open and there's a cat in it


--
Mike Kruger
"When cryptography is outlawed, bayl bhgynjf jvyy unir cevinpl." -
Anonymous

But you still have to do a pre-ride check, in case there's a slow leak --
or, if you left the rack trunk open and there's a cat in it

--
Mike Kruger

My pre-ride check consists of me squeezing the tire between thumb and
forefinger....

"Andrew Price" wrote in message
...
On Thu, 12 Jun 2008 00:52:28 -0600, mark wrote:

Narrow, high pressure tires need reinflating more often than wide, low
pressure tires. Thickness of the tube probably has an effect, as would
the quality of the valve. FWIW, I top off my road bike's tires (700x23)
before every ride, but I will go a month at a time without reinflating
my touring bike's tires (26 x 1.75"). Both have Presta valves.

Also my experience - well, almost. I usually manage to do 2 to 3 days
(around 40km per day) between topping up my 700x23 road tyres (which I
run at 9 bar). The touring bike, with 700x40 tyres inflated to 4.5
bar, goes at least a month before needing a top up.

All of these responses have been very helpful. I ride everyday at least 20
miles a day.
I will stop worrying and just check them every day. Thanks.

Pat wrote, On 6/12/2008 10:23 PM:
But you still have to do a pre-ride check, in case there's a slow leak --
or, if you left the rack trunk open and there's a cat in it

--
Mike Kruger


My pre-ride check consists of me squeezing the tire between thumb and
forefinger....



I do that too. But, I also like to give my wheels a spin and see if they
are running true and look for any bulges in the tires. It only takes a
few seconds.

--

Paul D Oosterhout
I work for SAIC (but I don't speak for SAIC)

My pre-ride check consists of me squeezing the tire between thumb and
forefinger....


I do that too. But, I also like to give my wheels a spin and see if they
are running true and look for any bulges in the tires. It only takes a few
seconds.

Paul D Oosterhout

Okay, that's good---but I am NOT going to check my tires' air pressure every
single dang day! That's being obsessive about it. So what if the air
pressure has gone down 2 psi? or even, gasp, 5 psi?

Pat in TX

On Jun 11, 8:25*pm, "mary" wrote:
Is it just me or do tubes with presta valves have to be filled up more
often? *It seems like once a week I have to top off the air in the tubes..
Just wondering. Oh and before you ask, yes I make sure the valve is closed
all of the way after filling.

The tubes themselves leak a little air. Thinner, higher pressure tubes
will be worse about this. I've tried a lot of different brands of
tubes and lately have been using the Schwalbe standard tubes. They
seem to leak less air than the others and seldom need topping up.

Smokey

"Burr" wrote:

If you are real light you can run less air but the more air the easer it
is to turn the crakes but the more you bounce. The tour riders run
160-190psi.

I'd be very, very surprised if even one rider in the entire
international road racing peloton used pressure that high. Track
racers on the velodrome are known to do so, but on the road the energy
lost to slamming and vibrating the rider can far exceed any reduction
in rolling resistance achieved by using very high tire pressure. Many
Tour de France riders still use sewup tires, one of whose major
advantages is the ability to run _lower_ pressures without pinch
flatting.

Chalo

"Chalo" wrote in message
...
"Burr" wrote:

If you are real light you can run less air but the more air the easer
it
is to turn the crakes but the more you bounce. The tour riders run
160-190psi.

I'd be very, very surprised if even one rider in the entire
international road racing peloton used pressure that high. Track
racers on the velodrome are known to do so, but on the road the energy
lost to slamming and vibrating the rider can far exceed any reduction
in rolling resistance achieved by using very high tire pressure. Many
Tour de France riders still use sewup tires, one of whose major
advantages is the ability to run _lower_ pressures without pinch
flatting.

Chalo

I learned something. I "thought" I remembered reading about them running
very high pressure.

Burr

Burr who? wrote:

If you are real light you can run less air but the more air the
easer it is to turn the crakes but the more you bounce. The tour
riders run 160-190psi.

I'd be very, very surprised if even one rider in the entire
international road racing peloton used pressure that high. Track
racers on the velodrome are known to do so, but on the road the
energy lost to slamming and vibrating the rider can far exceed any
reduction in rolling resistance achieved by using very high tire
pressure. Many Tour de France riders still use sewup tires, one of
whose major advantages is the ability to run _lower_ pressures
without pinch flatting.

Not true. The term "snake bite" pinch flat was coined over patching of
such flats in latex tube Clement tubulars. The term was important
because it was not generally known that a pinch flat causes two holes
(as pinching one's cheek with thumb and forefinger).

I learned something. I "thought" I remembered reading about them
running very high pressure.

Its easy to find all sorts of myth an lore about bicycle racers that
can "leap tall buildings in a single bound"

http://www.answerbag.com/q_view/110331

Men of steel whose tires are equally hard and fast. Drugs play no
role in any of that aura. Don't believe everything you hear about
bicycle racers methods and abilities.

Jobst Brandt

Pat wrote:
My pre-ride check consists of me squeezing the tire between thumb and
forefinger....



I do that too. But, I also like to give my wheels a spin and see if they
are running true and look for any bulges in the tires. It only takes a few
seconds.


Paul D Oosterhout


Okay, that's good---but I am NOT going to check my tires' air pressure every
single dang day! That's being obsessive about it. So what if the air
pressure has gone down 2 psi? or even, gasp, 5 psi?

Pat in TX



Of course, when you depress the presta stem, you are going to let out
some more air anyhow, but for me, topping the tires off doesn't take
long and the tires feel the same every day.