Tyre pressures

On my road bike :-

Front - 80 psi, Rear - 120 psi. (On the previous rear tyre I had, I
could go to 145psi but this new tyre only goes to 120psi)

What tyre pressures do others use on their road bikes?

I would also be curious to know the rationale for your choices to see if
it syncs with mine.

I use 120 front and rear ( or them Max rated pressure for the tire)

Lower rolling resistance and at this pressure I seem to get less
flats.

Depending on the rim construction you need to pay careful attention to
the rim tape as the pressures go up, as I have seen tubes blow out
into the holes used to access the spoke nipples on deep walled rims.

Luckily this happened while the bike was in the sun on a bike rack on
the back of the car, and another time while locked in the bike shed at
work in the middle of summer.


On Tue, 08 Mar 2011 16:46:29 +1100, Geoff Lock glock@home wrote:

On my road bike :-

Front - 80 psi, Rear - 120 psi. (On the previous rear tyre I had, I
could go to 145psi but this new tyre only goes to 120psi)

What tyre pressures do others use on their road bikes?

I would also be curious to know the rationale for your choices to see if
it syncs with mine.

On 2011-03-08, noemail@nowhere noemail@nowhere wrote:
I use 120 front and rear ( or them Max rated pressure for the tire)
...
On Tue, 08 Mar 2011 16:46:29 +1100, Geoff Lock glock@home wrote:

Front - 80 psi, Rear - 120 psi. (On the previous rear tyre I had, I
could go to 145psi but this new tyre only goes to 120psi)
...

45 in the front, 65 in the rear. 700Cx32 tyres. I put a bit more in
the rear tyres if I have a heavy load in the panniers.

If that sounds too low, read this:
http://www.bikequarterly.com/images/TireDrop.pdf

I used to inflate my tyres to over 100psi till I read this and other
articles. Now I get a much more comfortable ride for no discernable
difference in rolling resistance. The number of punctures has fallen
too. Initially I worried about pinch flats, but I haven't had any of
those at all.

--
John
Is that the truth, or is your News Limited?

noemail@nowhere wrote:
I use 120 front and rear ( or them Max rated pressure for the tire)

Lower rolling resistance and at this pressure I seem to get less
flats.

Depending on the rim construction you need to pay careful attention to
the rim tape as the pressures go up, as I have seen tubes blow out
into the holes used to access the spoke nipples on deep walled rims.

Luckily this happened while the bike was in the sun on a bike rack on
the back of the car, and another time while locked in the bike shed at
work in the middle of summer.

Agree. Unlike car tyres, there is no argument against maximum rated pressure.

Absolutely no argument.

Rim tape issue reminds me of a story.

T.

On Tue, 08 Mar 2011 16:46:29 +1100, Geoff Lock glock@home wrote:

On my road bike :-

Front - 80 psi, Rear - 120 psi. (On the previous rear tyre I had, I
could go to 145psi but this new tyre only goes to 120psi)

What tyre pressures do others use on their road bikes?

I would also be curious to know the rationale for your choices to see if
it syncs with mine.

On 8/03/2011 8:42 PM, noemail@nowhere wrote:
I use 120 front and rear ( or them Max rated pressure for the tire)

Lower rolling resistance and at this pressure I seem to get less
flats.

I agree with the lower rolling resistance but I never tort about the flats.

Depending on the rim construction you need to pay careful attention to
the rim tape as the pressures go up, as I have seen tubes blow out
into the holes used to access the spoke nipples on deep walled rims.

Hm, that's a good point - never tort of that one either, although one
would probably have to significantly overinflate the inner tube to get
that to happen unless the rim tape is really crappy and paper thin.

On 8/03/2011 9:53 PM, John wrote:
On 2011-03-08, noemail@nowherenoemail@nowhere wrote:
I use 120 front and rear ( or them Max rated pressure for the tire)
...
On Tue, 08 Mar 2011 16:46:29 +1100, Geoff Lockglock@home wrote:

Front - 80 psi, Rear - 120 psi. (On the previous rear tyre I had, I
could go to 145psi but this new tyre only goes to 120psi)
...

45 in the front, 65 in the rear. 700Cx32 tyres. I put a bit more in
the rear tyres if I have a heavy load in the panniers.

If that sounds too low, read this:
http://www.bikequarterly.com/images/TireDrop.pdf

Thanks for the link to that very interesting article, John. Until I read
that article, I did think you were crazy to use such low pressures on
700Cx32 - my tyres are 700Cx23, you see.

15% tyre drop, eh? Hm, that is something new to me so it is definitely
something to think about.

I used to inflate my tyres to over 100psi till I read this and other
articles. Now I get a much more comfortable ride for no discernable
difference in rolling resistance. The number of punctures has fallen
too. Initially I worried about pinch flats, but I haven't had any of
those at all.

By pinch flats, you mean when the inner tube is pinched between the rim
and the tyre wall? If so, I don't think I have ever had one of those as
most of my flats have clearly been due to the inner tube been pierced by
something or other.

Also, it is interesting that you feel no real disadvantage in rolling
resistance despite the lower pressures. I must admit that after I fix a
rear wheel flat and use my little hand pump to get my tyre up, to say,
60psi (I am a bit of a weakling, I know), the subsequent ride does feel
a bit softer in the rear. I do understand this is a subjective matter.

On 8/03/2011 11:14 PM, Tomasso wrote:
noemail@nowhere wrote:
I use 120 front and rear ( or them Max rated pressure for the tire)

Lower rolling resistance and at this pressure I seem to get less
flats.

Depending on the rim construction you need to pay careful attention to
the rim tape as the pressures go up, as I have seen tubes blow out
into the holes used to access the spoke nipples on deep walled rims.

Luckily this happened while the bike was in the sun on a bike rack on
the back of the car, and another time while locked in the bike shed at
work in the middle of summer.

Agree. Unlike car tyres, there is no argument against maximum rated
pressure.

Absolutely no argument.

Rim tape issue reminds me of a story.

Alright, I bite Feel like telling us that story on rim tape?

"John" wrote in message
eb.com...
On 2011-03-08, noemail@nowhere noemail@nowhere wrote:
I use 120 front and rear ( or them Max rated pressure for the tire)
...
On Tue, 08 Mar 2011 16:46:29 +1100, Geoff Lock glock@home wrote:

Front - 80 psi, Rear - 120 psi. (On the previous rear tyre I had, I
could go to 145psi but this new tyre only goes to 120psi)
...

45 in the front, 65 in the rear. 700Cx32 tyres. I put a bit more in
the rear tyres if I have a heavy load in the panniers.

If that sounds too low, read this:
http://www.bikequarterly.com/images/TireDrop.pdf

I used to inflate my tyres to over 100psi till I read this and other
articles. Now I get a much more comfortable ride for no discernable
difference in rolling resistance. The number of punctures has fallen
too. Initially I worried about pinch flats, but I haven't had any of
those at all.

That makes sense but I always rode on 23mm tyres. This chart suggests that
at 110 my rear tyre may have been underinflated.

Theo

On 2011-03-08, Geoff Lock glock@home wrote:
On 8/03/2011 9:53 PM, John wrote:
45 in the front, 65 in the rear. 700Cx32 tyres. I put a bit more in
the rear tyres if I have a heavy load in the panniers.

If that sounds too low, read this:
http://www.bikequarterly.com/images/TireDrop.pdf

Thanks for the link to that very interesting article, John. Until I read
that article, I did think you were crazy to use such low pressures on
700Cx32 - my tyres are 700Cx23, you see.

15% tyre drop, eh? Hm, that is something new to me so it is definitely
something to think about.

The idea is to let the pneumatic tyre do its job, evening out the bumps
and giving you a smooth ride and maximum efficiency. If your tyres are
rock hard, you're wasting energy bouncing up and down. You may as well
have solid rubber tyres.


By pinch flats, you mean when the inner tube is pinched between the rim
and the tyre wall? If so, I don't think I have ever had one of those as
most of my flats have clearly been due to the inner tube been pierced by
something or other.

Yes. Also called a "snake bite" puncture, because you get two holes
close together where the tube has folded under the rim.


Also, it is interesting that you feel no real disadvantage in rolling
resistance despite the lower pressures. I must admit that after I fix a
rear wheel flat and use my little hand pump to get my tyre up, to say,
60psi (I am a bit of a weakling, I know), the subsequent ride does feel
a bit softer in the rear. I do understand this is a subjective matter.

After I started using lower pressure I noticed two things:

1) my commute times didn't get any longer (and I wasn't working any
harder)

2) the ride was more comfortable

Win-win, I'd say.

--
John
Having Fun Is Half The Fun. - Guru Adrian

On 2011-03-09, Theo Bekkers wrote:

That makes sense but I always rode on 23mm tyres. This chart suggests that
at 110 my rear tyre may have been underinflated.

As the article says, you still need quite high pressures in 23mm tyres.

It's not super-critical. I only check the pressure once a week, so I
overinflate by about 5psi. By the next week, the pressure might be a
few psi below the ideal. There's not a big difference in the ride.

--
John
Is that the truth, or is your News Limited?