road bike tyre pressures

ThriceNightly · 27 Jul 2008 at 21:15

any idea what ball park tyre pressures are for this bike

scott speedster

i weigh 11 stone if that has any bearing

badbob · 27 Jul 2008 at 21:17

Look on the tyre sidewall. But usually 100 psi. That's if your pump is accurate.

fatherdougal · 27 Jul 2008 at 21:21

110-120psi? What width are your tyres?

badbob · 27 Jul 2008 at 21:28

What has width got to do with it?

fatherdougal · 27 Jul 2008 at 21:45

badbob said:
What has width got to do with it?

http://www.ctc.org.uk/DesktopDefault.aspx?TabID=3802

Rolling resistance, weight and tyre width all play a factor.
(£30 Assos Shorts £500 Ultegra bike?)

PhilthyPhil · 27 Jul 2008 at 21:48

Check the side of the tyre, it should say the max and min pressures. Do bear in mind that at your weight you probably do not want to use the max pressure. You will find that with the poor quality of our roads that high pressure tyres will give a very uncomfortable ride and you will get tired much quicker.

badbob said:
What has width got to do with it?

The tyre is always under the same load (your weight) regardless of width. So if you use a narrower tyre you need a higher pressure because that load is being transferred through a smaller contact area.

ThriceNightly · 27 Jul 2008 at 22:27

thanks for replies

tyres are continental ultrasport 700 X 23c (23-622)

says max 125psi

shall i start at say 110psi in front and rear?

should it be equal pressures front and rear?

badbob · 27 Jul 2008 at 22:29

You usually have front tyre a bit softer since most of your weight is on the back. 100 psi front and back should be ok.

fatherdougal · 27 Jul 2008 at 22:36

badbob said:
You usually have front tyre a bit softer since most of your weight is on the back. 100 psi front and back should be ok.

So then you have them the same?

I think that Specialized did a trial a while ago, according to my LBS, that found that optimum pressure in the UK on a 23 tyre was around 110. This compared to a continental optimum of 120. This was because of the generally worse road surface conditions in the UK. (or my LBS could have been blowing smoke up my arse)

badbob · 27 Jul 2008 at 22:38

Either way depending on how I want the ride

fatherdougal · 27 Jul 2008 at 22:48

badbob said:
Either way depending on how I want the ride

But you said that he should ride with the front slightly softer, at 100PSI on both??? :rolleyes:

ThriceNightly · 27 Jul 2008 at 22:53

once again thanks for the advice

my car pump doesn't appear too fit the valve as it's too small and my cycle pump does not have a gauge on it & is also a bit fiddly to operate.

i see myself buying another pump and guage which fits (any recomendations?)

Jonny ///M · 27 Jul 2008 at 23:10

ThriceNightly said:
once again thanks for the advice

my car pump doesn't appear too fit the valve as it's too small and my cycle pump does not have a gauge on it & is also a bit fiddly to operate.

i see myself buying another pump and guage which fits (any recomendations?)

Joeblow track pump for the win. Pumping things up to 120psi quite easily.

badbob · 27 Jul 2008 at 23:14

fatherdougal said:
But you said that he should ride with the front slightly softer, at 100PSI on both???

Around 100psi upto recommended pressure, maybe with the front one a bit lower. Really not set in stone :rolleyes:

fatherdougal · 27 Jul 2008 at 23:23

badbob said:
Around 100psi upto recommended pressure, maybe with the front one a bit lower. Really not set in stone

Perhaps it's just me. But you shouldn't offer advice if you don't know what you are talking about? I'm sure that you mean well and all.

badbob · 27 Jul 2008 at 23:33

Seems you're a smart arse. I know what I mean, perhaps I didn't phrase it properly. But basicall stick to recommended tyre pressure, or under that but not too low ie 100/95, and if you pump rear to certain tyre pressue then maybe set the front a bit lower, or same if you want. Like I said it's hardly rocket science, just follow the recommended tyre pressures, if you paid attention that's what I said in my first post.

Sheldon Brown has wrote about having the front lower.

fatherdougal · 27 Jul 2008 at 23:45

badbob said:
Seems you're a smart arse. I know what I mean, perhaps I didn't phrase it properly. But basicall stick to recommended tyre pressure, or under that but not too low ie 100/95, and if you pump rear to certain tyre pressue then maybe set the front a bit lower, or same if you want. Like I said it's hardly rocket science, just follow the recommended tyre pressures, if you paid attention that's what I said in my first post.

Sheldon Brown has wrote about having the front lower.

Yes but you are offering advice so you need to phrase it properly. "Look on the tyre sidewall. But usually 100 psi. That's if your pump is accurate", is what your first post actually said. This doesn't consider any of the other variables that are relative to the correct pressure.

Perhaps you mean, "What has width got to do with it?" ?

Quite a bit actually.

Perhaps I am being a "smart arse" but that is better than a bad boy dumb arse.

badbob · 27 Jul 2008 at 23:49

Perhaps you mean, "What has width got to do with it?" ?

Quite a bit actually.

The correct pressure, as a starting point is upto recommended tyre wall pressue, which is fairly obvious.

As for width relative to tyre pressure, my tourer tyres are rated to 115 psi, road bike 105 psi. So by your own reasoning, the tourer tyres should be lower because they're wider, but nooo..

Prat.

Jonny ///M · 28 Jul 2008 at 02:18

Tut tut you damn rroadies. I think badbob means......put it to whats ont he sidewall but to get a better(comfier) ride maybe put less in the front. The tyre company take the width into considerationg when they state the recomended pressure so you don't have to sit down and do maths arguing over the internet.

Generally with 23-25c tyres its between 100-120psi.

JBuk · 28 Jul 2008 at 05:24

fatherdougal said:
Perhaps you mean, "What has width got to do with it?" ?

Quite a bit actually.

Perhaps I am being a "smart arse" but that is better than a bad boy dumb arse.

whats your problem? what badbobs saying is correct and not hard to understand yet you just seem to be picking at him then insult the guy?? personnal attacks are not allowed by the way

tyre width has nothing to do with it aslong as you follow the min/max psi on the wall then it doesnt matter about the width

i always set mine to just under the recommended max psi on both