How hard should I pump road tyres?

worb68

Hi, complete newbie to road riding. Silly question but how hard should I pump my tyres up to?

Also what lube should I use on the chain - any specific road chain lube or can I use the same one as I do on my MTB?

Many Thanks.

slowbike

Depends on what tyres, what size they are and how much you weigh. Then there's the weather/condition variation.

Ranges seem to go from 80-120psi for 25 & 23mm tyres.

If you've got 23mm tyres I'd go for 100psi to start with. 25mm then 90psi should be ok - but check the limit on the sidewall.

kajjal

Mountain bike lube will be fine.

Tyre pressure is really anything from too low so you get poor control / a lot of punctures up to too high where you get a lot of road vibration. Check the tyre walls for the recommended range. I weight 15 st 7 and my 23mm tyres are both at 105psi.

diamonddog

Minimum tyre pressure on one of my bikes with 25mm tyres is 7bar/102.9psi which is way too high for my body weight (51kg) :shock:

simon_masterson

Ignore the fudge numbers on the tyre. Find a chart and match your weight to your tyre size.

Also, your chain lube should be fine.

Initialised

Simon Masterson wrote:

Ignore the fudge numbers on the tyre. Find a chart and match your weight to your tyre size.

Also, your chain lube should be fine.

Insert numbers here

http://www.dorkypantsr.us/bike-tire-pre ... lator.html

follow results.

Chain lube is chain lube, but us dedicated velocopedestrians wax.

holiver

90-100 PSI has worked fine for me on both 23mm and 25mm tyres on my Kinesis, even carrying loads of books and laptop or a week's worth of shopping.

BrandonA

Simon Masterson wrote:

Ignore the fudge numbers on the tyre. Find a chart and match your weight to your tyre size.

Also, your chain lube should be fine.

Ignore the charts and go for whatever feels comfortable for you. I'd stay within the recommendations of the wheels and tyres but where you go within this range is up to you. Personally I like a higher pressure even though it makes the ride slightly more "bumpy", you might value comfort more and want a lower pressure.

What I really hate is when you stand up to pedal and you are bouncing up and down because the pressure in the front tyre is too low.

rafletcher

diamonddog wrote:

Minimum tyre pressure on one of my bikes with 25mm tyres is 7bar/102.9psi which is way too high for my body weight (51kg) :shock:

Why is that? On the recent Prudential London race, I heard one of the commentators say that the tyres (for a wet race) were at 7.2 bar which is 104.4 psi, and I'm sure there would be pros your weight or close.

diamonddog

rafletcher wrote:

diamonddog wrote:

Minimum tyre pressure on one of my bikes with 25mm tyres is 7bar/102.9psi which is way too high for my body weight (51kg) :shock:

Why is that? On the recent Prudential London race, I heard one of the commentators say that the tyres (for a wet race) were at 7.2 bar which is 104.4 psi, and I'm sure there would be pros your weight or close.

I run my 23mm at a lower pressure than this so any possible gains re comfort are negated, it doesn't relate to any figures for tyre pressures/rider weight I have seen also I am not a pro.

simon_masterson

rafletcher wrote:

diamonddog wrote:

Minimum tyre pressure on one of my bikes with 25mm tyres is 7bar/102.9psi which is way too high for my body weight (51kg) :shock:

Why is that? On the recent Prudential London race, I heard one of the commentators say that the tyres (for a wet race) were at 7.2 bar which is 104.4 psi, and I'm sure there would be pros your weight or close.

They're running tubs, not clinchers.

BLW

I must be the black sheep of the family here, either that or just stupid...probably the latter.

I'm a roady and a MTB'r and don't have a doggy blue what pressure they are, that said, I do have a tyre pressure obsession (say's the OH) as I'm constantly checking and pumping!

I run my MTB harder when using it on the roads, not too hard but just so you can give a it little squeeze with a lot of force, then I let some air out when I'm on the trails, so there quite squeezable but not enough to make it hard work or to get any puntures due to running the too low.

As for the road bike, I like them hard but so they will give if I give it a hard nip with thumb and finger.

Sorry that was about as much use as a chocolate teapot, but I think sometimes people get carried away with numbers, if you can get used to judging what they should feel like, depending on the bike, your weight and what your doing on the bike, then you won't go far wrong.

rafletcher

Simon Masterson wrote:

rafletcher wrote:

diamonddog wrote:

Minimum tyre pressure on one of my bikes with 25mm tyres is 7bar/102.9psi which is way too high for my body weight (51kg) :shock:

Why is that? On the recent Prudential London race, I heard one of the commentators say that the tyres (for a wet race) were at 7.2 bar which is 104.4 psi, and I'm sure there would be pros your weight or close.

They're running tubs, not clinchers.

So? The pressure is the same isn't it (the post I quoted has 7 bar as the minimum on the tyre). Tubs may be more supple but not by that much over a good clincher.

simon_masterson

rafletcher wrote:

Simon Masterson wrote:

rafletcher wrote:

diamonddog wrote:

Minimum tyre pressure on one of my bikes with 25mm tyres is 7bar/102.9psi which is way too high for my body weight (51kg) :shock:

Why is that? On the recent Prudential London race, I heard one of the commentators say that the tyres (for a wet race) were at 7.2 bar which is 104.4 psi, and I'm sure there would be pros your weight or close.

They're running tubs, not clinchers.

So? The pressure is the same isn't it (the post I quoted has 7 bar as the minimum on the tyre). Tubs may be more supple but not by that much over a good clincher.

That's just it - it's not the same. Tubs are generally inflated a bit higher, and can take much more than you'd ever use with clinchers.

ai_1

These "What pressure should I use?" questions crop up constantly and always get such a broad spectrum of answers as to be essentially useless. It seems pretty clear that there are some pre-conceptions so widely held as to be considered fact by most and there are a few basic principles that don't seem to be widely understood at all. Then there is the fact that different riders will have different priorities and different preferences. The priorities should guide the use of objective data but the preferences may overule the outcome. For example, if a rider likes the feel of hard tyres and hates any give when, say, sprinting, then regardless of the optimum pressure for rolling resistance, comfort, grip, etc, they will probably end up using high pressures.

Anyway. Is it worth trying to find a consensus on the following?

Preconception #1: Higher pressure is faster...... What's the rationale? Is this valid? What are the assumptions & exceptions?
Preconception #2: Lower pressure is more comfy...... Under what conditions? Is this dependent on other factors? e.g. tyre size
Preconception #3: Bigger tyre is more comfortable....... Under what conditions? Is this dependent on other factors? e.g. tyre pressure
Preconception #4: Softer tyres will feel mushy...... Does this depend on the tyre type, size, other factors?

Basic principle #1: Higher pressure = lower contact area (This is simple physics: Area x Pressure = Force). As grip is largely dependent on contact area this means lower pressure is generally desirable for grip.
Basic principle #2: Front and rear tyres do not have the same operating conditions nor do they serve the same purpose. Therefore it makes no sense to expect the same pressure to be optimal for both. The rear in almost all cases takes the majority of the load. It also provides all the propulsion but usually the minority of the braking. The front tyre takes less weight but is critical to braking and handling, it's also much more critical that the front tyre does not skid.

BrandonA

Ai_1 wrote:

Basic principle #2: Front and rear tyres do not have the same operating conditions nor do they serve the same purpose. Therefore it makes no sense to expect the same pressure to be optimal for both. The rear in almost all cases takes the majority of the load. It also provides all the propulsion but usually the minority of the braking. The front tyre takes less weight but is critical to braking and handling, it's also much more critical that the front tyre does not skid.

I know a few people that don't like the tyres but I love the Mavic tyres. You get a different compound for the front and rear tyres. The front is designed for grip and the rear for power delivery.

ai_1

BrandonA wrote:

Ai_1 wrote:

Basic principle #2: Front and rear tyres do not have the same operating conditions nor do they serve the same purpose. Therefore it makes no sense to expect the same pressure to be optimal for both. The rear in almost all cases takes the majority of the load. It also provides all the propulsion but usually the minority of the braking. The front tyre takes less weight but is critical to braking and handling, it's also much more critical that the front tyre does not skid.

I know a few people that don't like the tyres but I love the Mavic tyres. You get a different compound for the front and rear tyres. The front is designed for grip and the rear for power delivery.

I'm using Yksion Pros myself at the moment and I like them. Not specifically for this reason (they came with the bike) but I agree there's merit in it. Continental's Force/Attack combo is the same idea I think.

simon_e

People often overcomplicate this subject, Michelin's pressure chart is a good place to start. If you want to experiment then try 10 psi either side of the recommended figure.

Dippydog2

Simon E wrote:

People often overcomplicate this subject, Michelin's pressure chart is a good place to start. If you want to experiment then try 10 psi either side of the recommended figure.

It's an interesting chart, but I cannot see the scientific reason for the straight lines at the ends of the scales. Is this a case of a minimum and a maximum the tyre can deal with and therefore anyone outside that weight scale has to compromise?

And, what about differences in weight between the front and rear wheels?

JayKosta

Front tire should be at high enough pressure so that no (or very little) tire 'bulging' is visible when riding.
Rear tire should be high enough pressure so that just a little bulging is visible.

If pressure is too low the tires will feel 'squirmy' - as if you are riding on sand.
Too high pressure will give a very rough ride.

Jay Kosta
Endwell NY USA

ai_1

JayKosta wrote:

Front tire should be at high enough pressure so that no (or very little) tire 'bulging' is visible when riding.
Rear tire should be high enough pressure so that just a little bulging is visible.

If pressure is too low the tires will feel 'squirmy' - as if you are riding on sand.
Too high pressure will give a very rough ride.

Jay Kosta
Endwell NY USA

That depends very much on the size and shape of tyre you're using. A 25mm tyre run relatively soft may well have an obvious bulge but be perfectly acceptable. Is there a technical reasoning behind your advice or is it just a rule of thumb that gives you results you're happy with?

simon_e

Dippydog2 wrote:

It's an interesting chart, but I cannot see the scientific reason for the straight lines at the ends of the scales. Is this a case of a minimum and a maximum the tyre can deal with and therefore anyone outside that weight scale has to compromise?

And, what about differences in weight between the front and rear wheels?

Relax, it's a recommendation not a Physics exam!

Re: front & rear, like I said, you are allowed to experiment if you want to - there's no 'Tyre Pressure Police' (except on this forum, it seems ). I don't understand why people make such a simple thing so complicated.

ai_1

Simon E wrote:

Dippydog2 wrote:

It's an interesting chart, but I cannot see the scientific reason for the straight lines at the ends of the scales. Is this a case of a minimum and a maximum the tyre can deal with and therefore anyone outside that weight scale has to compromise?

And, what about differences in weight between the front and rear wheels?

Relax, it's a recommendation not a Physics exam!

Re: front & rear, like I said, you are allowed to experiment if you want to - there's no 'Tyre Pressure Police' (except on this forum, it seems ). I don't understand why people make such a simple thing so complicated.

Silly and irritating comments Simon!
Its a discussion about tyre pressure and you're making fun of those discussing tyre pressure. No-one is policing, no-one is overcomplicating. Simple version = soft enough to provide some comfort but hard enough to avoid regular pinch puntures. That doesn't mean anyone who says more should be ridiculed.

drlodge

I pump up my Vittoria Open Pave 24c normally to around 110 rear and 105 front. Had them a little lower yesterday (105/95)doing Tour Of The Hills and it did feel a little more comfy.

simon_e

Ai_1 wrote:

Silly and irritating comments Simon!

Not silly, just expressing a different PoV in a light-hearted manner. I just feel this is not the serious, complicated topic some people are trying to make it, and your put-downs won't change that.

You don't have to be irritated by a difference of opinion, that's your choice.

JayKosta

Ai_1 wrote:

...
That depends very much on the size and shape of tyre you're using. A 25mm tyre run relatively soft may well have an obvious bulge but be perfectly acceptable. Is there a technical reasoning behind your advice or is it just a rule of thumb that gives you results you're happy with?

===========
Just my rule of thumb for riding on paved roads.

Jay Kosta
Endwell NY USA