# Schwalbe Marathon/Marathon Plus de facto PSI



## Zenroad (13 Dec 2012)

I'm about to shift allgiance (I think) from Continental to Schwalbe, and I'm curious about ACTUAL psi for the Marathon or the Marathon Plus, 26 x 1.75. The rating is 45-70psi. Is anyone running these tires above that?

My old Continental Travel Contacts (26 x 1.75) are rated at max 80psi, but I consistently run them at 90 without a problem.

Is anyone inflating the Marathon (or Plus) to 80 or 85?


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## Stonepark (13 Dec 2012)

Running marathon plus tours and marathon winters at 90 psi on rear and 45psi on the front, if you are looking for a commuting tyre, use a narrower tyre.

Both about 1.5 inch, tyre safety pressures are usually under twice the maximum the tyre can take, so you should be ok.


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## Zenroad (13 Dec 2012)

Thanks, Stonepark. Yeah, I know that tire ratings are usually well under the real safety limit. 

As for width, 1.75 is as narrow as I want to go. I know that Schwalbes are tough, so I hope that 85psi is not pushing it too close to the limit. These will be for 95% on-road usage.


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## willem (14 Dec 2012)

Why would you want to inflate a tyre this much? It will negate all advantages of Mr Dunlop's wonderful invention. A much better strategy would be to use a more flexible tyre at lower pressures. That way you are far more comfortable, and significantly faster on any road surface other than a poole table. A 50 mm Schwalbe Big Apple at reduced pressure would be a much better choice, and more than sturdy enough. In winter, use the Conti Topcontact Winter II.
Willem


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## hoopdriver (14 Dec 2012)

Yes, there is no point in running them that high. It's silly. I run mine at about sixty five psi on my winter bike, which gives a nice blend of rolling and comfort.


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## BigonaBianchi (15 Dec 2012)

I just rode schwalbe marathon plus 28's across america at 100psi ..no flats at all and roll beautifully.


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## SpokeyDokey (16 Dec 2012)

32mm Marathon Supremes 90psi front and rear.


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## hoopdriver (16 Dec 2012)

Those aren't 26" tyres. I thought the OP was referring to 26" tyres. If they are 700c I too would run higher pressures, but for the 26" M+ on my winter bike I definitely keep to 65-70psi.


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## ankaradan (17 Dec 2012)

Zenroad said:


> I'm about to shift allgiance (I think) from Continental to Schwalbe, and I'm curious about ACTUAL psi for the Marathon or the Marathon Plus, 26 x 1.75. The rating is 45-70psi. Is anyone running these tires above that?
> 
> My old Continental Travel Contacts (26 x 1.75) are rated at max 80psi, but I consistently run them at 90 without a problem.
> 
> Is anyone inflating the Marathon (or Plus) to 80 or 85?


 
Can I ask why?

I'm in the process of stripping large knobbly tyres of an old MTB, to use it on road/tracks. I'm looking at various Schwalbe and Continental tyres, and unsure what to go for


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## Jimmy Doug (17 Dec 2012)

I run mine at about 6 bar (85 psi). Never had a puncture in 6000 kms. I wouldn't go above this, however.


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## Bodhbh (17 Dec 2012)

Is there an issue with blowing rims when running large volume tyres at such high pressures? Not a rhetorical question, just wondered.


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## robgul (17 Dec 2012)

Bodhbh said:


> Is there an issue with blowing rims when running large volume tyres at such high pressures? Not a rhetorical question, just wondered.


 
... unless rims are knackered I would suggest it's highly unlikely

My 2p on pressures - I run every bike I have at 10 or 12% above the max it says on the tyre-wall ... better rolling, fewer flats .. and the ride isn't really affected in terms of comfort. (That's from 23mm on my fixed to 32mm on the tourer)

Rob


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## Crankarm (18 Dec 2012)

There might be a wide margin above which you can inflate the tyre but as Bod suggests think of the rim as well. A new rim might not be so much of a problem but a not so new one might fail even quicker than it might have. Might only apply to rim braked rims although disc rims can fail as well, although unlikely.

I inflate my Marathons and Specialised Nimbus' to max rating on side of tyre.


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## willem (18 Dec 2012)

Running wide tyres at high pressures can easily blow up your rims, and you could get badly hurt. I cannot now retrieve the sums I once saw, but blowing up a rim is easier than you may think. As for the benefits of high pressures, there are very few. High pressures increases (yes) the risk of punctures because the tyre is pressed onto the debris rather than gently fold over it. For the same reason, because wide tyres can be run at lower pressures, you will have fewer punctures from road debris the wider the tyre (and as long as you avoid snake bites). Finally, on real roads rolling resistance does not decrease with higher pressures. On the contrary, because a wheel with wide tyres and low pressures rolls more smoothly over an uneven surface. Ultra stiff tyres like Marathon Plusses are a partial exception to this, because they will not flex much even with lower pressures. They are always slow (and uncomfortable).
Willem


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## snailracer (18 Dec 2012)

willem said:


> ...on real roads rolling resistance does not decrease with higher pressures. On the contrary, because a wheel with wide tyres and low pressures rolls more smoothly over an uneven surface...


+1

Inflating tyres harder will transmit more vibration to the rider's body/luggage, which jiggle more (so-called "suspension losses") and dissipate more power i.e. slower.

Running tyres that are too soft increases friction/deformation losses within the tyre, which also wastes power and is well-known as classic "rolling resistance".

It turns out (or, rather, tyres are designed that way) that power losses from both these effects are of similar magnitude for real-life roads and practical tyre pressures, and so there is a pressure sweet spot where the combined power losses from both phenomena are minimised. Empirical testing by some sources suggest that the sweet spot pressure is where the tyre drop of the loaded wheel is 15%:

http://www.dorkypantsr.us/bike-tire-pressure-calculator.html

http://www.bikequarterly.com/images/TireDrop.pdf

Note that the optimal pressure varies a lot with wheel load, which may be very different between different riders and front/rear, so one would have to find out the weight on each wheel using scales while sitting on the bike.

For smoother roads, a higher pressure will be faster, and vice-versa for rougher roads. However, as road roughness is hard to quantify, it is better (from a speed point of view) to err too low than too high, because suspension losses increase much more sharply (per PSI of over-inflation) than rolling resistance losses do (per PSI of under-inflation).



willem said:


> ...Ultra stiff tyres like Marathon Plusses are a partial exception to this, because they will not flex much even with lower pressures. They are always slow (and uncomfortable).
> Willem


While I do not discount your theory about stiff tyres being less comfortable, I am not convinced that even a super-stiff tyre is stiff enough to transmit much more vibration than a more flexible tyre. One possible confounding factor is that MP's and similar utility tyres tend only to be available in the larger sizes - it is often not possible to inflate them to low-enough pressure to give a 15% tyre drop, so they tend to be over-inflated and therefore uncomfortable.

For example, I would have to inflate my front 1.75" MP tyre to only 30 psi to carry the 30kg load on my front wheel - this would conflict with Schwalbe's instructions, which mandate they be pumped to at least 45psi to keep them secure on the rim. The result is, I pump them to 45psi and accept the extra discomfort.


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## Crankarm (18 Dec 2012)

.


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## CopperBrompton (20 Dec 2012)

Willem's post is contradicted by every article ever posted by a tyre manufacturer ...

Lower pressures = greater puncture risk. Within the manufacturer recommended range, lower pressures will be more comfortable, higher pressures will have reduced rolling resistance. The optimum pressure will vary by rider, both in terms of weight and personal susceptibility to vibration. For me, the optimum is a wide tyre inflated to the maximum recommended pressure.


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## snailracer (21 Dec 2012)

Trikeman said:


> Willem's post is contradicted by every article ever posted by a tyre manufacturer ...
> 
> Lower pressures = greater puncture risk. Within the manufacturer recommended range, lower pressures will be more comfortable, higher pressures will have reduced rolling resistance. The optimum pressure will vary by rider, both in terms of weight and personal susceptibility to vibration. For me, the optimum is a wide tyre inflated to the maximum recommended pressure.


I take it that you do not believe in suspension losses?


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## CopperBrompton (21 Dec 2012)

snailracer said:


> I take it that you do not believe in suspension losses?


 
You do? Why so?


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## sabian92 (22 Dec 2012)

I run 25x700c Marathon+ at 115psi, just to throw that out there. I'm a heavy guy though, 15 and a half stone.


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## snailracer (23 Dec 2012)

Trikeman said:


> You do? Why so?


Have you ever noticed that you slow down when riding over heavily-textured tarmac roads? That's mostly due to suspension losses.

Suspension losses describe the energy wasted in the rider's body (& luggage) as it jiggles in response to vibration transmitted to it due to the roughness of the road. Energy is lost as heat, by the same viscous, frictional and elastic mechanisms that take place in car shock absorbers.

I don't think it's tenable to deny that suspension loss exists, the only question is whether they are significant enough to be noticeable in comparison to other bike/tyre losses. These folks persuaded me that they are:
http://janheine.wordpress.com/2010/10/18/science-and-bicycles-1-tires-and-pressure/

Suspension losses are not the same thing as losses due to classic "rolling resistance", which are due to frictional and deformation losses that happen within the tyre itself. Sometimes both suspension losses and classic rolling resistance are lumped together as "rolling resistance", but that is just layman's imprecise use of the terminology.

Tyre manufacturers measure classic "rolling resistance" by running tyres on a smooth steel drum, which unquestionably reduces as tyre pressure is increased. However, real roads are not as smooth as the steel drum, and suspension losses increase as tyre pressure increases (i.e. the rider jiggles more), even as losses due to classic rolling resistance reduce.

Tyre manufacturers fully understand suspension losses. I can only suggest the following reasons why they don't talk about it:

It's too complicated to explain and they risk annoying customers who don't understand their explanation
Trade secrets
It shows that there is a point beyond which the tyre itself doesn't matter much - which doesn't help sell expensive, high-end tyres
They can't (or won't) agree a standard with other tyre manufacturers over how rough a "real" road or how lossy a rider's jiggling body should be.
Tyres used in velodromes (i.e. smooth surface) are often inflated to over 200psi. However, nobody uses such high pressures on the road, even for short time-trial racing, because they'd be slower, even if they don't fully understand why.

The concept of suspension loss is well-established in highway engineering circles, as it has direct impact on the fuel consumption of vehicles using roads.


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## CopperBrompton (23 Dec 2012)

You misunderstand. You said: 
_I take it that you do not believe in suspension losses?_​and I asked why you would make that odd assumption?


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## snailracer (23 Dec 2012)

Trikeman said:


> You misunderstand. You said:
> _I take it that you do not believe in suspension losses?_​and I asked why you would make that odd assumption?


Reading your post again, I think I did misunderstand, apologies.


Trikeman said:


> Lower pressures = greater puncture risk. Within the manufacturer recommended range, lower pressures will be more comfortable, higher pressures will have reduced rolling resistance. The optimum pressure will vary by rider, both in terms of weight and personal susceptibility to vibration. For me, the optimum is a wide tyre inflated to the maximum recommended pressure.


Your post suggests that running at a pressure less than the maximum simply results in more resistance - that is what I disagree with, as it does not account for reduced suspension loss, which affects the overall resistance.


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## CopperBrompton (23 Dec 2012)

Mostly I was taking issue with the puncture risk, but on typical road surfaces somewhere close to the maximum pressure will be fastest. I agree things will be different on a very rough surface.


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## MacB (24 Dec 2012)

I've read lots of the studies, articles and opinion pieces and would immediately argue that Willem does not contradict everyone out there, far from it actually especially in terms of touring.

But I've given up arguing the toss about this sort of stuff, all I can say is that my own experience has led me to adopt the sort of approach Willem advocates. Loads of factors go into this personal decision but wider and softer is the way I like to roll, personally and on a bike 

What I can say for a fact is that the fear of pinch punctures etc is vastly overstated, to the point at which I wonder what it is based on. For most of my miles I've been over 15 stone and a lot have been done between 17 and 19 stone, both with and without luggage. I've never gone above 100psi even with a 23mm tyre and had no problems with punctures.

Quite how someone weighing in about the same as my left leg can claim they need over 100psi to avoid pinch punctures. Either it's nonsense or they have no road sense and ability to avoid crazy potholes.


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## CopperBrompton (24 Dec 2012)

Pinch punctures should be rare with any sensible pressure, but conventional punctures are more likely at lower pressures.


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## Crankarm (25 Dec 2012)

MacB said:


> I've read lots of the studies, articles and opinion pieces and would immediately argue that Willem does not contradict everyone out there, far from it actually especially in terms of touring.
> 
> But I've given up arguing the toss about this sort of stuff, all I can say is that my own experience has led me to adopt the sort of approach Willem advocates. Loads of factors go into this personal decision but wider and softer is the way I like to roll, personally and on a bike
> 
> ...


 
It's not tyres or even tyre pressures that is the problem for these cyclists, but eye sight. Should have gone to SpecSavers comes to mind.


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## ChrisBailey (26 Dec 2012)

Zenroad said:


> I'm about to shift allgiance (I think) from Continental to Schwalbe, and I'm curious about ACTUAL psi for the Marathon or the Marathon Plus, 26 x 1.75. The rating is 45-70psi. Is anyone running these tires above that?
> 
> My old Continental Travel Contacts (26 x 1.75) are rated at max 80psi, but I consistently run them at 90 without a problem.
> 
> Is anyone inflating the Marathon (or Plus) to 80 or 85?


 
My commute is either 12 or 15 miles depending upon route, the 15 miles route was almost always faster as it contains much more continual cycling, less give ways, roundabouts, traffic lights etc. Then I switched from my Marathon plus's (Crazyguy has its own equivalent of helmet/mudguard flame wars on these tires) to Marathon Racers, not lightweight but ~50% of the weight of the Plus's and the time on the different commutes is almost identical. The effort to get those brutes (the plus's) turning is a significant factor. I run all my tires at the top end of the manufacturer's guidance FWIW.

I think I understand the argument related to rolling resistance and tire width, but tire weight is very noticeable. I will not commute on plus's again as the puncture rate for me has always been minimal, maybe 1 a year, seemingly irrespective of brand, and as to touring (this forum) I never have and never will.

Not sure how off topic this response is, but if the question of the OP is ultimately what is most efficient tire to ride given the associated width/pressure/weight/puncture concerns then my vote for touring is to veer from the tire pressure to tire weight, think Durano, Duraskin or Armadillo, for cummuting if the puncture issue is more significant, marathons or marathon racers, but I would only go plus's if the ride is extreme, along glass strewn paths or similar.

Chris


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## CopperBrompton (27 Dec 2012)

Marathon Plus versus a lighter tyre for me comes down to two questions:
1. How much hassle is a puncture for you?
2. How much of your cycling is start-stop versus cruising?

The first is obvious. Personally, I'm a mechanical illiterate and changing a tube on the rear tyre would take me about a fortnight and result in the deaths of several innocent bystanders. If you can change a wheel in less than ten seconds by the power of thought, your priorities will be different.

The second is less obvious. A heavier tyre takes more effort to accelerate, but once at cruising speed, it actually helps maintain your momentum better than a lighter tyre (think about how a flywheel works). So for lots of stop-start riding, a heavy tyre penalises you, while on a cruising ride, a heavier tyre assists you.


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