32mm vs 25mm tyre on cyclocross bike for road use?

[MikeF]

I ride every where on 28mm Marathons on my road bike, up hill, down dale, on road, off road, forest and mountain tracks ..... tried 23, 25 and 32 mm tyres and came back to 28mm Marathons as the best of the bunch.

Marathons come in all sorts, so you need to say what type.

[landsurfer]

I ride every where on 28mm Marathons on my road bike, up hill, down dale, on road, off road, forest and mountain tracks ..... tried 23, 25 and 32 mm tyres and came back to 28mm Marathons as the best of the bunch.

Marathons come in all sorts, so you need to say what type.

28mm, new, with reflective side ... and tread and puncture stuff ,,, green something .... fitted by SPA.
Although they wanted to fit the 32mm version ...
My bikes are in Yorkshire and i'm currently trapped in deepest Essex so i can't nip outside and check.

Which is probably good as i'm the wrong side of a pint of fine English Ale and Cider.

[Mattievrs]

The Randonneur Pro are a much better tyre, the carcass is totally different to the non pro version (120tpi vs 60tpi).

It’s worse still: the non-Pro has a 30 TPI casing.

I have a set of unused 25mm Randonneur in the shed from a previous project that never happen so I think I’ll mount a tyre to see how it fits first.

That’s the same, slow tyre you’re using now, just in a narrower section. It may feel different (less comfortable), but it won’t be much faster. For easier rolling, you need a faster tyre. Comparable tyres vary by about a factor of two in rolling resistance.

What tyres do you use and what would you recommend?

[PH]

Load and pressure will have a major effect on the way a tyre behaves. There seems little point to me considering width without the others. It’s no surprise people come to different conclusions when they do.

Indeed, but tyre construction and tread also make a big difference. Hypers have quite a low rolling resistance at low pressures where other tyres would have noticeable drag. I gain the impression that the 35mm have a lower rolling resistance than 32mm ones, but it's just my impression.

Indeed, they are all linked. But my unscientific experience is that better construction in itself doesn't add much to comfort, but a lower pressure does and it's the better construction that allows that without loss of rolling resistance. Of course you still have to have enough pressure to keep the load off the road, however well constructed the tyre is.
I ride with someone who is not much more than half my weight, they're very happy to ride anywhere on 25mm tyres, when I'd prefer to have at least 32mm. If I were to ride 25s at the pressure they do I'd pinch flat before very long, or if I were to ride them at a pressure appropriate for my load I may as well dispense with pneumatics altogether.

[meic]

Yes, my daughter is riding around on 23mm tyres with 40-50psi in them.
That would guarantee two wrecked rims in one ride with me riding.

[Samuel D]

What tyres do you use and what would you recommend?

I use the old version (model number HS 448) of the Schwalbe One, except for the worst months of the winter when I prefer something with more grip.

Recommendations depend on how much you dislike punctures. Rolling resistance is caused by hysteresis (sluggish rebound after deformation) of the tyre materials. Speaking broadly, more material is more durable and puncture resistant, but more material also increases rolling resistance and reduces the comfort that pneumatic tyres can provide over rough surfaces.

Properly fast tyres include the various versions of the Vittoria Corsa, Continental Grand Prix 4000 S II, Schwalbe One, Specialized Turbo Cotton, Michelin Power Competition, etc. See the Bicycle Rolling Resistance website for more suggestions. Not all of these have great grip in the wet. These are considered ‘race’ tyres by some (though not serious racers!), but so what?

Tyres with more puncture resistance but still a great deal less rolling resistance than your present tyres include the Continental Grand Prix 4-Season, Michelin Power Endurance, Michelin Pro4 Endurance V2, and similar. These tend to do well in the wet and might be a good compromise for you.

But my suggestion is to try one of the high-end road tyres in my third paragraph, ideally at a width of about 28 mm. If you end up having too many punctures, then switch to a heavier tyre. Otherwise, how would you know whether a light tyre would be tough enough? I cycle in glass-strewn Paris and the puncture frequency is tolerable for me.

[Bmblbzzz]

When it comes to rolling resistance, the way the tyre is constructed matters a great deal more than the width.

This, definitely.

However, Vittoria Randonneur tyres have high rolling resistance,

This, through personal experience.

so almost any 25 mm tyre would roll more easily.

Therefore by inference this, but I'm sure there are some that 25s that roll badly.

The Vittoria Voyager Hyper would have something like half the rolling resistance despite being of similar width.

Staying with Vittoria, I can recommend Rubinos for low rolling resistance and good puncture resistance and grip. Other tyre manufacturers are available.

Also bear in mind Spinners' point about rim width.

[meic]

I can recommend Rubinos for low rolling resistance and good puncture resistance and grip.

These tyre manufacturers do make life difficult with their convoluted tyre names, did you mean Rubinos or Rubino Pros. I would agree with the latter, not so sure about the former.

[Bmblbzzz]

Sorry, I meant Rubino Pros. But AFAIA "Pro" is just Vittoria-speak for a folding tyre. I'm not aware of any other differences between the two. Whether that bead difference alone is enough to make a significant difference to rolling resistance, I don't know. It certainly makes them easier to fit!

[meic]

More to it than the folding.
The Pros also have much finer carcass fibres 150tpi v 60 tpi.

[andrew_s]

Recommendations depend on how much you dislike punctures. Rolling resistance is caused by hysteresis (sluggish rebound after deformation) of the tyre materials. Speaking broadly, more material is more durable and puncture resistant, but more material also increases rolling resistance and reduces the comfort that pneumatic tyres can provide over rough surfaces.

Whilst it's true that hysteresis is the cause of rolling resistance on a smooth surface, and that this is best addressed by high quality tyres, if the surface isn't smooth (and it doesn't have to be very rough), there are other sources of energy loss around, which can often be more important than hysteresis.
In particular, the vibrations caused by the road surface will cause your body to jiggle about, and virtually all of the energy used to jiggle you is lost in your body as heat. In extreme cases, the amount of energy lost can be in the hundreds of watts*, and even a strong rider can't maintain his normal speed (think Paris-Roubaix cobbles, or a poor unsurfaced road) (Bicycle Quarterly). A road doesn't need to be all that rough for these vibration losses to be larger than the hysteresis losses - basically any road that has ever had chippings spread on it.

Comfort is a good guide to how much you are losing to vibration.
It's virtually never worth having tyres that are harder than is comfortable, particularly as with quality tyres the reduction in hysteresis losses with increased pressure is small (the losses are low even at low pressure, so there's less to gain compared with heavy, stiff tyres).

[Brucey]

More to it than the folding.
The Pros also have much finer carcass fibres 150tpi v 60 tpi.

if you are happy with a 60tpi vittoria, but you are on a budget and want the lower weight of a folding tyre, consider a Zaffiro Pro.

Cheers

[Bmblbzzz]

More to it than the folding.
The Pros also have much finer carcass fibres 150tpi v 60 tpi.

I have a feeling they might be counting those fibres in a different way for each version. Don't know though. Anyway, it turns out to be far more involved that that; there are Speed, Control and Endurance versions of the Pro, as well as a "tubular" (not sure if it's really a tub but that's what they call it). Along with the standard item.
https://www.vittoria.com/tires/road-tire/

I was thinking of the plain Rubino Pro, but whether the ones I know (a few years old) are the same as the ones they make now, I wouldn't like to say.

[Mattievrs]

Are these the Vittoria Rubino Pro everyone is on about?

http://www.chainreactioncycles.com/vitt ... prod144357

[meic]

Yes but later "improved" ones so more expensive than the ones which I use.