How much difference does tyre width make.

[Mick F]

I remain to be convinced.

My Mercian won't take anything wider than 25mm so I can't do a comparative test with a variety of widths.
Having ridden with loads of different people over the years doing End2End and passing through, there's a wide variety of bikes people use. Without fail, my Mercian freewheels faster than anyone else except one. Sorry, can't remember who it was and on what bike, but we freewheeled neck and neck. One, I remember, he had to pedal to keep up with me.

Riding with someone two abreast (chatting) down a long gentle hill ........ heading west on the Old A30 for instance ........... I have to keep dabbing my brakes to stay alongside.

I'd challenge anyone to a freewheeling competition - no aero tucks allowed - just sitting on the tops and chatting.
You pick the road.

[reohn2]

Mick
Roll down tests mean nothing in the overall scheme of things.
What does matter is energy expended in real world riding,uphill and down dale over long rides,and even then different people may find a fatter tyre faster,ie; if you are comfortable more of your energy goes into turning the pedals,road buzz or high frequency vibration can be tiring on a long ride whereas a smoother ride won't be,so energy output is better and more consistent because of the comfort.
You may say my bike is very comfy on 25mm tyres because it has a nice springy frame and fork,but what if it's even more comfy on say a 32mm tyre of the same make?
The effects of comfort of the rider can't be stressed too much,not everyone is the same whether that be due age or health,etc ie;I suffer from Osteoarthtitis quite a lot in most of my joints and would find your bike uncomfortable which would not only limit my ride time but because of the discomfort limit my speed,especially on UK crapmac and chip n seal.
Comparing wide tyres with narrow isn't a simple equation,there are a lot of other factors to consider,some unseen unless direct comparisons are experiemented with by the individual.

[Audax67]

I ran my old Ti Warhorse on 23s for 15 years, but I put 25s on the other day, and the change in comfort is remarkable. The effect on speed I couldn't say, because there was a powerful wind blowing. I had the impression that there wasn't much difference.

[Jamesh]

Also remember that some tyres come up smaller than others. Michelin pro4 balloon up to 25mm whilst wiggle life lines are 23mm both are nominally 25mm tyres.
Also some tyres are really quite heavy spez armourdilios I found to be really heavy and slow in 28mm form.

Cheers James

[Mick F]

R2.
Not talking of roll-down tests.
Not talking of energy expended uphill or downdale.

I'm saying that I remain to be convinced due to my experiences with others freewheeling down long gentle hills.
Maybe 15-20mph on the tops relaxed and chatting side by side freewheeling.

You pick the hill. Not steep, just gentle and long and quiet where we could freewheel side by side and chat.
Any road you could mention.

I remain to be convinced.
Experience is everything and your experience could well be different to mine.

[reohn2]

Mick
Freewheeling down hill is a roll down test is it not?
Plus there are far too many variables in such a test to prove anything,weight of rider and bike for one.
So it proves nowt.

FWIW Mike Burrows did some roll down tyre tests,M+ tyres came out fastest,but good luck with riding them up hill and down dale

PS,one of us is missing the point of the thread.

[thelawnet]

R2.
Not talking of roll-down tests.
Not talking of energy expended uphill or downdale.

I'm saying that I remain to be convinced due to my experiences with others freewheeling down long gentle hills.
Maybe 15-20mph on the tops relaxed and chatting side by side freewheeling.

.

It depends on the gradient.

1% is worth about 75W. At 20mph in any model rolling resistance is of quite little relevance next to air resistance.

If you were freewheeling at 10mph that would be quite another matter as rolling resistance would be the dominant force

[belgiangoth]

There are many confounding variables:
Different types of tyres in different widths will be very different
Even the same make of tyre will be different in different widths
The frame you ride on may be so stiff that the change to narrow tyres is significant or you might ride a frame which cushions some of the buzz, meaning that a move to narrower tyres is less noticeable
Ditto the way you set up your bike (drop to handlebars)
Some people are more susceptible to the discomfort from road buzz and/or potholes
Some people have worse local roads
Which is faster will depend on other things such as aero position on the bike or quality of hubs for freewheeling

All this adds up to conflicting correct information and highly conflicting views.

My experience a couple years back moving from 32s (kojaks) to 23s (ultremos) was that the acceleration difference was marked , climbing was no different and comfort was not noticeably different. Then I punctured like crazy on the thinner tyres and now I am on 38s (overrides).

[mattsccm]

Not sure that I can be buttocked to sort it out but here we have both the subjective and the objective mixed up which surely isn't ideal. To decide what piece of equipment is most effective we have to first decide using all the factual issues. Can't argue with them. Then we chuck in the real world issues that pop up when the human element is thrown in. This includes ( to list a few )different frames, bodies, brains and uses. Those make most comparisons largely irrelevant.

[Mick F]

Yep.
You summed up very well.

It's just from my experience with loads of riders all shapes and sizes and on different bike riding side by side together, and my bike more often than not rolls faster.

Why?
My guess is better tyres, but it's only a guess based on what I see.

[pwa]

I freewheel downhill faster than other members of my family when we cycle together but I've always thought that was mostly due to me being heavier

[Cugel]

R2.
Not talking of roll-down tests.
Not talking of energy expended uphill or downdale.

I'm saying that I remain to be convinced due to my experiences with others freewheeling down long gentle hills.
Maybe 15-20mph on the tops relaxed and chatting side by side freewheeling.

You pick the hill. Not steep, just gentle and long and quiet where we could freewheel side by side and chat.
Any road you could mention.

I remain to be convinced.
Experience is everything and your experience could well be different to mine.

Going down hill efficiently is something of a craft. There are many aspects to going down hill efficiently, especially when doing so without pedaling. It's actually quite difficult to describe all thes downhilling aspects in words. It involves the feeling of, and adaptation to, many factors.

When I go out with others, whether novice or decade-long club members, I often go down faster than they do. On significantly long slopes I can be a hundred yards or more in front from freewheeling down only, no pedalling.

Is this years of practice? (I always liked to go as fast as possible downhill and also to save energy for not the next uphill by not pedalling down). Do I have a particulalrly sleek frontal area? Does it involve my softish 30mm tyres (Schwalbe G1-speed) vs their typically rock 'ard 23 or 25mm? Is it better cornering lines? Can I lean over safely farther than others? It's hard so say as there are so many factors.

But I can certainly say that those 30mm types at about 55-65psi under my 13st 0llbs don't make me slower. They seem to go very well on the flat too. They don't bounce my 13st 0llbs up and down on the scab-roads like those narrow things I once used did.

Cugel

[David9694]

https://www.bicyclerollingresistance.co ... ke-reviews

Interesting site here.

[RickH]

I freewheel downhill faster than other members of my family when we cycle together but I've always thought that was mostly due to me being heavier

Probably at least partly true, combined with the natural aerodynamics of your usual riding position &, possibly more important*, clothing.

(*Hence all the efforts in the pro peloton to use different fabric textures in different places on the kit to control airflow over the rider's body to improve performance.)

[NEvans]

My general thought would be to go for the 28c for some comfort and durability, but is there much difference between them?

Hope you don't mind me asking but what is the road quality like where you live? How fast and far do you normally cycle? How fast and far would you like to cycle? And how do you use your bike?

I live in Woking, Surrey where I can only class the average road quality as sh1t. Council have this thing about coming round and sticking in a bucket of tar. Couple of cold and hot snaps and there's holes everywhere.

How Far; Sunday morning club runs are at an easy pace to the coffee shop around trip of about 25m, time and decent weather generally push this to around 40-50m. Famous last words but I should have more time on my hands this summer, so hopefully longer runs of 80-100. Not fast, mid 50s 18st, I just enjoy being out on my bike rather than racing everyone else I see out on the road. So comfort over speed.

Earlier this year broke my Orbit Harrier (road went right, I went straight on), which has always had continental 24s and more recently 28 Four Seasons. Just brought a Pinnicle R1 which says happy to have upto 45 on, and still fit mudguards.