Anyone still using 23 C tyres?

[figbat]

My road bike came with 23c - I have replaced them with 25c but that’s as big as it’ll take. In fact even with 25c tyres it’s a squeeze to get the rear wheel on as the tyre fouls the seat tube when at the very front of the QR dropout.

Luckily it makes no difference on the turbo!

 

[FishFright]

Nope. Grip doesn't work like that. F=MuN where F is the available friction, Mu is the coefficient of friction and N is the downforce. Note that area does not feagture. This is THE most misunderstood fact of traction.

That's why racijng cars et al still run on very narrow tyres .....

Grip is not the same as the coeffincent of friction , it's way more complicated and includes stiction and momentary chemical bonds amongst a soup of other variables.

 

[Yellow Saddle]

That's why racijng cars et al still run on very narrow tyres .....

Grip is not the same as the coeffincent of friction , it's way more complicated and includes stiction and momentary chemical bonds amongst a soup of other variables.

By definition friction is not the same as the coefficient of friction. The latter is a dimensionless number and the former is expressed in Newton. Stiction is another name for static friction which is just one of the two types of friction.

Throwing jargon into a salad and dressing it up as complicated won't cut it.

I'll say it again. The friction available from a 23mm tyre is exactly the same as that from a 40mm tyre or any other dimension you'd like to come up with.

 

[Pat "5mph"]

Mod Note:
We are getting a wee bit OT with the friction argument, please stay on topic.
Cheers!

 

[Bristolian]

Can only go up to 25mm on Allez (2008 or 2009), and that's ever so close to rubbing the seat tube. No chance of a mudguard in there!

Have got a more comfortable 32mm on the gravel bike, and still have room for full mudguards.

Mine was manufactured in September 2010 and you're right - no room to get a mudguard between the fork crown and tyre at the front but I can just get my slightly modified SKS Raceblade Pro between the seat stays and rear tyre at the back but no chance of getting it between the seat tube and rear tyre.

One of the reasons I'm looking at a gravel bike is to get wider, more comfortable tyres

 

[Yellow Saddle]

Mod Note:
We are getting a wee bit OT with the friction argument, please stay on topic.
Cheers!

Pat, some people think the meaning of life can be found in carburettors, but they're wrong. It is all about friction.
Seriously, I think friction is a relevant element of this debate, since someone upstream said wider tyres are less slippery etc.

 

[andrew_s]

I ditched 23C for 25C about a decade back.

I ditched them in 1995 after pre-PBP test runs/qualifiers. I was after comfort, but came to the view that they were just as fast provided you got a decent model.
I was on 28, as the biggest that would go under dual pivot brakes with mudguards, until I got a disc brake bike, and immediately changed to 35.

 

[lazybloke]

Mine was manufactured in September 2010 and you're right - no room to get a mudguard between the fork crown and tyre at the front but I can just get my slightly modified SKS Raceblade Pro between the seat stays and rear tyre at the back but no chance of getting it between the seat tube and rear tyre.

One of the reasons I'm looking at a gravel bike is to get wider, more comfortable tyres

Yep, I supplemented my Allez with a Croix de Fer. The geometry is much more comfortable, and the mudguards and wider tyres are good, but the bike is noticeably heavier and significantly slower.
So when feeling sporty it's the Allez. Otherwise it's the CdF.
But the Allez kills me on long distances, so I reckon there's another bike out there for me. Was tempted by a carbon Synapse 700 recently...

 

[Jenkins]

It's not just the tyre size that makes a difference, so does the construction. I've just gone back from 25mm to 23mm on one bike and it's made a whole lot of difference to the ride comfort.

I've been running my PlanetX Pro Carbon on 25.5mm Jack Brown Race tyres which were made for Rivendell by Panaracer and sold through PlanetX for a while and are as below (not my pic)

They should have been good with a folding bead and light weight, but were possibly the worst tyres I've used - harsh ride and just didn't seem to provide any cushioning effect against the local crap roads. Don't know if it was caused by a very stiff and short sidewall - couldn't even do a quick thumb test to check the pressure as there was no give - or a harder rubber on the tread.
I swapped them out for a pair of dirt cheap (£7 each when I purchased them a couple of years ago) 23mm Vittoria Zaffiros this morning and went for a quick test ride - what a revelation. No road buzz, smoothed everything out nicely and I found myself going for a longer ride to try out known crap roads to confirm the better ride.
I suspect that a softer and deeper rubber compound on the tread combined with a taller and more compliant sidewall construction has helped with the improved comfort despite the narrower width and 10psi higher pressure.