I bought a new 25mm Michelin pro3 tyre off eBay a bit back. I thought I'd bought a 23, but that's my fault for not noticing!
Honestly how much of a difference is 2mm gonna make? I have mounted it on the back and at 120psi it feels fine! Sure it'll be marginally heavier, but if I put the same on the front is it likely to have a huge effect?
Cheers
Word on the street is that 25mm tyres are faster than 23mm tyres..
Wouldn't run em at 120 psi though, as I don't want me teeth to rattle out of my skull 🙂
[url] http://inrng.com/2013/04/reinventing-the-wheel-25mm/ [/url]
what ian says.
you will not notice a difference except when cornering when you should (theoretically) have more grip so higher speeds.
As Ian says. An article in the latest rouleur suggests that pretty much all race teams are moving to 25mm tyres now as they've been identified as faster.
Funny, this morning, I've been taking a closer look at 28mm like the Hutchinson secteur. Doubt they''re faster but they will be more comfortable. Over a long enough distance, that will be faster.
Part psychological, though... Roadie mate of mine has just gone back to skinnier tyres, he's not sure if they're faster or slower, he just prefers the riding-on-an-iron-bar feeling of tiny tyres at silly pressures- it feels fast, and it feels like he reckons road bikes should feel. I can't abide it personally, but that's because I'm a terrible roadie.
It's like my rigid mountain bike. Feels incredibly fast. No doubt it would be faster with bouncy forks, but then it would feel soft and weak rather than brutal.
Less pressure and a wider tyre especially with a wider rim means more comfort, less rolling resistance and more grip.
People still overinflate their tyres as they think it means they go faster. It doesn't.
They are the same people who think a road bike tyre needs siping (tread pattern) for it to grip in the wet.
28mm tubeless here, I find them much more comfortable and faster over my local pot hole riddled roads, not sure if I would see any speed advantage on a smother road, but certainly faster in general for me.
I raced at the Tour Series Crits and Prem calendars, We use 25mm Tubs and tyres pretty much all round now in our team. Personally at 85kg I run 80-100 psi dependent on conditions, never any more than that though as it's slower.
28mm Conti 4 Season on CX rims here.
Run at 95psi. Kept up okay with roadie mates on 23s and my arse thanked me for it.
schwalbe have a brilliant, detailed technical document on their website.
ime 25mm at same pressure as 23mm has less rolling resistance on perfectly smooth road. reduce pressure to get same RR as 23mm tyre on smooth stuff = far better rolling and comfort on actual roads. this is based on otherwise identical vittoria rubino pro3s. I now run a 26" commuter with a 1.3" slick up front and 1.5" rubino slick rear and can't believe the speed benefits on rougher roads.
Womp, what tyre is that with?
hutchinson secteur on farsport rims
As Ian says. An article in the latest rouleur suggests that pretty much all race teams are moving to 25mm tyres now as they've been identified as faster.
hmm, Article i saw written by Vittoria was saying only 40% of their riders were on 25mm at the Giro....
v12jat - Member
...Honestly how much of a difference is 2mm gonna make? I have mounted it on the back and at 120psi it feels fine!
try it at 90psi... (unless you're a massive great biffer)
Sure it'll be marginally heavier,
about 20grams - woo.
but if I put the same on the front is it likely to have a huge effect?
you might lose fewer fillings?
Cheers
no problem.
Womp, those are the tyres I'm looking for. Where did you get them and what do you reckon to them?
They seem great, comfort and puncture protection was my key critera, iv only done around 600 miles on them with no issues, I ride pretty hard though rough roads and take in a few off road sections on route. Strava confirms they are as fast as my GP4000 on normal roads and faster on rough stuff (this may be due to me pushing harder as I'm not concerned about flats the same)
http://www.worldclasscycles.com/hutchinson_sector_tubeless.htm
Conti reckon 25 has less roll resistance. All teams running conti in the tour will be on 25 so the rep told us
Cheers Womp. Didn't realise you were across the pond. I can't find any of them on this little island so far.
[i]hmm, Article i saw written by Vittoria was saying only 40% of their riders were on 25mm at the Giro.... [/i]
Fair point, just re-read the vittoria article in Rouleur and it says 'many teams'.
I'm not across the pond, just ordered them from over there because as you say they are not available in the UK yet
Fair point, just re-read the vittoria article in Rouleur and it says 'many teams'.
not to argue, but i also wonder what Vittoria mean by on 25mm as well, If you think about the pave classics there is a tendancy to upsize tyres, I can't remember every stage but would riders change tyre depending on the days stage? Ignoring the team sky and having crap tyres for some of the wet stages thing.
Awesome, got a matching front ordered now! Will run a bit lower pressure too.... As I'm not a great biffer!
This:
28mm Conti 4 Season on CX rims here.Run at 95psi. Kept up okay with roadie mates on 23s and my arse thanked me for it.
I keep referring to:
[url= http://m.bikeradar.com/gear/article/bicycle-tires-puncturing-the-myths-29245/ ]Rolling resistance test[/url]
Looks convincing.
It's on a link in the article in a previous post above, I've had it saved for a while now.
Serendipity!
MrSmith - MemberLess pressure and a wider tyre especially with a wider rim means more comfort, less rolling resistance and more grip.
People still overinflate their tyres as they think it means they go faster. It doesn't.
They are the same people who think a road bike tyre needs siping (tread pattern) for it to grip in the wet.
I'd have agreed with you, but the science doesn't apparently!
http://m.bikeradar.com/gear/article/bicycle-tires-puncturing-the-myths-29245/
Tread pattern matters, even on the road: The importance of tread pattern is no surprise to the off-road world but common wisdom says it's a non-factor on the road, where slick treads are assumed to deliver the greatest surface contact with the ground and thus, the best grip. However, asphalt is far from a perfect – or even consistent – material. Certain tread designs can provide a measureable mechanical adhesion to the ground.
My shiny new 700x25 GP4000Ss went on the bike today, not had a chance to test yet but can't wait for the mesmerisingly high speeds I'll be certain to achieve!
I'm not going to take what wheel energy say as gospel. They say 23’s are more aero but its not as clear cut as that ask zipp. With wider rims and the different profile they give a tyre plus the tyre/rim acting as a whole aero shape mean a 25 could possibly be more aero and have less rolling resistance.
They mention tread on tyres but give no data. Sheldon was right, you need to do insane speeds to get a tyre to aquaplane. They are right about asphalt though, its not smooth and carcass deformation over those micro bumps is very important.
They are the same people who think a road bike tyre needs siping (tread pattern) for it to grip in the wet.
I'm one of them. How much of it is just in my head I don't know, but the only road race I've won this year was in the pouring rain.
Have you also noticed that some of the tubular versions of popular tyres have file treads?
I should say I go for file not siped (if that's even a word)
Edit; I train on 25c Vittorias, and race on 23c Vittorias, though my race rims are the newer wider ones which seem to make the 23c's appear to be 25c's
A good pliable carcass and rubber compound matter but if you head says no you will never trust a tyre. 😕
I am running 23 on the front and 25 on the back.
Seems to work fine.
The main reason is I needed a new tyre at the back as the front one was not worn & I felt as a 100kg rider it might offer protection against flats.
So far I have not died!
I've been running 23's at 120psi as the bike came with them and I thought rock solid was faster....might have to experiment. What sort of psi should I be running then? Very rare for me to be on perfectly smooth Tarmac.
depends on bike+rider weight and front:rear weight bias. usually better with front tyre lower by 5-15 psi (not v specific, I know). I found 10kg bike with 70kg rider and 5(or so)kg of luggage, 110-115psi rear, 100-105psi front (lower in the wet or if I wanted 'pampering')
there are various calculators online which will give you a ballpark figure.
such bs it's scarry..
I'm 90kg and run 100 front and rear (+/1 5psi depending on when I last blew them up), any more is pointless unless you're significantly heavier and if you're lighter then go with a bit less for slightly added comfort.
I use 25's over 23's apart from on the winter bike at the rear where I can't fit a 25 under the mudguard.
Tread is another oft-debated one, I think most people agree siping for wet weather performance is pointless as aqua-planing is a non-issue. File treads though I can possibly increasing traction as they squirm under load when cornering - I've not seen it tested and presumably the effect is lost pretty quickly when they start to wear. Personally I always use slicks
Lifted from Ted King's Strava when he was asked if the majority of the pro-peloton was riding 25mm
nope. I don't think so. 23 is the standard