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Laddie-147.
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July 22, 2013 at 6:53 am #19420
MattFr
I know I’m going to get all sort of responses, but I’m currently thinking of going to 25mm tyres after a number of people have told me the advantages of the lower rolling resistance. What I’m wondering is would you use them for both racing and training? And I guess does rider weight (64kg) make a difference to tyre choice?
Also what would be the clincher of choice? In an ideal world I’d opt for an open tubular type for best, and a cheaper training tyre, but I’m not sure this is an option at the moment. -
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Miles253
I’m thinking of doing
I’m thinking of doing similar, what pressures did you run the 23’s at when compared with the 25’s?
stealth
25’s will fit in my Planet X
25’s will fit in my Planet X ProCarbon, but you have to inflate them once they are in the frame & you can’t fit guards then (not even CrudRacers), so I’m limited to 23’s for the winter. But as I don’t have wide rims, that isn’t bothering me too much.
53x11
It’s an old topic, but too
It’s an old topic, but too fun to not comment, and someone else did post today…Yes, a one-wheel solution is inherently a compromise, but in the less elite race categories, the gap between riders will be more significant than differences in their equipment. You can worry about equipment way too much. I hope that the original poster got his 25s.
When you do get a set of race wheels, you can stop worrying about making your training wheels “fast.” Horses for courses. Wheels that don’t get raced can be heavier, more durable, and more comfortable.
There is a category of rider who wants fast training wheels to “win” training rides or century rides. Apart from triathletes, they must be the people buying carbon clinchers. A coach and a power meter might make them faster, but who am I to say that their form of recreation isn’t valid?
dave atkinson
get some 30s. Challenge are
get some 30s. Challenge are making some nice ones 😉Kadenz
There was a very interesting
There was a very interesting article by Richard Hallett on this very subject. I think it was in last week’s Cycling Weekly, but it might have been the week before.As I recall it, he comes down in favour of 25s on the grounds of lower rolling resistance and greater comfort than 23s.
movingtarget
ilovemytinbred wrote:for
Yup. There's an informative discussion by the lead engineer at Zipp on how going from 23 to 25 will marginally decrease your rolling resistance and save you ~0.3 watt but the increased air resistance 0-6 watts can penalize you. They're still in the 23 camp, esp since the tire rims have to be bigger for the wider tires further increasing your drag. http://velonews.competitor.com/2012/03/bikes-and-tech/technical-faq/tech-faq-again-bigger-tires-roll-faster_209888ilovemytinbred wrote:for racing a narrower tyre is likely to be better than a 25. It depends on the wheel, but at racing speeds you will lose more speed through drag (maybe 5 watts) then you will save through lower rolling resistence (< 1 watt) These are small differences, that you would never notice in training where comfort is more important, but there is no way in hell I would use a 25 for a TT.For winter tires I've switched to 25 Continental GP 4-season (great traction and puncture resistance, Portland roads are wet, filled with debris with some brick paving thrown in for fun) and run 23 Vittoria Rubino Pro III in the summer although just bought some Veloflex Corsa's to try cuz I've heard such great things about them. Vittoria & Veloflex used to be the same people but Vittoria split off and sent their production to Thailand and Veloflex is still handmade in Italy and cheaper. Used to ride Vittoria Evo Corsa 23s which are very fast and corner well but punctured like crazy and didn't wear well, just 500-700 miles which is too expensive (for me) to be replacing them that often.
VeloPeo
levermonkey wrote:Moved from
levermonkey wrote:Moved from Continental GP4000 23c to Continental GP4000 25c last year.The only difference I’ve noticed is the increased comfort.
Exactly the same here
Anonymous
Moved from Continental GP4000
Moved from Continental GP4000 23c to Continental GP4000 25c last year.The only difference I’ve noticed is the increased comfort.
joemmo
chrismday wrote:KiwiMike
chrismday wrote:KiwiMike wrote:I swapped from 23 to 28 (Gatorskins) 6 months ago. Apart from only having had one flat in over 3,000km, I’m faster and have no more wrist/bum pain from vibration on poorly-surfaced roads. I follow the 15% drop rule – http://goo.gl/fkCwA – so for a 70kg rider + 10kg bike, I run 80psi rear / 50psi front.This might be heresy to those who ‘know’ different, but the science says 15% drop and a larger tyre means same or lower rolling resistance, less fatigue, and fewer punctures.
That’s very interesting; so you’ve not had any issues with pinch flats or damaged rims hitting the edges of holes with such low pressures?That is interesting, I run 28s on my commuter bike and have found 80psi on the rear about right for the rear just by trial, error and feel – which more or less tallies with the chart. I tend to run the front higher than the 60 recommended there though, too many deep, sharp edged potholes to risk lower.
BBB
In terms of volume 25mm tyres
In terms of volume 25mm tyres are around 18% larger and therefore can be run at around 20PSI less. The difference is certainly NOT marginal.Gains on rolling resistance with 25mm tyres are certainly greater than 1W when tested on real roads, not steel drums. The worse the road surface, the more significant gains (largely thanks to lower pressure not width per se).
KiwiMike
chrismday wrote:
That’s verychrismday wrote:
That’s very interesting; so you’ve not had any issues with pinch flats or damaged rims hitting the edges of holes with such low pressures?Sorry, just saw this 😉
No pinch flats here, or on any of the club bikes running 28’s at similar pressures.
ilovemytinbred
for racing a narrower tyre is
for racing a narrower tyre is likely to be better than a 25. It depends on the wheel, but at racing speeds you will lose more speed through drag (maybe 5 watts) then you will save through lower rolling resistence (< 1 watt) These are small differences, that you would never notice in training where comfort is more important, but there is no way in hell I would use a 25 for a TT.
Simon E
700c wrote:I must be a bit
700c wrote:I must be a bit mad running my tubs at 140psi! Higher for TTs, but it works for me..I have read that tubs roll well with higher pressures but I’d not want to race on Shropshire roads at that. A friend of mine is a bit lighter than me. She uses Conti tubs on her Navigators and doesn’t normally go over 100 psi.
700c
Simon E wrote:700c
Simon E wrote:[quote=700c]Conventional wisdom is 23 for racing,.I understand. (I don’t race), but comfort is not as much of a factor, they are a little lighter, plus unless you don’t get the more aero limitations on conventional width rims (bulge of tire over and above brake track width)Marginal gains and all that…
But this is just theory, and if you prefer to be comfortable you might find wider is more beneficial than narrow tires
No-one wins or loses because of 2mm of tyre width or 20 grammes difference in weight. Those gains are at the thinnest end of marginal. But a 25mm tyre does give you a greater volume of air so a little more comfort, though IME it’s not ‘night and day’.
Pressure can make quite a difference, mainly because too hard a tyre will be bouncing you and your bike around instead of deforming and absorbing surface irregularities. I’m 62 kg and for racing I put 100 psi in my Ultremos for smooth courses, 90 psi on the rougher ones. Was happy with ~80 psi in the 25mm Vittoria Rubino Pro 2s I had. I began racing club TTs on 28mm Bontrager Hardcase tyres (talk about making it harder!) and one night I forgot to check the rear – it was just 40 psi yet it didn’t seem to make much difference!
If you were another 10 kg heavier I’d add 5 psi to those numbers but every rider should establish their preferred pressures.
More tyre suggestions – http://road.cc/content/forum/88042-help-tyre-choice%5B/quote%5D
Well yes, hence the term marginal! The OP wanted to know the difference between 23 and 25 mm tires. That’s a question about marginal issues!
On another note, I must be a bit mad running my tubs at 140psi! Higher for TTs, but it works for me..
Simon E
700c wrote:Conventional
700c wrote:Conventional wisdom is 23 for racing,.I understand. (I don’t race), but comfort is not as much of a factor, they are a little lighter, plus unless you don’t get the more aero limitations on conventional width rims (bulge of tire over and above brake track width)Marginal gains and all that…
But this is just theory, and if you prefer to be comfortable you might find wider is more beneficial than narrow tires
No-one wins or loses because of 2mm of tyre width or 20 grammes difference in weight. Those gains are at the thinnest end of marginal. But a 25mm tyre does give you a greater volume of air so a little more comfort, though IME it’s not ‘night and day’.
Pressure can make quite a difference, mainly because too hard a tyre will be bouncing you and your bike around instead of deforming and absorbing surface irregularities. I’m 62 kg and for racing I put 100 psi in my Ultremos for smooth courses, 90 psi on the rougher ones. Was happy with ~80 psi in the 25mm Vittoria Rubino Pro 2s I had. I began racing club TTs on 28mm Bontrager Hardcase tyres (talk about making it harder!) and one night I forgot to check the rear – it was just 40 psi yet it didn’t seem to make much difference!
If you were another 10 kg heavier I’d add 5 psi to those numbers but every rider should establish their preferred pressures.
More tyre suggestions – http://road.cc/content/forum/88042-help-tyre-choice
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