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New tyre time - 25mm-28mm?
That time for new rubber and interested to know what people ride on.
Since starting road cycling over last 5 years ive always used 25mm tyres, my last bike came with 26mm S-works turbo tyres, but thinking of going back to conti gp5000's.
Ive read a lot about 28mm maybe being more comfortable and a wiser choice these days, especially on british roads, but then generally was happy with 25mm when i used them.
In terms of my riding style I dont really race but do the odd sportive, and do like to push myself and break strava segment times etc., so looking for good performance as well. does 28mm suffer performance wise at all?
Also not going to fit until through worst of winter - but looking to buy soon if i can.
Interested to hear opinions! Thanks.
If you're new please join in and if you have questions pop them below and the forum regulars will answer as best we can.
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30 comments
Thanks all for input, all very helpful. My wheels are below:
https://www.specialized.com/gb/en/roval-c-38-disc-wheelset/p/159158?colo...
One thing ive picked up on - Rim width is 26.6mm external and they came with 26mm tyres. Would 25mm maybe be a bit thin for these rims?
I think im edging towards the 28's, there doesnt appear to be much downside and allegedly less resistance?
21mm internal width from that page.
I'm not sure what the current expert opinion is but this esteemed publication has an article on tyre recommendations and they replicate a Schwalbe table that suggests 21mm inner is a bit wide for even 28s. Apparently CTC use a 1.8 multiplier! Note the blurb say these are multi-purpose including gravel and cross, so clearly targeted at larger tyre size capacity.
I know when I bought my Racing 5s 6 or 7 years ago, they'd been updated so 23s were no longer compatible.
As I say, I don't really know what I'm talking about when it comes to the detail but I think you are being encouraged to "Go Large".
That's strange then isn't it that they came with 26mm fitted?
The tyre will stretch across the internal gap so don't get too hung up on external width of the rim in comparison to tyre width.
The 25mm tyre I have on one wheel is nearer to 27mm wide and the 28mm I have on the same model of rim is nearer to 29-30mm.
https://www.vittoria.com/ww/en/stories/tech/etrto-bike-tires
gives a chart for combinations of internal rim width and tyre size.
One figure accurately determined by me: there is less than 5% difference between times over the same 50k course comparing a Merlin titanium 25mm tyres 9 speed Ultegra and a heavy steel Vitus gravel bike 37 mm tyres 9 speed Sora. Of course 5% is a big difference in a race but a small difference for an individual
28 mill allways !
25 mill is not faster ! The comfort gained will improve your riding.
Been on 28 mill for 5 jears now never looked back ..
25mm for the summer (they are faster), 28mm for the wet winter commutes (bit more grip).
I've ridden everything from 23mm to 47mm in recent years and yeah, the wider you go the slower you go/or is harder work to do the same speed...but you do obviously get a bit more comfort.
Regarding potholes/broken road...doesn't make much difference. On a slower bike (fat tyres I mean) you spend longer on the brokjen surface in my experience and so it doesn't seem better than skinner tyres that go faster and spend less time on them. That's my purely personal experience on the crappy long distance london commute I have. If you're not worried about speed so much then 100% go for wider tyres though
Not sure that's right if Conti are to be believed:
https://conti-tyres.co.uk/latest-news/165-wider-tyres-go-faster
this is the conclusion reached by the tyres companies and the pro race teams. But some
ludditespurists are still claiming thinner tyres are faster.But I'm not sure how much faith I put in analysis that uses terms like "generally faster" and "more enjoyable" as its success criteria, their own graph shows a Conti 23 has less rolling resistance than a Schwalbe 23, 25 or even 28,so what is it attempting to prove again?
That said I stick with 30s,though becoming harder to source,and 32s, I just dont claim any great science behind it except they seem to do the job I ask of them which is cope with imperfect roads,trails & farmland tracks covered in mud,gravel & flints
On a perfectly smooth surface like a velodrome, 23s may well be faster, but when dealing with UK roads wider tyres at low pressure will provide a comfort benefit with at least as good performance.
Any differences will be very small. I guess it depends whether you want your ride to be to "more enjoyable". Bear in mind that Continental are naturally wanting to push their product and get people talking about it.
Meanwhile if you want some further online content on this topic then both GCN and bikeradar compared 26mm and 30mm Pirelli P-Zero tyres this year:
https://www.globalcyclingnetwork.com/video/thin-vs-wide-which-tyre-is-ri...
https://www.bikeradar.com/advice/buyers-guides/are-wider-tyres-faster/
In the end the best way is to try them and see for yourself.
Though both GCN & BikeRadars test proved the same thing again, the 26s were faster than the 30/32s,when setup correctly, and it's down to purely subjective feel ultimately which you prefer to use.
As I said I'm happy with my 30/32s, but I dont claim they make me ride any faster.
I ride a high spec Defy for club rides - it's of an age where 28s are the max the frame would take. Previous mild winters I'd rigged up decent mudguards but that limited me to 25s, but it took an expensive hammering a couple of winters ago so decided I wasn't going to do that again. I've been riding 25 tubeless all year. (2 years without a noticeable deflation on Schwalbe on the front and Conti on the rear - I have worn out the rear, hence the mismatch).
Having ridden my old Kinesis T2, the experience was so depressing - mainly being unable to stop the beast with Tiagra levers and long drop brakes - I decided that as I wanted to keep my winter mileage up, I needed another.
I got a Giant Revolt, carbon, so the frame is not far away from my Defy, but it takes big tyres. It has been easy to fit full solid guards with the Gran Fondo 32mm tubeless - 50psi front, 60 rear.
The comfort is unbelievable, and though the wheel/rubber combination is a bit heavier, it's all good as our winter rides are slower anyway. It also feels a lot safer as less inclined to avoid niggly little potholes that is never have risked in my 23mm tubed days, just in case.
In terms of general performance, at 78kg (6' so not a porker) I still have issues drifting off the front on slight downhills - nothing more irritating than having to brake on the front to keep the ride together, so it runs pretty much as well as my Defy.
Given so many roads are double layered - the top repair partially worn off, especially under trees, the comfort is not to be dismissed on a 70+ mile ride.
In terms of handling, 32s plus disc is a joy, and certainly have noticed increased stability on mud and leaves down the grotty country lanes we take to to keep the Nigels happy.
Ride 25's most of the year and find they are nice and fast for me giving me thr grib I need. I do ride 28's on my wet weather/winter bike because I just want some more rubber on the ground to help with greasy roads and also have slightly better protection against potential punctures.
Hard to comment if my 28's are slower or not because the bike I ride them on is Al frame instead of Carbon, so naturally it's a slower bike.
I use 32mm GP5000s and think they are fantastic. If your frame can take them, I don't see any downside.
On a downhill segment that I must have ridden 0+ times, I set a segment PB on my first time with the GP5000s. It's one of those where you pretty much roll down and let gravity take you so I'm convinced it was all the tyres.
I've had one puncture in about 4000km, however, I can caveat that with the fact I've been using the bike less for communing over the last couple of years and may be more selective of when I ride.
Is that because of the lockdown ban on group rides?
Conti GP5000's all year round for me, 25's but if there was room in the frame I would use 28's
I've raced on GP5000 in 28mm width (I'm 70kg before we get on to any kind of rider weight debate
)and it wasn't the tyres holding me back! I'd probably buy either 25 or 28 depending on which were cheapest or available at the time. Or as others have suggested the ones which fit your frame clearances and wheel width. GP5000 are a fantastic tyre, I think they felt noticeably better (faster/easier rolling) than the Hutchinson Fusion and Vittoria Corsa's I had on othe bikes.
I wouldn't go as far as 30mm GP5000 as I know it's a different sort of tyre but the Spec Roubaix tubeless I have in 30/32 is somewhat sluggish and seems to lose the zip of a narrower road tyre.
I mostly ride on rough roads, so I'm on 28s. I'd probably fit 32s if my bike would take them.
The performance difference between 28s and 25s is going to be tiny, so if you're not racing I wouldn't worry about it. Max pressure for my tyres is 115 PSI, so it's not like I can't pump them up as hard as I want to on the rare occasions when I ride on smoother roads.
The roads I ride are so broken and potholed that I am thankful to be on 45mm tyres at about 2.5 - 3 bar. When, occasionally, I am visiting other regions where the roads are better, I just pump the tyres up a bit more. I'm not sure whether there is any penalty for having fatter tyres, but I am sure that I would break something, either the rims or myself, if I was riding on skinny tyres.
Not a direct answer to the question but worth checking out -
https://www.bicyclerollingresistance.com/
Lots of tyre comparisons for rolling resistance and also durability.
I ride 25s at 115psi. Not too worried about comfort.
I think it depends on quite a few factors:
-Current rim widths, external and internal.
-Do you have the clearance to fit a bigger tyre? Remember it's not just about width but height too so check clearances at the seat tube (I fell foul of this when I tried fitting 30mm).
-Also, what weight are you? If you're on the lighter end then I'd stick with 25mm as the lighter weight of the tyres would be more beneficial.
Like that "fatty" (your word) Colbrelli taking Paris-Roubaix on 30mms, or the 15/25 teams in this year's Tour de Flandres who used a minimum 28mm tyre? Your sad obsession with banging on about other people's weight is extremely disturbing and would appear to indicate underlying psychological problems - or maybe you're just plain spiteful and judgmental.
You can't make a simple comment about tyres without airing your obsessive and often offensive views on heavier people (views which in this instance are totally wrong, if 28mm tyres are only for fatter people why are so many pros riding and winning on them?). Keep on doing it and I'll keep calling you on it until you follow your own advice by growing up and stopping calling people with weight problems "fatty".
So 32mm and 37mm are for real PORKERS, are they? FFS.
Just because you use 25mm does not mean wider tyres are only for overweight people. My teenager daughter rides daily on 37mm tyres but weighs about 35kg.
I have 32s - they are great for the potholes and general uneven roads here.
Still on 23mm here.
I've changed from 25 to 28mm. The main difference I've noticed is that it allows me to run lower pressures for increased comfort on rough roads - around 50-55 psi instead of 65 psi. If you can fit them then there's no downside.
Some RR info here:
https://www.aero-coach.co.uk/time-trial-rolling-resistance-data
and
https://www.bicyclerollingresistance.com/specials/grand-prix-5000-compar...