25 or 28 tyres?

apreading

Have ridden the last 4000 miles on the Vittoria Zaffiro 700x28 tyres that came on my Boardman. Totally happy with them, but wondering if there is something better out there when it comes time to replace...

Found the switch from MTB to road harsh enough in terms of ride quality already, so didnt want really skinny high presure tyres. I like with the 28s that I can have a little lower pressure for comfort.

To that end, I bought a pair of Conti GP4 Seasons a couple of months ago. Havent got around to fitting them yet but having done a few sportives and audax recently, most others are on 23s or 25s. I am now wondering whether a switch to 25s would make much difference to effort/speed over longer distance rides? Considering the GP4000S 700x25.

So, given that I am ruling out 23s, would I notice a significant difference between 25s versus 28s? Should I get some 25s for summer and keep the 4 seasons for next winter?

Or should I just stick with the 28s?

goonz

23's!!!!!!!!

I made the switch right from mtb to 23mm, it was a bit daunting at first but now I love it. I'd hazard a guess on 23 you are less likely to puncture too.

apreading

I seem to have repeatedly read about wider tyres actually rolling better too - so what is the advantage of having skinnier ones? Or is that a myth...?

Dont use the P word(!) - if that were a consideration, I would stick with the Zaffiros (1 'P' from a thorn on my driveway after a tree pruning, in 18 months and 4000 miles). There - I have tempted fate now... That one occasion was within a week of my last telling of how good my record was!

cookeeemonster

I went from 23's to 25's and found them noticeably more comfortable, with no loss of speed.

Went from 32's to 28's on my hybrid and found the 28's to be noticably faster (on my long commute) but with not much difference in comfort...

...so your 28's should be fine, but next time you come to buy a set of tyres you might wanna try 25's just to double check?

understand though that different makes and types of tyre will also affect everything!! (so to compare properly you need to use the same 25 tyre as the 28 it's replacing)

Frank pole

25 defo more comfy than 23 and just as fast( for me anyways ) - if you have a pair put them on and see!

displacedaussie

I race (and train) on the 25mm GP4000S. I'd never go back to 23m ones.

goonz

Hmmm interesting I may try 25's...do they fit the same rims no problems?

apreading

Should be OK on your Scott Speedster according to the interweb: http://forums.roadbikereview.com/scott/ ... 01194.html

More important than the rims is probably the clearance round the frame - you might not be able to do a 28 but I reckon a 25 will be OK.

Interesting review here: http://www.roadiemanila.com/2013/03/rev ... s-23c.html

I blame wiggle for all this as I am hovering over the 'buy' button on the 4000s tyres in 25c...

maddog 2

25 on the fast bike

28 on the commuter

23s on nothing

animal72

maddog 2 wrote:

25 on the fast bike

28 on the commuter

23s on nothing

+1

apreading

What if my fast bike is also my commuter?

Would it be worth considering a 25 up front with 28 rear where most of the weight is?

rjkflyer

apreading wrote:

What if my fast bike is also my commuter?

Would it be worth considering a 25 up front with 28 rear where most of the weight is?

I would consider what tyre pressure you should be running before considering changing tyres.

Most people run too hard - wastes energy and is uncomfortable. The correct pressure is entirely linked to weight (you plus bike) and you would be surprised what is actually correct.

I have 25s, weigh 63 kg, have a 7kg bike and so run 60/80psi. Maybe +5 on that occasionally. And GP4 Seasons.

Take a look here: www.bikequarterly.com/images/TireDrop.pdf

If you are a really heavy guy, then yes, considering 28s may give you what you feel best with, but 25 is really the 'sweet spot' if you can run them without excessive pressure.