Tyre width on a road bike

[oomilegs]

First of all as I'm new to the forum; Hi Everyone.

The roads around where I live are being resurfaced with large grey granite chippings and are not the nicest surface to ride on.
The "buzz" through the frame is quite unpleasant and it's quite a relief to turn off onto an older smoother worn surface, but now
even they are having the dips & pot holes filled in preparation for the tar and chips treatment.
I have a Cannondale Synapse, aluminium frame with carbon forks, thats shod with 700x25 slicks and I wondered if anyone has
experience of fitting wider slicks, 28's or perhaps even 30's ?
My other bike is a hybrid (Cannondale Quick 4) and has slick 30's, and after the Synapse it's a joy to ride on the rough.
I'm thinking 30mm would be too much on a road bike, but would I notice much difference between the 25's that I have now, and 28's ?

Thanks in anticipation,
Paul G

[pwa]

You can put on whatever will pass safely through your forks / frame without a risk of jamming with small stones/ twigs. What wheels / rims do you have? Rims have tyre width limits.

Also, maybe your 25mm tyres can be run at a slightly lower pressure. They don't usually benefit from being pumped up to the max. I can ride those at about 90psi rear and a bit less at the front and I'm not light.

[Spinners]

I quite like this trend towards wider tyres and note that Kona have at least two 'road' bikes (with rim brakes) with 30mm tyres (the Tonk and Esatto - both overpriced IMO but I like them).

I've acquired a 2015 Giant Rapid hybrid frame (with rim brakes) and I'm building it up with drop bars and STI's and hoping to use 30mm tyres on that.

[mattsccm]

For a couple of years I ran Challenge Strada Bianca's in 30mm before swapping to Schwalbe S oOne tubeless, also in 30mm. To start with I swapped back to 25's in the summer but gradually swapped less and now the 30's stay all year. Might stick the Stradas back on soon as they are still fresh.
My roughstuff bike runs 42mm Contis. Way to heavy and solid for pleasant road use though.

[BrownBear]

It's quite funny how the CTC used to be a lone voice saying 28mm plus guards was a necessity for a UK bike, outside of competition. I recall the youth at the LBS sneering at my request to size up. Recently it's become 'fashionable'; apparently, it's been "discovered" they roll better on real roads, which won't come as a great shock to many.....

I have 28mm GP4000II on a 'wide' rim, which measures 30mm, and at around 75/80psi that gives a much-improved ride over chip seal. Personally, I don't think I'd go wider than that for my long distance steed, though my urban bike is a different matter.

[bobc]

My bike of the last 6 years was on 28mm tyres, which are about as big as will go through long drop dual pivot rim brakes. The bike I use now has hub brakes (drum and disc) so I went for as big tyres as I could get through the frame, 35mm.
It is SO nice to ride - rolls great & I no longer even notice road imperfections that would have me swerving previously (so it's more relaxing to ride). Plus there's a big reservoir of air in there, the tyres seem to stay pumped up for months. Others have noted wider tyres' remarkable puncture resistance elsewhere on other threads. I expect they'll last more miles too
OP - put max pressure in your 30mm tyres & enjoy the ride!!!

[oomilegs]

The 25's are Schwalbe Lugano and the wheels are Maddux R 3.0
Measuring the outside width at the rims the wheels are 19.5 mm
I bought this bike second hand, it having done a mere 200 miles so I suspect these are O/E.

The narrowest part of the frame is between the chain stays where it looks like clearance would be marginal for 25's.
A pity, as I have a pair of new Continental Sport Contact.
Maybe 28's would be a happy medium.

Thanks for the help so far,
Paul G


Edit to add:-

I have ordered a pair of 700 x 28c Conti Ultrasport II (wired)
£26.50 didn't seem too much to risk.

Cheers

[oomilegs]

The Conti 28's arrived today and I fitted them in my lunch break.
There was 3mm between the tyre and the chainstay each side and I watched as the drizzle gradually cleared. By 4pm the road was showing a dry line so on with the gear and out for a test run. I know the road to my sons house down to the last second so off I went, pushing a bit as I didn't want to put in a slow time. Only a PB.

I was running 90 psi f & r and the ride was great. No more dodging man hole covers; straight over regardless, and so kind on the bum and the hands.

Soooooooooo pleased.

Cheers everyone
Paul G

[McStumpy]

I have a Focus Cayo with 25mm Michelin Pro4s and a flat bar Triban 540 with Spesh roubaix 32mm. Both feel fast, and the latter is a joy on the rough roads and tracks.

[reohn2]

When I went from 28s to 35s and ended up selling two bikes that wouldn't take the larger tyre size.
I've never looked back,average speed loss is minimal at 0.5 & 1mph over a tested 70mile distance,descending is far and away more surefooted on UK roads(which are truly awful)especially on twisty descents,sometimes as much 10mph faster.
But the biggest plus has been comfort,there is simply no comparison.
There is a catch,you need a good high TPI supple slick to take full advantage of the change in tyre width,if you're going to stick any wide slick tyre on the bike won't work.I recommend Vittoria Voyager Hyper which I use, or similarly Schwalbe Supremes get good reports.
Similarly so tyre pressures need to be correct for load,it's no use whacking high TP's in any tyre thinking they'll be faster,they won't,they'll only become more uncomfortabl,have a read at this article with regard to TP's:- https://janheine.wordpress.com/2016/03/ ... take-home/

[scottg]

On my '05 Kvale, Conti GranPrix 4000s, 28mm marked, 30mm actual size.

Just building up a Black Mountain Monster Cross, Compass 38mm.

"I laugh at your puny potholes"

[reohn2]

The Conti 28's arrived today and I fitted them in my lunch break.
There was 3mm between the tyre and the chainstay each side and I watched as the drizzle gradually cleared. By 4pm the road was showing a dry line so on with the gear and out for a test run. I know the road to my sons house down to the last second so off I went, pushing a bit as I didn't want to put in a slow time. Only a PB.

I was running 90 psi f & r and the ride was great. No more dodging man hole covers; straight over regardless, and so kind on the bum and the hands.

Soooooooooo pleased.

Cheers everyone
Paul G

The Luganos you removed are a bargain basement poor quality tyre,and the Conti's you've fitted aren't a premium quality item either,you'd find a quality tyre(see my previous post) much more comfortable.
Also 90psi is a lot of air in a 28mm(actual size) tyre unless you're a very heavy rider.

[Brucey]

the Maddux 3.0 rims are pretty skinny. I wouldn't fit a tyre over 28mm on those rims anyway and I certainly wouldn't expect to be able to run it at a lower pressures, because it will start to flop about and maybe even tuck under when you are cornering hard.

cheers

[reohn2]

the Maddux 3.0 rims are pretty skinny. I wouldn't fit a tyre over 28mm on those rims anyway and I certainly wouldn't expect to be able to run it at a lower pressures, because it will start to flop about and maybe even tuck under when you are cornering hard.

cheers

Even with 28s?

EDIT:-I've just checked the spec for these rims,they're 14.8mm hook to hook so possibly 17mm actual internal width.
I run a pair of DRC STouring rims with an internal width of 17mm(measured)with 35mm Hypers fitted @ 45psi front 65psi rear with an all up load(rider/bike/day luggage) of 98kg.I've ridden twisty descents @ 40mph + ridden rocky bridleways and other rough stuff without issue,in fact quite the opposite they're great combination and far more 'planted' and stable than 28s on the same rim,which I wouldn't have dare conteplate the same twisty descents at anywhere near the same speed.

[Brucey]

the Maddux 3.0 rims are pretty skinny. I wouldn't fit a tyre over 28mm on those rims anyway and I certainly wouldn't expect to be able to run it at a lower pressures, because it will start to flop about and maybe even tuck under when you are cornering hard.

cheers

Even with 28s?

I'd certainly be a bit leery of it; those rims are particularly skinny ('balloon on a stick' springs to mind when contemplating wider tyres...) and aggressive riding out of the saddle will soon start to push the tyre around. By all means the OP should try it (with care...) but I would expect that to soon become the limiting factor.

cheers