# Anyone gone large (28mm tyres)



## Huggis (8 Jan 2017)

I'm building a new road bike and can't decide whether to go for 25mm or 28mm rubber. I'm not an athlete by any stretch of the imagination, weight around 88kg. Wheels are Fulcrum Racing Quattro Carbon Disc. Roads around here are pretty poor and mainly consist of chip seal.

There seems to be a lot of contradicatory articles, some stating 28mm as having lower rolling resistance. Has anyone upsized and noticed any pros or cons?


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## smutchin (8 Jan 2017)

Wider tyres FTW. Much more comfortable and no noticeable effect on speed.

I have 25mm tyres on one road bike, but only because it doesn't have clearance for bigger.

I have 28mm tyres on my fixie, on which I did a 200km audax yesterday.

I have 28mm tyres on the other road bike but i plan to swap those for 32mm tyres at some point because it has the clearance for them.

I did LEJOG on a bike with 32mm tyres last September. Spent a lot of time in the company of some very quick riders.

The friend I rode with yesterday did it on a bike with 42mm tyres and it didn't seem to slow him down at all.

I can't think of any downsides. (ETA: assuming your bike has clearance for fatter tyres.)


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## Brandane (8 Jan 2017)

I am no athlete either, and no unrealistic aspirations to become one. I have 4 bikes but only one of them could be loosely described as a road bike; it's a Specialized Secteur. It came with 25 mm tyres as standard; but with the very odd exception, on any British roads I have ever ridden on, even 25's are uncomfortable (at pressures of between 80/100 psi). I now ride that bike on 28's and can't say I've ever noticed a difference in speed, but the gain in comfort is very obvious.
Two of my other bikes are steel framed, with 32 mm tyres, so I suppose it's fair to say I prefer comfort over speed. Bike number 4 is a MTB..


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## Huggis (8 Jan 2017)

Thanks. Yes the frame 'should' have clearance (KTM Revelator Sky). I say should as many tyres measure wider than they are


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## smutchin (8 Jan 2017)

User said:


> Potential clearance issues.



That's something you need to think of before upsizing on a particular bike but it's not a downside to actually using fatter tyres.


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## Lancsman (8 Jan 2017)

I have put 32mm on a Secteur, with shimano RS20 wheels it is the first time I have used wider tyres on a roadbike but I loved them no problems at all


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## MichaelW2 (8 Jan 2017)

Given identical construction and pressure, wider tyres have lower rolling resistance. They have higher air resistance and are heavier and lower max pressure. The faster you ride the more you gain from nzrrow tyres, but at lower speeds they dont have such advantage.


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## Fab Foodie (8 Jan 2017)

Yep, gone 28c on the Rourke and the fixie. My 80s Holdsworth is the only bike running 23c now -Michelin Pro Race... for summer days only :-)
On Oxfordshire's shitty roads, 28c make a lot of sense.


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## mjr (8 Jan 2017)

Remember, for years and years, the most common British road bike tyre was 27x1¼", which is 32mm wide (unless you're Schwalbe, for whom it's sometimes 28mm). It wasn't without some justification IMO. I'm still riding them


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## Dogtrousers (8 Jan 2017)

I sometimes ride 28s, sometimes 25s. I can't detect any difference.

However the 28s tend to clog up the mudguards with mud in winter due to reduced clearance. That's why I'm on 25s at the moment. Riding the 28s a teaspoon is an essential bit of kit for mudguard clearing.


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## Hedgemonkey (8 Jan 2017)

I went to 28mm awhile back, mainly due to the road conditions on my commute and now I wouldn't even go back to 25mm. Could be an age thing, but they seem to roll just as well and are far more comfortable.


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## Blue Hills (8 Jan 2017)

I'd go for 28, my standard tyre for round london's sometimes wonky roads. I think they are a good compromise. My main new favourite bike would have 32s on but i then realised that i can't get them on my rims - unless i'm being daft. So they will go on the sputnik equipped bombproof bike.
I did in a moment of madness buy two 25s, thinking i'd use them on the D Dynamo but fate taught me a lesson. I'd kept them a while. Setting up for the dd one exploded so i sold the other. I have been on country rides with some folk on narrower tyres and the trepidation with which some of them enter descents never fails to amuse me.
In any case i think there is some much quoted evidence that in most cases there is no speed penalty.


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## smutchin (8 Jan 2017)

User said:


> You might want wider still in Kent.



I live in Kent. I would opt for a minimum of 32mm on all my bikes if they had the clearance for it.


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## iandg (8 Jan 2017)

I switch between 25's and 28's on my road bikes. When my supply of 25's are worn out I'll stick with 28's


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## User482 (8 Jan 2017)

The brands vary considerably in their actual width. Michelin Pro 4s in 25mm measure nearly 28mm, for example.


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## Smokin Joe (8 Jan 2017)

Back in the day it was assumed that narrower was faster, hence Smokin Joe ending up with a pair of 18mm on his race bike. A few of his fillings had their lives shortened that season, where he also learned that 18mm tyres and greasy roads were not happy bedfellows.


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## I like Skol (8 Jan 2017)

Dogtrousers said:


> ...the 28s tend to clog up the mudguards with mud in winter due to reduced clearance. That's why I'm on 25s at the moment. Riding the 28s a teaspoon is an essential bit of kit for mudguard clearing.



Try adjusting your mudguards!

No reason to stop at 32mm. My commuter has Schwalbe 35mm tyres which are supposed to measure 37mm in real life and find these ideal for all and any trip's. Potholes are a mere inconvenience as I can crash through anything without fear, apart from being thrown from the bike or breaking the frame.....

All-road bike is currently on 28s but will probably go up a size or two if they fit


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## greekonabike (8 Jan 2017)

User said:


> You might want wider still in Kent.



I'm around the Whitstable, Canterbury area and the roads are ****. I see a lot of people running 28s. I've got 32s on the hybrid and had considered going to 28s but after a few weeks using the same roads regularly I decided against it. 

GOAB


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## 400bhp (8 Jan 2017)

MichaelW2 said:


> Given identical construction and pressure, wider tyres have lower rolling resistance.e.


Hmmm, not sure this is correct. Wider tyres = greater contact patch, ie greater rolling resistance?


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## Will Spin (8 Jan 2017)

Just put 28mm tubeless on mine, gone about 200 miles or so, better ride all round. Had to move the mudguards slightly to increase the clearance.


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## Dark46 (8 Jan 2017)

I use 25s at the moment but have used 28s on my road bike and really like them. You get a better ride and I think more grip too. If it wasn't for the fact that my mudguards are for 25s then I would go 28s next time. The only downside I found was in the wet they kicked up grit and deposited it on the forks and uprights


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## Supersuperleeds (8 Jan 2017)

I ride 28mm on the Tricross and 25mm on the road bike, I don't notice any difference between the two.


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## iandg (8 Jan 2017)

Got 40's on the Cross-Check and love them


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## 400bhp (8 Jan 2017)

User said:


> Wider but shorter.



Shorter?


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## boydj (8 Jan 2017)

I've gone to 28mm and like the results in terms of comfort and roadholding, with no impact on speed. However, I've done so on modern rims, which are a bit wider than the old standard, and give a good profile to the tyre. I'd stick to 25mm on older, narrower rims where a 28 would end up with a lightbulb profile.


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## smutchin (8 Jan 2017)

400bhp said:


> Wider tyres = greater contact patch



Not necessarily - size of contact patch depends on the tyre pressure. Although yes, one does generally run wider tyres at lower pressures .

What @User means by 'shorter' is that a skinny tyre will have a long, thin contact patch, while a wider tyre at the same pressure will have the same size (area) of contact patch but it will be closer to circular in shape. This means it will deform more easily over rough road surfaces, hence rolling resistance will be reduced.


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## 400bhp (8 Jan 2017)

User said:


> The contract patch, for a given tyre pressure and all up weight, will remain the same area so yes, wider will be shorter.



Cheers, understand.


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## HLaB (8 Jan 2017)

I have used 25mm tyre that actually came out over 27mm and I currently use 25mm and have previously used 22mm and 23mm tyres and can't say I've noticed much in the rolling resistance.


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## palinurus (9 Jan 2017)

Been using 28s for a long time, on 32s now (I've got lots of clearance on the commuter).

Still on 23s on one of my other bikes, but they're Duranos and they look and feel more like 25s if not even bigger. Never tried measuring them up tho'.


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## User482 (9 Jan 2017)

I like Skol said:


> Try adjusting your mudguards!


28mm tyres are a very tight fit under SKS 35mm guards IME. Wider guards are problematic in some frames.


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## Fab Foodie (9 Jan 2017)

boydj said:


> I've gone to 28mm and like the results in terms of comfort and roadholding, with no impact on speed. However, I've done so on modern rims, which are a bit wider than the old standard, and give a good profile to the tyre. I'd stick to 25mm on older, narrower rims where a 28 would end up with a lightbulb profile.


Agree it's a downside on narrow rims. I run my 28c on 23mm rims and the profile is peachy. I once put 28c on old narrow rims and they were a bit squirmy.


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## SpokeyDokey (9 Jan 2017)

Huggis said:


> I'm building a new road bike and can't decide whether to go for 25mm or 28mm rubber. I'm not an athlete by any stretch of the imagination, weight around 88kg. Wheels are Fulcrum Racing Quattro Carbon Disc. Roads around here are pretty poor and mainly consist of chip seal.
> 
> There seems to be a lot of contradicatory articles, some stating 28mm as having lower rolling resistance. Has anyone upsized and noticed any pros or cons?



Put as wide as you can on if you have clearance and the rim can take them.

Some of us have been riding with 28/32/35 for some time and a chubbier tyre (esp' 32/35) is way more comfortable than a 23 or even 25. Any 23/25 I have ever ridden has a bone jarring ride unless you are lucky enough to be able to always ride on super-smooth asphalt.

Up until early last year (?) or thereabouts the world was pro-skinny and everyone on chubby rubber was off base but now we are told that wider equals less rolling resistance (albeit they are generally heavier) the cycling fraternity is taking heed with its usual Lemming-like zeal and going wide.

I think some of the Pro's in the Paris-Roubaix were running 30mm last time around too.


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## Bonno (9 Jan 2017)

Smokin Joe said:


> Back in the day it was assumed that narrower was faster, hence Smokin Joe ending up with a pair of 18mm on his race bike. A few of his fillings had their lives shortened that season, where he also learned that 18mm tyres and greasy roads were not happy bedfellows.



Ha...I was of the same mindset back in the day, running 18mm's tyres and they of course had to be pumped up to at least 120psi !!
Learnt my lesson when i found a small patch of diesel at a bus stop and ended up with broken collarbone and stitches to head wound 
Changed back to massive 23mm's after that!

Some 30 years later i'm running 32's on my Racelight T... with psi down to about 80


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## mjr (9 Jan 2017)

I like Skol said:


> No reason to stop at 32mm. My commuter has Schwalbe 35mm tyres which are supposed to measure 37mm in real life and find these ideal for all and any trip's. Potholes are a mere inconvenience as I can crash through anything without fear, apart from being thrown from the bike or breaking the frame.....


My worst ever crash-where-I-sort-of-stayed-on-the-bike was blundering through a potcrater and being bruised on the backs of the thighs by the saddle as I rejoined the bike. That was on 28mm front, 35mm rear. Not even a pinch-flat from that. 

My current tyre width of choice for day-to-day riding is 37mm where they fit


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## Saluki (9 Jan 2017)

Hubs has 28mm tyres on his Whyte and that is his 'go to' bike in most circumstances. The carbon roadie gets left on the rack and he takes that Whyte flipping everywhere. He says that the tyres are more comfy.


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## andyoxon (10 Jan 2017)

28mm currently on my steel bike (previously 32mm), and 23 + guards on other bike (preferred to 25mm without guards). I have been experimenting with reducing tyre pressures and go for approx, 28mm: 75F/90R, 23mm: 85F:95R; for me this seems enough for good comfort & keeping potential pinch flats at bay.


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## e-rider (10 Jan 2017)

Huggis said:


> I'm building a new road bike and can't decide whether to go for 25mm or 28mm rubber. I'm not an athlete by any stretch of the imagination, weight around 88kg. Wheels are Fulcrum Racing Quattro Carbon Disc. Roads around here are pretty poor and mainly consist of chip seal.
> 
> There seems to be a lot of contradicatory articles, some stating 28mm as having lower rolling resistance. Has anyone upsized and noticed any pros or cons?


the evidence does indeed contradict itself - how can you have larger tyres that deform less under the same pressure hence leading to no increase in rolling resistance but at the same time provide a more comfortable ride?
The fact is larger tyres can be used at 'slightly' reduced pressures with no increased risk of pinch flats and also provide a slightly smoother ride - but lower the pressure will increase rolling resistance slightly and the larger tyre will be heavier, also slowing you down somewhat.
Pump a 25 or 28 up to 120psi and the evidence suggests no loss of speed as less tyre deformaton balances the small weight gain - however I can't see how you will gain comfort in the situation, perhaps just slightly more grip


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## Dogtrousers (10 Jan 2017)

Just out of interest, are these changes to "rolling resistance" something that one might actually notice, or is it akin to the difference between riding with water in your bottle vs riding with much denser and heavier orange squash.

In short - are you all talking cobblers or is this something that might actually make sense?


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## Ajax Bay (10 Jan 2017)

Dogtrousers said:


> are these changes to "rolling resistance" something that one might actually notice


I think that this in the region of 'marginal gains'. In the lab it amounts to (very roughly) an extra watt for each tyre for each 10psi less. But on the road this might or might not cancel out because the rider's body doesn't shake about so much (using and losing energy). And lower pressures equal a more comfortable ride. I've read elsewhere that carrying an extra 1kg over 'normal' terrain requires an additional 0.4w. So getting the tyre type, width and pressure 'right' could save a rider the same as losing 10kg of weight/baggage. Would you "actually notice" if you were carrying 10kg on the back, other than an alteration in bike handling? Recycling a post on another thread below.

This article is worth a read: I recommend it to you. The main argument is that by running wider tyres at lower pressures you reduce the suspension losses in the rider/bike combo and thus real rolling resistance is reduced. On a smooth drum (ie the rollingresistance.com tests) rollingresistance reduces very slightly as the pressure on the same tyre is increased - but this higher pressure results in more, for want of a better word, 'bouncing' on rough surfaces (eg roads) which actually means a narrower tyre at higher pressure (to avoid pinch flats) is 'slower'.

At higher speeds (eg 45+kph) aero aspects may come into play, and wider tyres tend to be heavier (which may be an issue if lots of acceleration involved - as opposed to steady riding). It would be good if tyre manufacturers of the good road tyres (Michelin, Continental, Vittoria, Schwalbe et al) made 28s which measured 28 and 32s in the same 'road tyre' range, as opposed to the step across (ie not up) to the fastest but heavier 'touring' tyres eg M Supremes. And frames were designed to cope with 32s, without getting too 'heavy' and 'gravel'.


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## smutchin (10 Jan 2017)

Ajax Bay said:


> the fastest but heavier 'touring' tyres eg M Supremes



Worth noting that Marathon Supremes in 32c are lighter than Duranos in 25c, and IME faster - Duranos are so stiff that you lose loads of speed on rough roads simply because you're juddering so badly - a good example of the 'suspension losses' you mention. Obviously there are much more supple options in 25mm that would be a lot more comfortable and have less rolling resistance than the Duranos.

The disc-brake version of the new Trek Domane comes with 32mm tyres as standard and that's definitely a dedicated road bike, not an 'adventure' or 'gravel' bike. Shame the non-disc version can only take 28mm tyres, but the limitation there is the brake callipers - you need brakes with a longer drop to fit larger tyres (especially if you want space for mudguards as well). But I think bike frame design is moving in the right direction in this regard - my Felt Z35 that I bought 8 years ago was sold as an 'endurance' bike but can only just fit 25mm tyres. That would be enough to put me right off the bike if I was in the market again now.


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## Ajax Bay (12 Jan 2017)

smutchin said:


> Worth noting that Marathon Supremes in 32c are lighter than Duranos in 25c, and IME faster


Not quite sure on that (the weight). In the http://www.bicyclerollingresistance.com/ tests the Duranos in 25 are shown as 240g and the Marathon Supremes in 37 are 440g. I'd be surprised if the latter were less than 350g in the 32mm version.
Nevertheless, according to the tests (see below) at, say 80psi, the Marathon Supremes in 37 do roll better than Duranos in 25, and that's in a lab! So much better when the rubber hits the tarmac. I still think there'd be a good market for the three road tyres (comparison below) if they made them in 32, for the increasing number of riders with frames that offer the clearances.
Compare/continental-grand-prix-4-season-2015-vs-michelin-pro-4-service-course-2014-vs-schwalbe-durano-2015
Compare/continental-sport-contact-2016-vs-schwalbe-marathon-supreme-2016-vs-vittoria-voyager-hyper-2016


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## dim (12 Jan 2017)

just to sidetrack and confirm ....

there's not much difference between 25mm tyres and 28mm tyres?

reason that I'm asking is because I'm on the market for another bike that I will use for commuting in winter as well as some solo Audax rides ... and with some of the bikes that I'm looking at, I doubt that 28's will fit, but 25's will be fine (no chance of 32's fitting)


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## smutchin (12 Jan 2017)

Ajax Bay said:


> Not quite sure on that (the weight). In the http://www.bicyclerollingresistance.com/ tests the Duranos in 25 are shown as 240g and the Marathon Supremes in 37 are 440g. I'd be surprised if the latter were less than 350g in the 32mm version.



I weighed them myself on my kitchen scales! I don't recall the precise numbers but the Duranos were definitely heavier.

It was a while ago, admittedly, so there may be some detail I've forgotten that explains the discrepancy.

ETA: just had a look at the Schwalbe site - they list Supremes in 32c at 380g, and Durano Plus in 25c at... 380g! So maybe it was the Durano Plus I had, though I could have sworn it was standard Duranos.


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## Ajax Bay (12 Jan 2017)

dim said:


> there's not much difference between 25mm tyres and 28mm tyres?
> . . . reason that I'm asking is because I'm on the market for another bike that I will use for commuting in winter as well as some solo Audax rides


Apart from the facile 3mm answer (NB tyre width quoted v actual has some variation qv but see rollingresistance.com for their tests) the difference is that you'll be able to run them about 15psi less. So more comfortable and minimal difference in rolling resistance. You'll see some very proficient audaxers on wider tyres (eg 32) eg the bloke who got round Mille Pennines (1005km) in about 61 hours (00:57 in video actually 40-622 measuring 38mm) - he's the one with grey hair in an 'upright' stance (link).

https://www.cyclechat.net/threads/n...-my-rights-to-return-them.202764/post-4334295
Extract (edited): Spurred on by @I like Skol's thought that " I don't think road bike sized tyres really stretch much between 60-120Psi."
I decided to test this by measuring the width of the new Continental GP 4 Seasons 28-622 I'd just mounted on 622-15 Mavic MA3 rims (NB 15mm inside bead, butyl inner) at pressures from 70psi to 110psi (max rating is 115psi).
psi width (mm)
70 25.6
80 25.8
90 25.95
100 26.1
110 26.2

Note that @andrew_s 's measurement on 13mm rims @ 100psi was 25.7mm.


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## dim (12 Jan 2017)

Ajax Bay said:


> Apart from the facile 3mm answer (NB tyre width quoted v actual has some variation qv but see rollingresistance.com for their tests) the difference is that you'll be able to run them about 15psi less. So more comfortable and minimal difference in rolling resistance. You'll see some very proficient audaxers on wider tyres (eg 32) eg the bloke who got round Mille Pennines (1005km) in about 61 hours (00:57 in video actually 40-622 measuring 38mm) - he's the one with grey hair in an 'upright' stance (link).
> 
> https://www.cyclechat.net/threads/n...-my-rights-to-return-them.202764/post-4334295
> Extract (edited): Spurred on by @I like Skol's thought that " I don't think road bike sized tyres really stretch much between 60-120Psi."
> ...


thanks for that .... I have bookmarked your post and will closer look tomorow


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## Milzy (12 Jan 2017)

28 tubs and average speed is up by 0.8mph.


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## Huggis (27 Apr 2017)

Hey all not sure if this thread is still alive. I posted earlier and ended up plumping for 28mm GP4000 for my Fulcrum Racing Quattro DB wheels. Now the interesting fact is that these measure nearer 31mm (30.5-30.7mm). The ETRO on the tyre are both 622 and the recommended tyre width is 28? However there is a bit of a 'light bulb' effect. I measured the 25mm GP4000 on my other bike and they came up at 26.5mm. Thinking about going down to the 25mm..


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## Flick of the Elbow (27 Apr 2017)

User482 said:


> The brands vary considerably in their actual width. Michelin Pro 4s in 25mm measure nearly 28mm, for example.


It also depends on the width of the rim. The same tyre on different rims could measure different widths.


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## keithmac (27 Apr 2017)

I run 700×35c at 35 psi wouldn't fancy anthing smaller than that, would knock my teeth out!.


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## Huggis (27 Apr 2017)

Flick of the Elbow said:


> It also depends on the width of the rim. The same tyre on different rims could measure different widths.



Yes but if both are ETRO 622 surely the width should be as specified? Can't think of any other area of cycling where such lose tolerances would be accepted.


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## fatjel (27 Apr 2017)

I recently swapped my Kaffenbacks frame for a London rd so I could get 35 tyres on 
Is a very definite comfort advantage over the 28s. (both marathon greenguards)


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## Ming the Merciless (27 Apr 2017)

Remember the old 27" x 1 1/4 inch tyres on your 10 speed Raleigh of the 80's? Well that's 32mm in modern money. Wider tyres are just back to the future...


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## Ajax Bay (28 Apr 2017)

Huggis said:


> but if both are ETRO 622 surely the width should be as specified? Can't think of any other area of cycling where such lose tolerances would be accepted.





Flick of the Elbow said:


> It also depends on the width of the rim. The same tyre on different rims could measure different widths.


622 is the diameter and rims will have a inner bead width shown. Tyres eg 622-25 will nominally measure 25mm wide but rim inner bead varies and that variation causes a difference in the actual tyre width (at the same pressure). It's not an issue of "lose (sic) tolerances", it's physical reality, as Flick has already said (though it's not 'could', it's 'will' (measure differently)).

https://www.cyclechat.net/threads/n...hts-to-return-them.202764/page-2#post-4334295
Measuring the width of the new Continental GP 4 Seasons 28-622 I'd just mounted on 622-15 Mavic MA3 rims (NB 15mm inside bead) @ 100psi was 26.1mm.
@andrew_s 's measurement on 13mm rims @ 100psi was 25.7mm.


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## Richard A Thackeray (28 Apr 2017)

I specified _28_s on my new (in March) bike
It's a Ribble CGR, so would look silly with anything narrower

My previous work/general purpose/'training' bike (which the CGR will supplant) was one of the Ribble 'blue winter/audax' frames, that would only accept _23_s with mudguards
The size still came as a shock, & felt dreadfully slow to begin with, allied to the higher (front end) position
It's a double-edged sword, as they're more pothole resistant, & also okay on dry bridleways (bigger air-chamber, for tree-roots)
That said, they're probably the biggest tyres I've used since (1.25") slicks on my Pace Research, back in the mid-90's!!

The 'Blue', & my (Ribble) Gran Fondo will both remain on _23_ though


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## Ajax Bay (28 Apr 2017)

Richard A Thackeray said:


> felt dreadfully slow


Can you quantify how much slower this bike with 28s on is compared to your 'blue' (say) on 23s?
Do you associate vibration frequency or amplitude with speed?


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## Foghat (28 Apr 2017)

Bearing in mind, of course, that Continental is pretty inept at maintaining consistency in applying its nominal tyre width figures to its tyres' actual physical dimensions.

See the following for an idea of the extent of variation, all on the same Mavic Open Pro rims:

GP4Season '28' - 26.3mm
GP4Season '32' - 32mm
GP4000 '25' - 27.5mm
GP4000S '28' - 31mm
Top Contact '28' - 24.5mm
Top Contact '32' - 27.5mm
Top Contact II '28' - 28.5mm
Top Contact II '32' - 31.5mm
Top Contact II Winter Premium '37' - 30.5mm

'28' seems to be particularly problematical for Continental's tyre-size-labelling supremo, with actual widths varying from 24.5mm to 31mm. This is absurd and completely unhelpful when you consider that (actual) 28mm is hovering around the optimum size for fitting the widest (sensibly) achievable tyres to 57mm-drop rim brake frames with mudguards (and many 49mm-drop brake frames without mudguards).


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## Richard A Thackeray (28 Apr 2017)

Ajax Bay said:


> Can you quantify how much slower this bike with 28s on is compared to your 'blue' (say) on 23s?
> Do you associate vibration frequency or amplitude with speed?


It had essentially the same gearing (barring a couple of lower sprockets) 
50/34 chainsets on 'blue' & CGR
12-25 on 'blue', & 12-28 on CGR

It was the drag factor, even at high pressures, may it was psychological, as it feels okay
Still slower uphill, but it is a lot heaver


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## smutchin (28 Apr 2017)

Richard A Thackeray said:


> It was the drag factor, even at high pressures, may it was psychological, as it feels okay
> Still slower uphill, but it is a lot heaver



Yeah, very possibly psychological. It's hard to quantify these things objectively as there are so many other factors to take into account. Personally, I don't find 28s noticeably slower than 25s.


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## Drago (28 Apr 2017)

28's on my Dolomite don't return notably different route times to the 23's on my F75. I would guess the aerodynamic effects of the mudguards make a much greater difference.


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## smutchin (28 Apr 2017)

YukonBoy said:


> Remember the old 27" x 1 1/4 inch tyres on your 10 speed Raleigh of the 80's? Well that's 32mm in modern money. Wider tyres are just back to the future...



TMN to... 



mjr said:


> Remember, for years and years, the most common British road bike tyre was 27x1¼", which is 32mm wide (unless you're Schwalbe, for whom it's sometimes 28mm). It wasn't without some justification IMO. I'm still riding them



I remember turning up to my first ride with a local club on a bike with 27 x 1 1/4 tyres and being treated with some scorn. That was around 10 years ago. I never rode with them again. They're probably all on 32mm tyres now.


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## Ajax Bay (28 Apr 2017)

Richard A Thackeray said:


> Still slower uphill


You didn't do the JK then?


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## Milkfloat (28 Apr 2017)

User said:


> A couple of hours ago a delivery driver brought a pair of 28mm Durano Plus round. They are now on the Planet X Holdsworth knock-off fixer ready for work next week.



I am going to be brave and will trying to fit 35mm vittoria voyager hyper's to mine tonight. I think it could be a step too far, but let's see.


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## Milkfloat (28 Apr 2017)

User said:


> Mine is with mudguards.



35mm rubbed before I even pumped them up, wheel totally jammed when at pressure. I doubt 32mm will fit either. I will have to stick to my 28s. The brakes are the problem, not the frame. This is without mudguards.


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## Richard A Thackeray (28 Apr 2017)

User said:


> A couple of hours ago a delivery driver brought a pair of 28mm Durano Plus round. They are now on the Planet X Holdsworth knock-off fixer ready for work next week.


That's what are on my CGR, the (28) RaceGuard Dual-Compound



Ajax Bay said:


> You didn't do the JK then?


The 'what'?


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## GuyBoden (29 Apr 2017)

Vittoria Randonneur 700x28, £13 at Decathlon.
https://www.decathlon.co.uk/700x28-randonneur-road-bike-tyre-id_8303019.html

Very comfy tyre at 28mm, with very, very good puncture resistance on the top tread, but have too thin side walls and extremely high rolling resistance. No punctures in this tyre in two years, but something could easily go through the side wall.

Interestingly, the Top Tread on the Vittoria Randonneur has a better puncture resistant score than the fabled Marathon Plus, but the side walls let it down. (Pun intended)
http://www.bicyclerollingresistance...arathon-plus-2015-vs-vittoria-randonneur-2015

Good, inexpensive tyre for an old man, such as myself, pootling around Cheshire country lanes.


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## Hopey (29 Apr 2017)

My bike (described as an "adventure road" bike came with 35s. Still use em, love em. Great for comfort on Edinburgh's pothold and cobble ridden streets. Thinking of downsizing to 32s or 28s when I replace the tyres. Any thoughts?


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## Huggis (29 Apr 2017)

So I just measured the 28mm GP4000 4 season on my touring bike - different rims but same spec (ETRO 622 - 17mm internal) and they come up at --- 27.7mm! vs 30.8mm on the other bike. So how can the same tyre from the same manufacturer come up so different!!!


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## Ajax Bay (30 Apr 2017)

GuyBoden said:


> Very comfy tyre at 28mm,


How do you quantify 'comfiness'? Is this not a function of the pressure you're running them at rather than the various make/type of tyre? Perhaps I've always been spoilt with my choices or don't realise what I'm missing.
I think, for this tyre, as you highlighted, it would be fair - as journalists don't say "this tyre doesn't roll well".
£13 not well spent. What width do the 28s actually measure? I note the 37 comes in at 33mm.
Clip from review (and I know you noted this in your post):

"Rolling resistance is very, very high. At the lower end of the air pressure range, rolling resistance skyrockets to over 50 watts per tire. That's more than 100 watts for a pair of tires, this will seriously slow you down. When using these tires, you should monitor air pressures very closely. Don't let these drop under 60 psi EVER."


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## Ajax Bay (30 Apr 2017)

Huggis said:


> So I just measured the 28mm GP4000 4 season on my touring bike - different rims but same spec (ETRO 622 - 17mm internal) and they come up at --- 27.7mm! vs 30.8mm on the other bike. So how can the same tyre from the same manufacturer come up so different!!!


Likely the internal bead width is not the same even if the rims are marked as such. Measure, twice.


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## I like Skol (30 Apr 2017)

I am running 32c Randonneurs on my best bike at the moment and I honestly think I am riding faster than ever so I don't understand where this idea that they have high drag comes from (unless I have suddenly developed absolutely awesome power)!


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## Ajax Bay (30 Apr 2017)

I like Skol said:


> I don't understand where this idea that they have high drag comes from


Drag is no difference but rolling resistance . . . Many people think this site is, if not the authority, then pretty good, for comparisons, so this is where 'it comes from':
http://www.bicyclerollingresistance.com/tour-reviews/vittoria-randonneur-2015


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## smutchin (30 Apr 2017)

RealDealWheel said:


> Still use em, love em. Great for comfort on Edinburgh's pothold and cobble ridden streets. Thinking of downsizing to 32s or 28s when I replace the tyres. Any thoughts?



My first thought is: why?

If you love them as they are, what do you hope to gain by changing?


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## Milzy (1 May 2017)

28 perfect for road racing. Even bigger for commuting. I'd never ride a 23 ever again.


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## Foghat (1 May 2017)

Huggis said:


> So I just measured the 28mm GP4000 4 season on my touring bike - different rims but same spec (ETRO 622 - 17mm internal) and they come up at --- 27.7mm! vs 30.8mm on the other bike. So how can the same tyre from the same manufacturer come up so different!!!



Wasn't your 30.8mm tyre a GP 4000? Presumably actually a GP 4000S II, unless bought a few years ago.......

This is a different tyre model to the GP 4-Season, and the two models suffer from the absurd inconsistency in Continental's width-labelling 'strategy', highlighted in my earlier post.

It's very unlikely that using different rims would create a 3.1mm difference in the same narrow tyre.


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## tincaman (1 May 2017)

I have taken my nice bike up to the maximum it will take with 30mm S-Ones and my commute bike with 40mm G-Ones. My average speeds per regular journeys haven't changed


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## BalkanExpress (1 May 2017)

Bonno said:


> Ha...I was of the same mindset back in the day, running 18mm's tyres and they of course had to be pumped up to at least 120psi !!
> Learnt my lesson when i found a small patch of diesel at a bus stop and ended up with broken collarbone and stitches to head wound
> Changed back to massive 23mm's after that!
> 
> Some 30 years later i'm running 32's on my Racelight T... with psi down to about 80



I was in a branch of Decathlon a couple of weeks back, the assistant could not understand why I needed a track pump that could reach more than 10 bar. I explained that I really only needed around 120-130 psi as it was for an old road bike, but, I I didn't want to have to kill myself getting to it. He started to edge away as if I was mad and said "No tyre needs that much pressure" as he made good his escape.


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