revchuck 

These would be a great choice, very low rolling resistance and tough enough. I'm using the 24mm version on 25mm HED Ardennes+ wheels and they measure just under 27mm wide; the 26s would be too wide for my bike (Ridley Fenix). You probably already know to check the clearance with wider wheels.

Dave Mayer

What?? No pro rides clinchers unless they are on a training ride, or it is a flat TT and their tire and wheel sponsors have a gun to their head.

On the Grand Tours, there wasn't a single rider on any stage on clinchers. Ditto with the classics.

A race with rough roads and climbing is bad terrain for clinchers. I would go with 22-23mm tubulars, due to their insurmountable weight advantage, and resistance to pinch flats. The only reason to go with heavier and less aero 25 and 28mm tires would be to add extra volume so that you can run lower pressures. The volume is only there to add protection against pinch flats. But since tubulars are basically impenetrable to pinch flats, you can ride lower pressures on smaller tires.

BTW: tubular tires are no better than clincher tires in terms of construction or rolling resistance. Clincher rims are the problem. The rims are heavy and fragile, solely because of the 2 'hooks' that hold on the clincher tire. The two hooks also cause pinch flats, and they are the reason why clinchers are scary dangerous to ride out if you have a sudden flat.

Doge

Well they kind-of are. Even with the exact same casing by the same mfg - like Vittoria - in the same size. I have that - clincher and tubular and also Veloflex. The clincher has material and air between the brake tracks. The bead is fixed. On a corner more of the side tread is used. The tubular, all the air is on top/outside the rim. The tire rolls a bit on the rim. Less tread is needed on the sidewalls in the same turn. Then the tubular has more usable, compressible air in the same size as the clincher, so on significant bumps there is less casing distortion.

I can put 22wide tread (Vittoria) on a 25 wide tubular and be fine for any debris-free cornering while I could not use that same patch on a clincher. Less rubber means lower rolling resistance. So for reasons of more compressible air and the option to use less rubber/case ratio the same exact tires do not need to exist.

That and the whole brake track you mention just makes the lighter setup the tubular one.
I don't really have high performance clinchers to compare but I know they tend to run about a 600g more a set than what I would select in a tubular. I grabbed this alloy clincher and the year raced (on chip seal, cobbles, all kinds of dry junk) tubular to illustrate the difference - both have skewers.

Tubular - thin tread, 25.5mm wide, 50mm profile ready to ride: 800g
FMB Record.jpg

Clincher - (shown below) less tube and tire: 980g
Alloy Clincher.jpg

Jeremy_S

Man don't stress this choice too much. I'm a good bit heavier than you but I live in DFW which is 100% chipseal and I ride here and in Carlsbad NM (work) which is also chip seal. I've ridden everything from Hutchinson Fusion 3's with regular tubes in 25's to GP4000's with latex tubes in 25's and currently Open Corsa CX 3's in 23 with Latex tubes. A good tire (Corsa or GP4k) is perfectly fine on chipseal. I don't have any stupid level of vibration, I don't die from it, and I don't pinch flat etc constantly and the roads here aren't the finest in the nation. Currently Corsa's have 1000 miles on them with nothing but Tx and NM roads and nary a flat and no issues with the roads and I run high pressure (I'm 216 with bike/gear) and either tire is perfectly acceptable on these roads. No need for 28's Cross etc. I take the road bike out one day and the cross bike the next and there is a difference but not mind altering and the road bike it just faster.

Dave Mayer

Good point: I missed this. On tubulars, the whole volume of air is on the outside of the rim, doing a useful job. On clinchers, there is an amount of air between the tire hooks (brake tracks), which does nothing in terms of smoothing your ride or protecting against impacts. Add another green tick to the tubular ledger.

Add to this: when you pressurize a clincher tire, the tire beads push out sideways against the rim. This is why clincher rims have inflation limits (tubulars don't), and why clincher rims have to be beefier than tubular equivalents. So on tubulars you can run a much rider range of pressures; lower due to the inherent resistance against pinch flats, or as high as the tire will take, as the inflation pressure does not stress the tubular rim.

HTupolev

You'll probably want to use much lower pressures. In addition to sometimes being uncomfortable over long rides, vibrating the bike isn't a great use of your forward momentum. Tire deformation does cause a loss in performance at lower pressures, but high-end supple tires substantially mitigate this.

Switching to 28mm might make sense, especially if your 25mm tires aren't width-matched to wide aero rims (you have less to lose). Just don't skimp on the tires if you do; switching from a great 25 to a bad 28 is pointless, because you'd have to run the tire stiff anyway to avoid excessive deformation losses. Then you'd have a heavier setup with no benefits.

I was curious about which particular tire models. Because...

...if your .5-1mph deficit was on really gnarly gravel tires, it's possible that with high-performance road tires you'd be just as fast on roads on your "gravel bike" as you are on your road bike. At which point considering racing it wouldn't be all that odd.

It would be nice to have research that targets and quantifies the comparison. It seems obvious that tubulars should do better on rough stuff at a given width than clinchers, but the only direct comparison I've seen (from a Bicycle Quarterly) showed the opposite happening; a tubular which had slightly outperformed a clincher on smooth roads wound up slightly underperforming on rough stuff. BQ was at a loss as to why; perhaps it has to do with losses at the particular rim/glue/tire interface, which has been implicated in having significant performance affects before.

Got

If you are going to race on such terrible roads, then get the widest tires you can fit on your bike from here and beat everyone in the race: https://www.compasscycle.com/product...ponents/tires/

I am running 1.25" (or 32mm) wide tires now and I would NEVER go any lower. I plan to upgrade to 2.0" wide tires in the future. Wider tires ARE faster. You guys talking about jumping from 25mm to 28mm have got to be joking. That is a minuscule jump and will hardly make a difference.

ThermionicScott 

What races have you won on them?

caloso

That picture of chip seal looks pretty good compared to the roads of VeloPromoStan. If that's what you're talking about 26mm will be fine. 28 will feel totally plush.

Jiggle

I'm you're exact weight. I ride exclusively on chip-seal roads. My current wheelsets are 31mm actual f/r @ 60/65psi. GP4000sII with latex tubes, other wheelset is 26mm/28mm actual S-works turbo at 70/75 psi, Vredstein latex on both sets.

Jiggle

The above statments are utterly nonsensical. They are so far off track they're off the road and bumping along in the cow pasture.

The only advantages tubulars have is the tire stays on the rim securely after a puncture and about 100g of rim weight. Every other conceivable metric is a negative for them.

Doge

Thanks for the visual. As my post was utterly nonsensical, can you show me yours - I'll spot you 200g (2x the 100g you mention).
1720g - 50mm profile, 25 wide, cassette, skewers, glued ready to ride. The ones used on cobbles were 100g more (as in the picture a few posts ago).
1720g M5.JPG

Doge

Love their roads. Learned the hard way one time.

Your area - I gave my camera to a follow car.

hack

Such a fun race ... loved getting through the bustling metropolis of Paskenta and hitting a cross tailwind this year. Usually, it's a 15 mile cross headwind and gutter fest.

Fiery

The majority of pro riders today ride 25 mm.

Tubulars resist pinch flats thanks to latex tubes they typically use. Tyre and rim geometry are less important factors. Guess what? You can get latex tubes for clinchers too.

Even if you don't flat the tyre, bottom out one too many times and your rim is toast, especially with carbon.

Fiery

Why do you think so? If actual, measured widths and heights of the mounted tyres are the same, the amount of air above the rim will be the same. Clincher will also have air between the sidewalls, but that's extra, it doesn't take anything from the air above.

Doge

If they were the same size, but in my Veloflex the clincher 25 measures smaller than the Tubular 25 of the same case. I had Vittoria too and did not measure. But while both road well (I road the Vittoria clincher on my front with a latex tube) the profile looked about the same as the 23 tubular. Vittoria uses the exact same made-in-Thailand stamped tread on both, and FMB did buy and use that tread (and I expect others).

But to my picture posted of the 1720g set https://www.bikeforums.net/19154969-post37.html- show me that for 2300g in a clincher. The whole system is heavier. The rims are heavier, add rim strip, tires and tubes and getting the equivalent air under there is going to cost about 600g/pair. Then in many cases you just don't have the same options in clinchers. I think the value best tire for this application is the Veloflex Vlaanderen which measures close 28mm but is not available in clincher. That the OP rider does not want to use tubulars is fine with me. I will ride clinchers this morning. Just that all nonsensical arguments aside - you cannot get the net result from a clincher wheelset you can from a tubular wheelset. I have posted mine. I have both.
Here is the 27 (measures 28 and is taller than expected) Veloflex Vlaanderen:
TarmacClearance.jpg

Doge

Yea - they do break. These are those same rims (the 1720g ones) where ridden cobbles, then over parking curbs (5" cement things) and finished the race - without flats on 25s.
BrokenM5s.jpg

Dave Mayer

Nope. The reason why tubulars are almost impenetrable to pinch flats is due to the rim profile. Look at a tubular rim from the front: it has rounded profile. No sharp edges. The clincher rim has two hooks that are (obviously) required to hold on the clincher tire bead. These hooks are sharp, hence the pinch flats. In addition, these hooks add weight at the worst possible place on a bike (rotating mass at extremities) and they are fragile.

Listen: the entire problem with clincher wheels comes down to these rim hooks. The extra weight, the fragility, the pinch flats, and blowout safety issues. If you could get rid of the hooks, you'd have a perfect rim profile. Which brings you directly to the tubular rim profile.

BTW: I was riding for the last 7 months on 22mm tubulars. Of this, at least a thousand miles was over packed gravel - not a single pinch flat. No flats at all actually, due to 20cc of Stan's sealant injected through the valve cores.

Fiery

Ah, so you were talking about open tubulars vs. the actual tubular version of the same model. I didn't get that at all from your original post.

I've no problems with your weight claims, nor indeed with tubulars in general. I didn't agree with what I interpreted as a general claim that clinchers intrinsically have less air volume above the rim than tubulars of the same measured width.

Fiery

I understand you love your tubulars and dislike clinchers, but you are still wrong about pinch flats.

Here's a tubular rim:


Here's a clincher rim:


It's the very top edges that pinch a tube, not the hooks and not the flat inside surfaces of the tubulars. The top edges have pretty much the same surface areas on both rim types. Pinch a butyl tube hard enough with any of these and the minor differences will not matter at all. Latex tubes is what makes all the difference - tubulars typically have them, clinchers typically don't.

Doge

I'm posting about the glue-on kind. Air is not between the brake tracks.
Often undefined in width discussion is what is stamped on the tire vs what they measure.
Below is a clincher - stamped 25, actual 24. I have stamped 23s that are this wide. My points were:
1 There are more high performance options in tubulars.
2 The same performance clincher wheelset has more mass than the tubular.

There are many reasons someone chooses one over the other. But I know of no case where the clincher wheel-set (everything) is as light as the equal performance tubular. That goes for track, road, MTB - and the world ITT.

A note on this pro comparison thing. They have a min weigh limit. They can choose where to add/put the weight. Some choose and like a flywheel feel. Some are paid to use things differently. Because Froome won the TdF on a Conti no more make the Conti the best climbing tire than Martin using clinchers. Until this year Sky used to buy FMBs. This year Conti is a sponsor - so they don't buy FMBs. IMO - the FMB is the better tire, but they can do fine without it.

Veloflex Corsa.jpg

Doge

Early 2015 we (racing kid, I buy) could not get our tubulars from our distributor. I had to use the wrong selection for about 3 month and junior got 4 flats. It was a miserable time and should have just gone clinchers - that was hind sight. I went direct to MFG and so far - 10K+ miles no flats since.

superdex

you're running your 25s too high. I'm 185-190 before the bike and I run 25mm tires in the low 80s psi.

to answer your question: keep the 25s. Run them at 80 psi, and enjoy the ride.


As an aside, is it a race or an organized/charity ride?

Doge

I'm thinking this is pretty obvious by now. There are no tubulars involved.