Punctures in pro races

[Cancellator]

I have noticed the large amount of punctures happening in races lately, especially in the one day races. I know that the cobbles, gravel etc. that are present increase the risk of punctures, but is tyre technology really unable to keep up?

Yes, puncture protection does add (some) weight, but is it really worth not having enough just for 100 grams? When a puncture can ruin your race. especially in the spring classics?

If these guys are running heavy duty tyres and the sharp objects on the routes are that bad, then maybe the roads should be cleaned up better?

 

[screaming fist]

It's not about weight but rolling resistance (and the watts a higher resistance costs)

 

[thehog]

I have noticed the large amount of punctures happening in races lately, especially in the one day races. I know that the cobbles, gravel etc. that are present increase the risk of punctures, but is tyre technology really unable to keep up?

Yes, puncture protection does add (some) weight, but is it really worth not having enough just for 100 grams? When a puncture can ruin your race. especially in the spring classics?

If these guys are running heavy duty tyres and the sharp objects on the routes are that bad, then maybe the roads should be cleaned up better?

The science is actually fascinating. I don’t think you’re going to see “street sweepers” out on a 250km route before a race so really it comes down to tire technology and the environment. What happens in early season races it’s that there’s still a “slick” of rain and dirt on most of the roads. Even when the roads are dry the slick remains then small particles be it rocks or debris from trees etc, stick to the tire and over a distance penetrate the walls of the tire.

In July and August when its barely rains in Europe the roads are crisp clean and you don’t see it as much. You also have to factor in that at the Tour almost every inch of road is immaculate. Reason for this is that each of the start / finish lines bid to have Tour pass though their town. They do this by submitting a road upgrade program as part of that bid. Often the roads are the smoother b1tchem rather than stones mixed down in tar that you see in other countries.

The second part is Pros like to use “singles” or tubeless tires because you have more control and way better rolling resistance. They feel great to ride on. Us mere mortals don’t use them as they’re a b*tch to change and we don’t have a support vehicle with 10 spares wheels in the back of the car. Regular Joes use tubed tires which are much stronger and heavier than singles. Singles are not as puncture resistance as the particle needs to break the tire and then the inner tube on regular tires. In Flanders and Roubaix you’ll see the use of tubed tires with a heavy tire sometimes up to 25c as a puncture can cost you 2 minutes if support vehicle traffic is heavy.

I don’t think you’re seeing more punctures. It does come down to weather and road conditions. Most Pros are on the same tire so I don’t think that would make much of a difference.

 

[spalco]

The second part is Pros like to use “singles” or tubeless tires because you have more control and way better rolling resistance.

Really? I thought they used tubulars.

Anyway, it really is kind of strange, that tires are basically unchanged since - what, 100 years? 150?

 

[thehog]

Really? I thought they used tubulars.

Anyway, it really is kind of strange, that tires are basically unchanged since - what, 100 years? 150?

Well the materials they use are a lot better than 100 years ago!

Another reason to use singles is when you do puncture you can keep riding. The tire is glued to the rim so when you get a flat the tire stays on the rim and you can at least keep moving and if a slow puncture you can keep a good speed whilst you wait for the support vechile. With a tubed tire no chance as the tire will roll off the rim as soon as the air has expelled from the tube and then you’re in trouble! Basically you fall off or the rim cracks and the wheel breaks along with several bones. Watch the next time a Pro flats. He’ll put his hand up, keeps rolling, radio in to the car, move to the back of the peloton, keeps riding then makes the change when the car arrives. No chance in doing that with a tubed tire.

Everyone remembers when Beloki crashed at the 2003 Tour. What happened was the glue on the tire melted and then rolled off the rim. That’s every riders worst fear. A bad mechanic or if you do a bad job yourself the tire can literally break free off the rim. That’s a death sentence if you’re going at 60km p/h downhill!

 

[gerundium]

Well the materials they use are a lot better than 100 years ago!

Another reason to use singles is when you do puncture you can keep riding. The tire is glued to the rim so when you get a flat the tire stays on the rim and you can at least keep moving and if a slow puncture you can keep a good speed whilst you wait for the support vechile. With a tubed tire no chance as the tire will roll off the rim as soon as the air has expelled from the tube and then you’re in trouble! Basically you fall off or the rim cracks and the wheel breaks along with several bones. Watch the next time a Pro flats. He’ll put his hand up, keeps rolling, radio in to the car, move to the back of the peloton, keeps riding then makes the change when the car arrives. No chance in doing that with a tubed tire.

Everyone remembers when Beloki crashed at the 2003 Tour. What happened was the glue on the tire melted and then rolled off the rim. That’s every riders worst fear. A bad mechanic or if you do a bad job yourself the tire can literally break free off the rim. That’s a death sentence if you’re going at 60km p/h downhill!

i thought he lost it because he hit a patch of molten asphalt?

 

[thehog]

i thought he lost it because he hit a patch of molten asphalt?

He did but because of the heat the glue that sticks the tire to the rim had melted and rolled off.

The YouTube doesn't really show it but look at the back tire as he rides through the hot patch.

http://m.youtube.com/watch?v=Gr89ku-K2WU

 

[happychappy]

Really? I thought they used tubulars.

They absolutely do use tubs.

 

[danjo007]

i thought he lost it because he hit a patch of molten asphalt?

nope, the tyre rolled off the rim. unless you can fly, you are going to get hurt big time.

 

[karlboss]

Singles are a different name for tubulars.
Lower rolling resistance...nope. A magazine supported by continental tested clinchers vs tubs for rolling resistence, and some other things, for an 85kg rider, at 35 kph.
Best clincher, 109psi 25 Watts resistence 130psi 23.2 watts

Best Tub, 109psi 34.6 watts 130 psi 33.2 Watts
Now if we assuming linearity 1 PSI increase lower rolling resisteence by .07Watts. The pressure would need to be 241 PSI before equaling the clincher at 109 PSI. If this number isn't ridiculous enough, remember that in fact that relationship isn't linear.

For reference a Continental tyre top scored over all, however the lowest resistance clincher was a veloflex, and tub vittoria.

 

[RDV4ROUBAIX]

The issue of rolling resistance between clinchers and tubulars is zero. Pro racers and many amateurs use tubulars for other reasons, weight, safety, ability to run a wider range of pressures, not what this thread is about anyway.

Punctures are a freak thing no matter if it's the Classics or the Tours. There are some editions of even Roubaix where hardly anyone sees a spare wheel, some years it's mad chaos with tons of riders standing beside the road holding their puncture in the air. Adding weight to the tire for more puncture protection isn't an option, add 100g to a tire and it's basically a commuter tire. Rotational weight is a big cookie because the weight at the outer circumference of the wheel is X2 when in motion, 100g turns into 200g when you get up to speed. At most some riders will fill their tubulars with sealant commonly used for tubeless, adds very little weight, and this has been going on since the 60's, maybe before.

 

[thehog]

Well the materials they use are a lot better than 100 years ago!

Another reason to use singles is when you do puncture you can keep riding. The tire is glued to the rim so when you get a flat the tire stays on the rim and you can at least keep moving and if a slow puncture you can keep a good speed whilst you wait for the support vechile. With a tubed tire no chance as the tire will roll off the rim as soon as the air has expelled from the tube and then you’re in trouble! Basically you fall off or the rim cracks and the wheel breaks along with several bones. Watch the next time a Pro flats. He’ll put his hand up, keeps rolling, radio in to the car, move to the back of the peloton, keeps riding then makes the change when the car arrives. No chance in doing that with a tub

Thanks Hog your insights are most interesting. It's like I'm in the peloton reading your posts.

 

[Martin318is]

In the case of Beloki, yes the tyre came off the rim and that was partly due to poor fitting and/or heat of the rim glue, but, the thing that actually pulled the tyre off the rim was the patch of molten (and therefore more sticky tar) that he hit at an angle under braking. It was a combination of the two factors rather than any one on its own.

An example of a bad fit was the Neil Stephens crash during a TdF breakaway on basically flat ground as he went through a roundabout. As he continued the turn and was about to straighten up to exit, his rear rolled off and made him slide sideways into street furniture. He got a major yelling back at base for suggesting it was the mechanics fault apparently.

 

[Michele]

They do use tubular, no one of the main teams use tubeless.

One of the reason you see more punctures is cause for avoid pave, for example, they ride along the road where the surface is more dirty and easier to get a puncture.

 

[JayKosta]

Tubulars - how they are made.
A tubular tire has a regular inner-tube with its own valve.
The inner-tube is completely contained within the exterior of the tire.
The casing of the tire is sewn tightly closed around the inner-tube with the seam running against the middle of the rim's concave outer diameter.
There is an additional piece of fabric sewn over the seam as a glueing surface.

To repair a pucture in the inner-tube it is necessary to cut open a small portion of the sewn area so the tube can be pulled out and patched.
Then the tube is pushed back into place and the casing re-sewn - without making a new puncture with the needle, and without making the seam too bumpy.
And without getting too much blood on the tire from poking your fingers with the needle.

Jay Kosta
Endwell NY USA

 

[nevada]

I've had ex pro wheels with tubs on and spent hours getting them off. Beloki's issue could have been a number of reasons but theyre usually stuck on super well.

 

[thehog]

It's amateur hour on this thread. Not until you've ridden singles do you knows they're 10,000 times better than clinchers. No Pro in their right mind would ride clinchers. Ever. Maybe Roubaix only.

 

[Leopejo]

A newspaper observed that punctures seem to target two teams more than others, that is, Radioshack-Leopard-Nissan (Cancellara, Bennati) and Farnese Vini (Gatto in Strade Bianche and in two Belgian semiclassics this year). Both teams have the same supplier.

 

[Wallace]

I've had ex pro wheels with tubs on and spent hours getting them off. Beloki's issue could have been a number of reasons but theyre usually stuck on super well.

The day was super hot--so hot the asphalt was melting. In that kind of weather, and with the rims heating up from braking on a long switch-backed descent, tubular glue can become unstable. Beloki was taking crazy risks trying to catch Vinokourov who was up the road and who Beloki saw as a real threat to his Tour chances. Rolling a tire on a curve was one of those risks.

 

[Cancellator]

A newspaper observed that punctures seem to target two teams more than others, that is, Radioshack-Leopard-Nissan (Cancellara, Bennati) and Farnese Vini (Gatto in Strade Bianche and in two Belgian semiclassics this year). Both teams have the same supplier.

Now that sounds interesting. They have Schwalbe tyres right?

 

[karlboss]

It's amateur hour on this thread. Not until you've ridden singles do you knows they're 10,000 times better than clinchers. No Pro in their right mind would ride clinchers. Ever. Maybe Roubaix only.

For which race? Martin won the world ITT on clinchers.

But in general I agree, you never see it for anyone of a combination that RDV already mentioned, as to why there are more punctures these days...I don't think there are. There are good days and bad days, but it all seems consistent. Maybe way back when riding a tyre that was 100g heavier there weren't so many, but for the past 10 or so I haven't really noticed an increase, if anyone has stats to prove me wrong, I may rethink that position.

 

[Cancellator]

But in general I agree, you never see it for anyone of a combination that RDV already mentioned, as to why there are more punctures these days...I don't think there are. There are good days and bad days, but it all seems consistent.

My question was not why there are more punctures now than in the past, I don't think there are. I was wondering if there is nothing they can do to reduce them, with the advance of technology.

 

[Leopejo]

Now that sounds interesting. They have Schwalbe tyres right?

Yes, Schwalbe. The magazine that wrote about this is Italian Gazzetta dello Sport (Giro, etc. organizers).

 

[karlboss]

My question was not why there are more punctures now than in the past, I don't think there are. I was wondering if there is nothing they can do to reduce them, with the advance of technology.

They already put a layer of kevlar in, I suppose they could use vectran, be surprised if none do, RDV any ideas? I think tyre manufacturers do as much as they can remembering that everything is a compromise.

EDIT, could be possible to do away with tyres, and ride rubber coated carbon hoops or something