BoSoxYacht

large air volumes require very little pressure to hold the bead. It simply doesn't work at the low pressure used in cyclocross.

Jiggle

Except it is.

FrozenK

Everything I've seen so far suggests that, the people that I know that use tubeless for cross have to run 35psi or higher. But, again that is with non-tubeless tires. I think with proper tubeless tires and rims they will at least allow you to run the same pressures as tubed clincher but with lower rolling resistance.

BoSoxYacht

Wrong again Chuckles.

Jiggle

Time will tell Sunshine.

Ice41000

I like your posts and I appreciate knowledge and insight. Thnx.

Since at least half of my punctures (on the road bike) are pinch flats I moved to tubeless (Fulcrum 3 two way + Schwalbe One). I feel much more secure on fast downhills that way.
Yes, they are PIA to mount but I think it is worth it.

rpenmanparker 

Your choice, that's fine, but didn't you stop to wonder just for a second why you were pinch flatting so much? I understand you saw a solution and just decided to blow the tubed clinchers off and go tubeless. Makes perfect sense. But what about the fact that it isn't normal for tubed clinchers to pinch flat like that. There is a lesson in there somewhere if you would look for it: bad mounting technique (pinched tubes during mounting), insufficient pressure, bad riding technique, etc. I would have wanted to know why I was pinch flatting so much and had the option of fixing it without a change of tire type.

If, for example, the reason was bad riding technique (like lard-assing potholes), tubeless can prevent the pinch flats but won't protect your tires against cuts and rims against dings.

rpenmanparker 

Knee jerk response. Try understanding what is being said instead of just barreling ahead with the usual nonsense. Or possibly you were never surprised by esoterica on the 41 and thought to comment on that fact. Or maybe you never considered making a joke.

Sure there is Google. But why does that necessarily empower folks to post incomplete thoughts with little background to them as if all the knowledge available on the internet were suddenly implanted into everyone's brain? And when called on it, to react like it's not their responsibility that their writing was gibberish.

How hard is it to simply type, "Mical Dyck, a badass Canadian cross racer, just won her nationals on tubeless." Problem solved and a little knowledge imparted. Win-win.

Oh and thanks, Rob. I appreciate your response.

Jiggle

A child is angry because they were ignorant and they think it's my fault.

UnfilteredDregs

In other news 3 out of the top 10 "fastest" tires are tubeless:


Where the rubber meets the road: What makes cycling tires fast? - VeloNews.com

rpenmanparker 

The notion that the Specialized open tubular tire features un-vulcanized natural rubber in its final form is completely ridiculous and the VeloNews folks should know it. Uncured rubber is totally unsuitable as a construction material for a tire...any part of it. Yes, the processes for a tubular or open tubular and a clincher/tubeless clincher are likely to be different. Heat may be applied in a different way or at a different point in the process, but suggesting that a tire tread is made of uncured rubber is just plain wrong. Accelerating agents for curing rubber can also reduce the amount of heat needed, but that is not the same thing as saying the rubber is not vulcanized aka cured.

Furthermore if each tire were not individually optimized for Crr with regard to inflation pressure and those best Crrs for each tire compared, the test is meaningless. Perhaps a limiting range of pressures would have to be selected like 80-120 psi, but it is imperative that each tire be run at its best pressure for Crr within that range. Assuming all tires ought to be run at the same pressure to optimize Crr is absurd.

And if several examples of each tire were not tested with averaging and reporting of standard deviation, the test is irresponsible. You don't judge a product on the basis of one example.

Another half-baked experiment by incompetent, pretend scientists who are grossly ignorant of the topic they are reporting on.

UnfilteredDregs

In other words find the exact pressure that results in the lowest crr per tire, then compare. Makes sense if so, then a rider can choose brand/model/size dependent upon their weight and how they ride.

Psimet2001 

Wut? Dems all clinchers. I saw Zinn posted this on Facebook this morning and was going to read it but if they're all clinchers then what's the point...

Psimet2001 

I'm curious to see how the new Clements perform as well. I had a bit of a talk with Donn on the phone about them a couple of weeks back. The thing is, in general, with such a low air volume on a cross tire in order to keep any tire seated at the bead under cornering stress in cross as a tubeless you have to have one helluva stiff sidewall. Totally changes the tire reaction. Eliminates a lot of the reason running low pressure is used for.

Take a supple tubular at 19 psi and simply play with it - loading weight on it and seeing how the tire deforms, etc. Then do the same with a clincher/tubeless setup. Just not the same. Won't ever be until they figure out a way to "weld" that tire bead to the rim....oh wait....we did...we call it tubular.

2manybikes

Do they have a sponsor that makes gold underware? WTF?

rpenmanparker 

Actually plotting the Crr for each brand/model tire against pressure would show both where the minima occur and which tire has the lowest Crr at any pressure. It would allow a lot of choice. You could just buy the tire you like anyway and run it at its best Crr, choosing a tire based on it having the lowest possible Crr, or choosing a tire that offers the best compromise of comfort (pressure) and Crr, etc.

UnfilteredDregs

I see a bunch of "Open Tubulars," on the list...? Oh...wait...DOH!!!!!!!

rpenmanparker 

It is rather bizarre. Football shoulder pads? Gold underwear? WTF!

Shimagnolo

In the offroad 4wd world, they came up with the "beadlock" rim.
Can't wait to see those in cyclocross.

2manybikes

This is also my understanding of how tires are made. However, I bought a few "Forte" Performance Bike House brand clincher tires years ago, that were listed as not vulcanized. The rubber was very soft, and punctured easily. Maybe there is some other process for making tires? Beats me. I finally stopped using them, I pulled all sorts of stuff out of the tread after most rides.

2manybikes

I can understand the spikes on the helmet as just fun, but ....

FrozenK

Singlespeed World Championship. Things get weird.

79pmooney

I agree, the testing procedure wasn't perfect. But running the test say three times for each tire to optimize pressure? That's another probably half hour of testing per tire. Remember, this isn't a tire company with deep pockets funding this. This was two days of lab time as it is. "one example"? Two examples: read the article.

If you read the article, it becomes clear that the "vulcanized" tires have the tread applied in liquid form and cured into the tread. The "unvulcanized" tires have cured rubber tread glued onto the casing. The two casings thus behave quite differently. Also, if you read the article, you can see that the pressure matters little to the open tubular (and "unvulcanized") tires. Now, you are right, they probably should have spent the extra money for the lab time to narrow in on the best pressure for the "vulcanized" tires. (I put the word vulcanized in quotes because I believe the term actually app=lies to the early technology of rubber, 100 years ago and that it no longer applies; that what is done now is chemically different. I won't swear to this. It is something I read years ago.

My issue is with the testing weight, 60 kilos. At 155 pounds, I am not going to have more than 98 pounds on the rear tire, not the 132 tested. Do these results (and more important, trends) hold at 73% of the weight (in back), 60% in front?

"Another half-baked experiment by incompetent, pretend scientists who are grossly ignorant of the topic they are reporting on." No. An underfunded one? Yeah. We live in a world where spending real money for research that isn't done to refine or toot a company's own product is a rare event. If we, as buyers, pulled VeloNews off the stands like People magazine, we would have more grounds to gripe at VeloNews' limited budget.

Ben

Psimet2001 

When you win the SSWC you win the "Golden Speedo" as well as a free tattoo.

Turn down the volume if you're at work
Video from last year: https://vimeo.com/110743294
With it being in Louisville there's a TON of locals from here in that video. Mo Bruno Roy won last year - you see her at the end as well as throughout in her 5th Element homage costume. Lots of great people in that video.

Quick shot of Ellen S - she holds the record for most consecutive second place finishes ever. She noted that more than once as I drove her to Jingle Cross last year.

rpenmanparker 

A badly designed experiment is worse than no experiment at all. Incomplete results are worse than no results at all. Allowing for incorrect conclusions due to incomplete information is just wrong. If they are underfunded, they shouldn't be doing anything. IMO!

Actually testing fewer tires but doing it right would have been the better approach. They could have always come back with a follow up on more examples later on.

"Vulcanization" is still a correct term used for any chemical process used to cross-link any kind of rubber. The term was coined when heating natural rubber with sulfur was the only case known, but it has been broadened to apply to any rubber and any cross-linking chemistry. "Curing" is another equivalent term.