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Some Recent Crr Tests
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TOPIC: Some Recent Crr Tests

Re: Some Recent Crr Tests 6 years, 3 months ago #26744

  • kraig
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yerp wrote:
<snip>...unfortunately censorship at Slowtwitch by the moderators is a little out of control. Although explained to me in a much more conspicuous way, they apparently are not a big fan of usedzipp.com *surprise* *surprise* and chose to restrict my account because of it. But that is an entirely different topic.


what did you do to get your access on the website you mention restricted?

FWIW, I think you are way ahead of anyone else out there on the internets regarding this topic you bring up - please keep us informed. Chapeau, to you sir!

A few questions, though, since you have piqued my curiosity regarding your observations and your website.

How do you think the observations you mention in this thread will affect the resale value of used zipp clinchers that are currently on the market? Do you discuss the findings you have mentioned in this thread on your website? If not, why not?

Do you think that the observations you have reported in this thread sway things when it comes to the whole "tubular vs clincher" debate?

Also, since I've got your attention...I've got a zipp clincher 1080 from a couple years ago, how much should I expect to get for it on ebay when/if I put it up for sale?

TIA,
-k
-kraig

Re: Some Recent Crr Tests 6 years, 3 months ago #26745

Kraig,

Like all ST bans that take place it is a result of conflict of interests that ST has with advertisers/sponsors. Honestly the mods at ST remind me of the Soup Nazi episode from Seinfield. It is a great place for discussion, but they way they approach discussion amounts to nothing more than pure censorship in favor of their advertisers/sponsors. I would rather not drive traffic to ST if I can avoid doing so. It is a shame as there have been many other bans on the site including the producer of Tririg.com and Flo wheels, and the departure of Dr. Andrew Coggan. Unfortunately the bans of certain people are just noise in the ST juggernaut until someday when they are asleep at the wheel and someone creates a better forum and can attract the right names to participate in discussion.

Anyways, back to your other questions. Well honestly I think Zipp and Hed have potentially liability on their hands. It is funny because I was just reading an article in a triathlete mag about the Zipp 404 CC and the writer wrote about how easy the tires are to get on and off the new rims and how triathletes don't need to worry about flats anymore. On the contrary this "feature" is actually not a benefit to the user at all. I would rather have the tire be a little harder to put on and off rather than have it blow off while I bombing down a descent. And secondly, many tires are so loose that once you get the first bead on, then the bead falls off again as you work on the second bead. This makes quick tire change difficult, and I find the quick burst of air from C02 often cause the tires not to be centered well and causes instant blowouts.

As for me, I switched to Zipp carbon clinchers because the aerodynamics of the wheels are supposed to be the same as the tubular version and I could get better rolling resistance and ease of flat change with the clinchers. Unfortunately the blow-offs have had me searching ebay for Zipp tubulars again. Although I have been searching I will probably stick with the clinchers for the time being and run a Continental 4000s on the rear. I know I am giving up something, but the R4 aero is just too susceptible to casing cuts from my personal experience. As for general economics I don't think it will affect the value much of carbon clinchers. The average user will never be aware of the incompatibility issue of certain open tubulars with wide rims. I do think this tilts things back in favor of tubulars quite a bit though.

As for your 1080 - there still seems to be some general interest for the wheel. I would throw it up on ebay if I were you. I was thinking about adding a "For Sale" section up on Usedzipp.com. I would be more than happy to make a trade and put your wheel up there for some of your data reports

Re: Some Recent Crr Tests 6 years, 3 months ago #26746

  • kraig
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Like all ST bans that take place it is a result of conflict of interests that ST has with advertisers/sponsors.


This can often times be a bit of a gray area...one that is subject to interpretation. What, specifically, did you do to get restricted access?

I'd really encourage you to share your findings on your website, since it appears you haven't done so? Just stick to the facts of your tests and eliminate any speculation such as what you mention previously (regarding liability and whatnot - I don't really have an opinion on that, but I'd assume their clincher rim design meets the dimensional specs put forth by the various governing bodies). I think posting your findings on your own site would really lend weight to your observations. Let me know how I can help drive traffic to your write-up. Your tests sound very intriguing!

For the record, historically, it's been my experience that zipp product is a total pain in the ass to mount tires on - though, my recollection of mounting several open style tires on their carbon clinchers during tunnel tests here in SD more recently is a bit fuzzy...meaning that the carbon clincher installation process on those wheels was probably less of a pain in the ass than previous zipp designs but not out of the ordinary. Take that info FWIW!

cheers,
-k
-kraig

Re: Some Recent Crr Tests 6 years, 3 months ago #26747

I'm not sure usedzipp.com is where I want to put it but I am working on tri blog that it might be more appropriate for. I'll come up with something but I want to take some more video of the tires blowing off and do some more testing during a few hot days in the upcoming week.

As for the rim spec, well I am sure the rim spec meets the guidelines. I have done a lot of research on this subject and with tolerances Zipp use to always err towards the wider end of the spectrum. With the new CC I am not sure how they are built but I would guess on the conservative side as well, but all I can tell you is the tires slip on and off very easily. I have never had to use a tire iron with any of the tires that were either new or used. As for liability I find it interesting that Zipp did all their testing with the wheel in a water chamber and pumped the tubes up with water as well. I am not sure you are going to get the affects of a hot tire that becomes extremely mailable in a water tank. Sure they might have been able to withstand high pressures but that may not be representative of real world testing.

As for ST, I believe Jordan put the ban in after I changed my handle to electusunus ==> usedzipp.com. I got some emails from Jordan that said they didn't want to be associated with usedzipp.com. It was clear from discussions that Jordan had been talking to Zipp about it. Believe me I was a long-time lurker on ST - the place is full of censorship.

Honestly there is no reason BTR couldn't be a better resource than ST. Get a few of the heavy hitters like Tom A, Jackmott over here. 90% of the discussion seems to always be about the bike anyway with little to talk about in regard to swim/run

Re: Some Recent Crr Tests 6 years, 3 months ago #26750

  • kraig
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I'm not sure usedzipp.com is where I want to put it


I think it is the most appropriate place for you to put it.

As for the rim spec, well I am sure the rim spec meets the guidelines.


sounds like if you are sure the spec meets dimensional requirements, the bone to pick is with the tire guys, no?

I have done a lot of research on this subject and with tolerances Zipp use to always err towards the wider end of the spectrum. With the new CC I am not sure how they are built but I would guess on the conservative side as well, but all I can tell you is the tires slip on and off very easily. I have never had to use a tire iron with any of the tires that were either new or used.


tire installation ease may not have a whole lot to do with it - I think if you search the archives here I posted some info about this.


As for liability I find it interesting that Zipp did all their testing with the wheel in a water chamber and pumped the tubes up with water as well. I am not sure you are going to get the affects of a hot tire that becomes extremely mailable in a water tank. Sure they might have been able to withstand high pressures but that may not be representative of real world testing.


how hot is the tire getting during this test:

cdn.mos.bikeradar.com/images/bikes-and-g...ls-500-90-500-70.jpg

As for ST, I believe Jordan put the ban in after I changed my handle to electusunus ==> usedzipp.com. I got some emails from Jordan that said they didn't want to be associated with usedzipp.com. It was clear from discussions that Jordan had been talking to Zipp about it. Believe me I was a long-time lurker on ST - the place is full of censorship.


sounds like there's more to the story.

Honestly there is no reason BTR couldn't be a better resource than ST.


experts all around the internets use BTR as a resource.
-kraig

Re: Some Recent Crr Tests 6 years, 3 months ago #26751

kraig wrote:
I'm not sure usedzipp.com is where I want to put it


I think it is the most appropriate place for you to put it.

As for the rim spec, well I am sure the rim spec meets the guidelines.


sounds like if you are sure the spec meets dimensional requirements, the bone to pick is with the tire guys, no?

I have done a lot of research on this subject and with tolerances Zipp use to always err towards the wider end of the spectrum. With the new CC I am not sure how they are built but I would guess on the conservative side as well, but all I can tell you is the tires slip on and off very easily. I have never had to use a tire iron with any of the tires that were either new or used.


tire installation ease may not have a whole lot to do with it - I think if you search the archives here I posted some info about this.


As for liability I find it interesting that Zipp did all their testing with the wheel in a water chamber and pumped the tubes up with water as well. I am not sure you are going to get the affects of a hot tire that becomes extremely mailable in a water tank. Sure they might have been able to withstand high pressures but that may not be representative of real world testing.


how hot is the tire getting during this test:

cdn.mos.bikeradar.com/images/bikes-and-g...ls-500-90-500-70.jpg

As for ST, I believe Jordan put the ban in after I changed my handle to electusunus ==> usedzipp.com. I got some emails from Jordan that said they didn't want to be associated with usedzipp.com. It was clear from discussions that Jordan had been talking to Zipp about it. Believe me I was a long-time lurker on ST - the place is full of censorship.


sounds like there's more to the story.

Honestly there is no reason BTR couldn't be a better resource than ST.


experts all around the internets use BTR as a resource.


The tire guys might be part of the problem but it is more of the design of the Open Clinchers which I think is a problem. Maybe with the old narrower rims the light bulb effect would end up putting more pressure on the bead to stay in place. Part of the problem though seems to be the heat of the tire. It is really an interesting thing when you put out the tire in 95+ degree heat in the radiating sun - the tire becomes extremely warm and soft. I have had them out on cloudy days and it doesn't seem to gather any heat.

As for ST I think there is less to the issue. Don't get me wrong I think ST is a wonderful resource that is made by the community, but it is moderated in a way that is not always transparent in regards to their interests and is moderated too heavily. Unfortunately there is too much going on @ ST and usually the moderation gets lost in the noise. It is a shame and it is this sort of arrogance that has been the demise of many businesses over the last century. ST is made up of the community and the community is sold as a product to their advertisers. If the community finds a more popular hangout then ST is done. Unfortunately even when there is a backlash the fire is usually quickly covered and with both Dan and Jordan's ties to the rest of triathlon, USAT, WTC, I think people really hesitate to speak their minds as they are scared into submission. As for me, I'm not afraid to speak my mind. If ST doesn't want me around that is fine, I will do my best to move the discussion somewhere else.

Re: Some Recent Crr Tests 6 years, 3 months ago #26752

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zipp wrote:

The tire guys might be part of the problem but it is more of the design of the Open Clinchers which I think is a problem.


You'll have to clarify this for me, as I don't understand what you are intending to say here. As I read the above, it sounds like you are in the "it's a tire problem" camp...before this statement, I was under the impression you were in the "it's a wheel problem" camp.

Maybe with the old narrower rims the light bulb effect would end up putting more pressure on the bead to stay in place.


It might be worth your while to purchase a copy of the ISO clincher design specification. And, then, see how the wheel samples you are using relate to that spec.

It might also be worth your while to consider convective heat transfer for your future testing (this might make your tests more real-world). You've tested multiple samples of the same tire model, right?

As for ST I think there is less to the issue.


anytime someone mentions private email exchanges, I'm open to the possibility of mis-interpretation. We'll have to agree to disagree that there is more to the story.

I agree that transparency is key - this is in part why I think you should post your tests on your monetized website that only exists because of zipp product.
-kraig

Re: Some Recent Crr Tests 6 years, 3 months ago #26753

To be clear. I believe the problem lies with Open Tubulars on wide rims. I have tried different tires and all Open Tubulars products I have tried have failed. On the flip side, every non-open tubular has held up just fine.

Re: Some Recent Crr Tests 6 years, 3 months ago #26755

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To be clear. I believe the problem lies with Open Tubulars on wide rims.


Thanks for the additional information. As you've described above, your claim is that there is an interaction effect taking place here. IOW, an ISO conforming rim and an ISO conforming tire, when used in combination (within ISO limits for tire/rim size combinations) becomes an unusable system.

Sounds like you've got your work cut out for you in terms of validating your claim.

Please keep us updated on your progress,
-kraig

Re: Some Recent Crr Tests 5 years, 5 months ago #26982

This is an impressive amount of information. I would be interested in knowing more about the methods used to collect it so I could compare the results. Where can I look?

Re: Some Recent Crr Tests 5 years, 5 months ago #26983

  • kraig
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vernonforbes wrote:
<snip> Where can I look?


comparing across test methods/apparatus can be hit and miss. I've found it best to do comparative testing with the actual equipment being evaluated. Within a tire brand/model, there can be significant variation even with the same methods/apparatus (i.e, sample to sample variation).

The forum probably has all the details over the years for Al's protocol. A search of the archive may prove more useful than what I'm about to write:

in a nutshell, Al uses rollers and a fork stand (that constrains all 3 components of translation, and 2 out of the 3 rotations about the front dropouts...rotation about the axle is left free). Rear wheel is supported between two rollers (two contact points). Some details about the rollers are included on the results pdf.

I do believe Al corrects results using ambient air temperature taken prior to testing. A search of the archives here will probably give more details on this.

Roller to flat surface corrections use theory developed in the book Bicycling Science - I think Whitt and Wilson are the authors of that - I'd suggest researching that online, as there are probably links to spreadsheets already made that implement the equations (probably even a link here on the forum to the spreadsheet and background referenced by Al on the results pdf).

more tidbits are on the results pdf, which I'm thinking you've already inspected?

hope this helps.

-k
-kraig

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