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2009 Men's World Time Trial - Tire Choice
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TOPIC: 2009 Men's World Time Trial - Tire Choice

2009 Men's World Time Trial - Tire Choice 8 years, 2 months ago #25410

  • AFM
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Sorry about bringing this up again but .....

Making many assumptions and using previous observations I looked at tire choices and how they may have affected the men’s World TT results held on 9/24. Cancellara and Larsson both are from Saxo which is sponsored by Specialized. I haven’t tested the Specialized tubulars but one closet tester has done so and found that with 3/2 coats of Mastik One that they are essentially equal in Crr to the Bonty RXL Pro. So let’s say that both of them were on some of the fastest tires available.

Tom Zirbel rides for Bissel although he is moving over to Garmin next year. Bissel is sponsored by Vredestein. I tested a Vred Tricomp tubular a few years ago that was professionally mounted to a race wheel probably by the same mechanic from whom I learned about the 3/2 gluing process (although that’s really been around for many years). The Crr on that tire was ~0.0032. Assuming that is representative of the newer Vred’s and that Zirbel used those tires plus equal aero performance of the RXL Pro tubular, Tom would have been ~ 40 sec faster on the day and would have been on the podium in 3rd place. Who knows though – he might have been using a set of Garmin wheels/tires – I know that JV (the other one) is up to speed on Crr and aerodynamics.

Tony Martin rides for Columbia who is sponsored by Continental. I tested a Conti tubular from Team BMC a few weeks ago – the Crr was ~ 0.0033. Assuming that the Crr of that tire is representative of what Martin rode in the TT (although he might have had a more narrow tire ??) and again equal aerodynamics he would have been ~ 45 sec faster on an RXL Pro but would not have moved up into second.

Many assumptions here but if those assumptions are fairly accurate it’s really tragic that because of tire choice Tom Zirbel in his first ever bike race in Europe might have been on the podium in the World Time Trial Championship especially after completely selling out and getting sick on the course. That would have meant that Tony Martin would have lost his podium spot due to slow rolling tires – equally unfortunate.

Great to see DMC lounging in the “finisher’s podium” tent conversing with Zirbel. Great race to finish 11th in the World. Love to hear some details on equipment and race.

Re: 2009 Men's World Time Trial - Tire Choice 8 years, 2 months ago #25414

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Nice observations and very interesting to see their tire choices.

However I was thinking that maybe the higher tire pressures they probably use reduce the rolling resistance for all tires and thereby also the difference between best and worse.

Also I have a feeling that they are either on rebagded tires or prototypes/special versions. I meen it's hard to believe that people using all of their time and efforts on racing don't pay enough attention to details like this, but then again you newer know.

Re: 2009 Men's World Time Trial - Tire Choice 8 years, 2 months ago #25417

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Looks like Vredstein to me:

Re: 2009 Men's World Time Trial - Tire Choice 8 years, 2 months ago #25418

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tcramer wrote:
However I was thinking that maybe the higher tire pressures they probably use reduce the rolling resistance for all tires and thereby also the difference between best and worse.


On the other hand Kraig recommends a +15% boost of AFM values on real road surfaces, compensating a greater tire pressure.

Re: 2009 Men's World Time Trial - Tire Choice 8 years, 2 months ago #25419

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tcramer wrote:
Nice observations and very interesting to see their tire choices.

However I was thinking that maybe the higher tire pressures they probably use reduce the rolling resistance for all tires and thereby also the difference between best and worse.

Also I have a feeling that they are either on rebagded tires or prototypes/special versions. I meen it's hard to believe that people using all of their time and efforts on racing don't pay enough attention to details like this, but then again you newer know.


Just took a very quick look at some of the smooth roller data that I have for different pressures on the same tire and there doesn't seem to be much change in Crr difference between 120 psig and 150 psig, i.e. if a particular tire has a Crr 10% less than another at 120 psig the difference at 150 psig is ~ 10%.

But a good point in that I have no idea of what pressures the respective riders used in their tires. Also it's possible to use too much pressure and actually lose speed on bumpy real roads - Tom Anhalt did some nice testing showing that using the VE method developed by Robert Chung for a particular set of conditions. I guess that my guess work IMO D with the assumptions identified is that if Tom Zirbel had been using the RXL Pro tubular at the same pressure that he raced at he would have been on the podium.

Dan (thanks Dan) posted the picture of Zirbel using what looks to be the Vred tubulars - the label looks authentic - the only rebadged tire I've personnally seen was the tire used by Discovery/Astana which had a very simple Hutchinson label on the side casing - no width, pressure range, model, etc. I actually met the lead mechanic for Bissel at Solvang. He's from Cadillac Michigan BTW. He seemed interested in getting a test on the Vred tubulars that they were using. I emailed him as well as Eric Wohlburg and actually talked directly to Eric at the start of the local Mt. Hamilton road race this summer but they weren't interested in testing the tire. We joked that they were committed to the tire sponsor and just didn't want to know. I mentioned that if his riders were ever in a situation where they needed every second or watt available that other tires would probably be better - rebadge or just black out the label - tough to find anything fast in RED however. To his credit he was very loyal to his tire sponsor. The other thing here is that Zirbel was really racing for USA Cycling - not sure how the teams enter into this but it would seem that the riders might be free to use whatever equipment they might choose although having said that they most likely would prefer their current racing gear. Too bad that he couldn't have scored a set of Garmin TT wheels and tires - JV is all over this stuff.

Re: 2009 Men's World Time Trial - Tire Choice 8 years, 2 months ago #25420

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Wait.... the close-up is from Colorado Cyclist of an actual Vredstein, for comparison with the photo of Tom's bike. The red stripes seem to match, anyway.

BTW, a few months ago I asked Eric Wohlberg how he liked his Pinarello. "It's the best bike I've ever ridden," was his response. I'm personally not a fan of Pinarello (I've never ridden one, though, but too many curves and too much paint is my feeling...) so that wasn't the answer I was after.

Re: 2009 Men's World Time Trial - Tire Choice 8 years, 2 months ago #25421

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djconnel wrote:
Wait.... the close-up is from Colorado Cyclist of an actual Vredstein, for comparison with the photo of Tom's bike. The red stripes seem to match, anyway.


Oh, right - I knew that . I thought maybe you did a CSI on the Zirbel tire - you know where they obtain huge amounts of detail from a single pixel. The stripes do match - I'm no expert but I don't think there are other tubulars out there of that color ??

Here is a link from the Bissel website showing wheels and tires:

http://www.bissellprocycling.com/Sponso ... stein.html

And a photo of Zirbel on his second place ride in the Elite Natz Time Trial - looks like the same bike and wheels which would make sense. The rear disc looks like a deep rim wheel with a cover ??

http://www.bissellprocycling.com/Photos ... -29/01.jpg

edit - forgot to add the second link

Re: 2009 Men's World Time Trial - Tire Choice 8 years, 2 months ago #25422

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He said he was on Vredesteins.
I ran Chrono CS 20 front and rear - No If only for me...
If only I was on vredesteins I wouldnt have cornered like a scared rabbit!
There was possibly an equivalent time to make up using well cornering tyres as opposed to well rolling.
dmc

Re: 2009 Men's World Time Trial - Tire Choice 8 years, 2 months ago #25423

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DMC wrote:
He said he was on Vredesteins.
I ran Chrono CS 20 front and rear - No If only for me...
If only I was on vredesteins I wouldnt have cornered like a scared rabbit!
There was possibly an equivalent time to make up using well cornering tyres as opposed to well rolling.
dmc


Thanks and again congratulations on the great ride. Just curious - do the narrow Cronos slide out or are you very cautious on them. At Solvang Garmin was using the Vittoria CX 23 on their front Zipp 1080 wheels but stuck with the Crono on the rear disc. JV said for aero dynamics - talked to him after the TT. When I saw there bikes before the race with that tire mix I thought that the mechanics had gotten the instructions backwards ?? If the course is technical it might make sense to go for a wider but easy rolling tire such as the RXL Pro although you might incur some aero losses ??

Just curious again but does the subject of slow rolling Continentals ever come up with the Columbia guys ?? Also any knowlege of what tires Cancellara was using - I'm guessing the Specialized (Vittoria) Mondo tubulars ?? Sorry for all the questions - please ignore if I'm out of line.

Re: 2009 Men's World Time Trial - Tire Choice 8 years, 2 months ago #25424

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FWIW, when considering the Solvang course two years ago (and courses with a significant amount of corners in general), the TT athletes I was working with gave narrow tires the thumbs down, particularly on the front, due to handling concerns as well as gluing concerns on the wider rims we were using. The mechanics were also concerned about gluing issues. So, we put CX 23's on on the front. During the season we used 21's on some of the rear disks since the rims were a touch narrower and we had those tires available and we wanted to use them up. All of our other wheels that year had the same wider rims as our TT specific wheels...and the guys weren't comfy with the narrow tires on those rims period.


In terms of equipment flexibility at World Championship events, this is very team and sponsor specific, IME. Most of the time, again IME, is it required by contract that riders use trade team sponsor correct equipment if selected for such events unless the team cannot or chooses not to provide such equipment. I've had to actually deal with sponsorship issues when a team rider used a correctly painted frame (done by the rider independent of team management knowledge) at the World Championships...but the frame was not a frame provided to the rider by the team/sponsor. So, it can be quite strict.

PS...the same guys rode mostly 21's the year before on narrower rims. I think they just likely the bigger tires, especially in light of how things looked when putting a 21 on the new wider rims.

Re: 2009 Men's World Time Trial - Tire Choice 8 years, 2 months ago #25425

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Kirk wrote:
FWIW, when considering the Solvang course two years ago (and courses with a significant amount of corners in general), the TT athletes I was working with gave narrow tires the thumbs down, particularly on the front, due to handling concerns as well as gluing concerns on the wider rims we were using. The mechanics were also concerned about gluing issues. So, we put CX 23's on on the front. During the season we used 21's on some of the rear disks since the rims were a touch narrower and we had those tires available and we wanted to use them up. All of our other wheels that year had the same wider rims as our TT specific wheels...and the guys weren't comfy with the narrow tires on those rims period.


In terms of equipment flexibility at World Championship events, this is very team and sponsor specific, IME. Most of the time, again IME, is it required by contract that riders use trade team sponsor correct equipment if selected for such events unless the team cannot or chooses not to provide such equipment. I've had to actually deal with sponsorship issues when a team rider used a correctly painted frame (done by the rider independent of team management knowledge) at the World Championships...but the frame was not a frame provided to the rider by the team/sponsor. So, it can be quite strict.

PS...the same guys rode mostly 21's the year before on narrower rims. I think they just likely the bigger tires, especially in light of how things looked when putting a 21 on the new wider rims.


Thanks Kirk - makes sense. The move toward wider rims carries the wider tires with it which probably handle better and are possibly more reliable but also roll well. I'd guess there might be some aero penalty at low yaw angles with the wider rims ?? I have a VF Record tubular on a front 1080 and it does look lost in the wide tire bed. Also dry fit a Record into a C2 Stinger 9 rim which was even worse.

My experience (which is very much less than yours and really only covers one person) was a rider on a team sponsored by Schwalbe. She used Vittoria Crono tires for TT's but blacked out the sidewall label. I suppose that there was some type of understanding with Schwalbe on this ?? There were rules on equipment logos as well - she pulled all the labels off the Zipp wheels.

A complex situation. Would Vred be better off if TZ had used faster tires and made the podium with the attendant spike in publicity ?? Maybe they would sell more tires as the general public wouldn't realize ?? Next year he will be with Garmin and on faster tires (??) so possibly his day will come. But I can't help but think that his day could have easily come this year.

Re: 2009 Men's World Time Trial - Tire Choice 8 years, 2 months ago #25429

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From the pictures I definately agree, Zirbel does seem to be on Vredsteins. Anyway he did put in a very strong effort and it's exciting to see him for Garmin-Slipstream in 2010. Another thought, he may actually be able to get that championship from DZ, when they compeat at the same equipment.

Just funny that these guys will actually accept such disadvantage to use sponsored equipment. I mean tires are not exactly the most expensive equipment. On the other hand it also goes to show that a majority of riders still don't pay to much attention to rolling resistance. I still often hear people talking about how well their narrow tires roll and that 23 mm tires are slow and not aerodynamic. If they only knew..... it would be hard to beat them in sprints and intervals on our group rides D

Re: 2009 Men's World Time Trial - Tire Choice 8 years, 2 months ago #25434

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tcramer wrote:

Just funny that these guys will actually accept such disadvantage to use sponsored equipment.


Another way to consider this topic is that it's funny that folks who believe that a disadvantage exists are unable to really satisfactorily "prove" that a disadvantage actually exists.

Something to consider, anyways!

-k
-kraig

Re: 2009 Men's World Time Trial - Tire Choice 8 years, 2 months ago #25438

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AFM wrote:


Thanks and again congratulations on the great ride. Just curious - do the narrow Cronos slide out or are you very cautious on them. At Solvang Garmin was using the Vittoria CX 23 on their front Zipp 1080 wheels but stuck with the Crono on the rear disc. JV said for aero dynamics - talked to him after the TT. When I saw there bikes before the race with that tire mix I thought that the mechanics had gotten the instructions backwards ?? If the course is technical it might make sense to go for a wider but easy rolling tire such as the RXL Pro although you might incur some aero losses ??

Just curious again but does the subject of slow rolling Continentals ever come up with the Columbia guys ?? Also any knowlege of what tires Cancellara was using - I'm guessing the Specialized (Vittoria) Mondo tubulars ?? Sorry for all the questions - please ignore if I'm out of line.


Never had any slipping with the CS's, Just me being overly cautious. I think if they are not overinflated they should grip pretty well.
I bought a new 1080 and forgot that with the wider rim it is maybe just as aero to run a wider tyre anyway.

I am surprised to hear the vredesteins fare so badly in rolling tests. Havnt used them in a few years, but I remember them looking very similar to Vittoria cxs.
Not so?



One possible other problem that I might have been subconciously sensing and making me go easy was the Zhitt 1080 wheels hitting the brake blocks if you lean over enough ( ie. not very much at all). Not nice to have the brakes rubbing when trying to corner at speed. i had my brakes as loose as I could and still be effective, and still they slapped the brakes any time I rode out of the saddle. Did this every time up the hill and I decided to just put up with it.
Every zipp I have had has done this ,404, 808 now 1080. Just bought a new 1080 and thought it would be better than before, but still the sloppiest brand of wheels I have ridden. Curious if some of the 'big' names have specially tuned ones. I might try tightening the spoke up to see if that helps. But i wonder if it is more the hhub at fault than the spoke tension. any ideas?

If that fails - I will not be riding zipps again anywhere with corners or steep uphills.

DMC

specialized tubs 8 years, 2 months ago #25439

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anyone recognise what this might be.
Had thought they might be dugasts, but apparently not.

That said - The wheels reviewed might not be what he uses.

http://autobus.cyclingnews.com/photos/2 ... 28---tyres

http://autobus.cyclingnews.com/photos/2 ... ansition09

Re: 2009 Men's World Time Trial - Tire Choice 8 years, 2 months ago #25440

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http://www.canadiancyclist.com/races09/ ... /index.htm

Looks like Larsson s on skinner tyres to cancellera too.

Re: 2009 Men's World Time Trial - Tire Choice 8 years, 2 months ago #25441

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kraig wrote:
tcramer wrote:

Just funny that these guys will actually accept such disadvantage to use sponsored equipment.


Another way to consider this topic is that it's funny that folks who believe that a disadvantage exists are unable to really satisfactorily "prove" that a disadvantage actually exists.

Something to consider, anyways!

-k


Very true - I'm taking very limited (in most cases "one off" tests) on smooth rollers and applying the results to real roads. I'm convinced that in my specific case comparing race results on "identical set ups" but with different tires - Tufo Jet Special S3 vs. original Zipp tubulars - that the trend of the smooth roller data matched the real world. I guess it's my background as a development engineer where one big constraint is time to market. We had to make decisions based on soft data and hope that it all worked out for the best or at least did not negatively affect the final product. It's much easier to act on big differences but small ones remain questionable with limited data and consequent lack of statistical analysis. Hopefully though the "small differences" are indeed small. ) )

Re: specialized tubs 8 years, 2 months ago #25442

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DMC wrote:
anyone recognise what this might be.
Had thought they might be dugasts, but apparently not.

That said - The wheels reviewed might not be what he uses.

http://autobus.cyclingnews.com/photos/2 ... 28---tyres

http://autobus.cyclingnews.com/photos/2 ... ansition09


I haven't tested the Specialized tubulars but one of our members has. I believe they are made for Specialized by Vittoria as the Specialized clinchers are. The new Specialized Mondo Open tubulars was very fast - another of the "one off" conclusions again.

http://www.specialized.com/us/en/bc/SBC ... 4&eid=5098

Re: 2009 Men's World Time Trial - Tire Choice 8 years, 2 months ago #25443

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DMC wrote:


Never had any slipping with the CS's, Just me being overly cautious. I think if they are not overinflated they should grip pretty well.
I bought a new 1080 and forgot that with the wider rim it is maybe just as aero to run a wider tyre anyway.

I am surprised to hear the vredesteins fare so badly in rolling tests. Havnt used them in a few years, but I remember them looking very similar to Vittoria cxs.
Not so?



One possible other problem that I might have been subconciously sensing and making me go easy was the Zhitt 1080 wheels hitting the brake blocks if you lean over enough ( ie. not very much at all). Not nice to have the brakes rubbing when trying to corner at speed. i had my brakes as loose as I could and still be effective, and still they slapped the brakes any time I rode out of the saddle. Did this every time up the hill and I decided to just put up with it.
Every zipp I have had has done this ,404, 808 now 1080. Just bought a new 1080 and thought it would be better than before, but still the sloppiest brand of wheels I have ridden. Curious if some of the 'big' names have specially tuned ones. I might try tightening the spoke up to see if that helps. But i wonder if it is more the hhub at fault than the spoke tension. any ideas?

If that fails - I will not be riding zipps again anywhere with corners or steep uphills.

DMC


Thanks for sharing - always interesting to get perspectives from someone right at the top of the sport.

The problem with the 1080 might be just the low number of spokes and the short length. I know that Zipp won't supply and strongly advises not to use the 1080 rim with a PT hub which would have slightly shorter spokes. Ron who builds wheels and is very good at it from all accounts would know far more than I. I put a VF Record tubular on my front 1080 and filled in the gap with liquid latex. It does look a bit funny with that skinny little tire hiding in the wide tire bed.

Again the Vred tubular that I tested 2 years ago was on a friends race wheel so I really don't know how old it was, how many miles on it, how it was glued, etc... I do know that the Vred Tri Comp clincher that I tested didn't roll very well. Too bad that I couldn't get one of the Bissel used tubulars but Bissel is very loyal to their sponsor and consequently wasn't interested in sending me a tire to test.

Al

Re: 2009 Men's World Time Trial - Tire Choice 8 years, 2 months ago #25444

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Shorter spokes would make the wheel stiffer, and a deeper rim improves the bracing angle for lateral loading as far as the spokes are concerned. The problem is likely occurring between the spoke bed and the rim... ie flex within the rim sidewalls. If it is a Zipp hub it might also be due to low tension on the NDS. They only allow 100kg on the DS which leaves only 40kg (or a bit less) on the NDS with the older hub design. The new hubs have a better flange spacing but they also radial lace the DS... so the lightly tensioned NDS must take all the torque loads. If any of the spokes go slack the stiffness drops a lot.

I haven't built a 1080, but a sponsored rider sent me a new 1080 rear wheel to check for tension and balance awhile back. The NDS tension was all over the place... so that might be a good thing to check.

BTW... The PT prohibition is likely due to the nipples having extreme angles inside the rim. You could lace a 20h rim 1x on both sides though, and everything would be fine. I also bend the spokes slightly just above the nipples so that the nipples are more in-line with the rim.

Re: 2009 Men's World Time Trial - Tire Choice 8 years, 2 months ago #25446

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kraig wrote:
tcramer wrote:

Just funny that these guys will actually accept such disadvantage to use sponsored equipment.


Another way to consider this topic is that it's funny that folks who believe that a disadvantage exists are unable to really satisfactorily "prove" that a disadvantage actually exists.

Something to consider, anyways!

-k




whoa, that probably didn't come across like I had intended...no offense intended, there, BTW - sorry about that!

I, for one, believe that some tires can be a disadvantage. I'm not sure about the magnitudes at play, however. It's tricky business, I reckon.
-kraig

Re: 2009 Men's World Time Trial - Tire Choice 8 years, 2 months ago #25448

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No offense taken. I partly agree thinking that most of the crr testing done is not tested under strictly scientific criterias and therefore does have some potential faults. Not a critic, thats just the way it can be done without the cost of a space ship and still does provide a lot of interesting info. Also I am still thinking that maybe the pro's get special versions, like tires that have a less thick thread etc. Or maybe the mecanics simply take sanded paper and make the thread thinner by hand or maybe they have other tricks. I don't know, lot's of possibilities and really there is no way to prove which one of these guys were on the fastest equipment. But untill someone shows something different and provable better I take AFM's testing over any of the other tests out there!

Re: 2009 Men's World Time Trial - Tire Choice 8 years, 2 months ago #25454

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By the way I spent some time checking the tension on my zipp 303, 404 and 808 (front) wheels, and build a 404 rearwheel a while ago. I used the Tacx spoke tension meter and wow there were a lot to gain. All of my zipp wheels had lower tension than the specified tension from zipp. I can only say after the tension was dialed in and the wheels were perfectly true they felt like a completely different wheel a lot stiffer and way better in corners.

I know that many shops in Denmark and probably the rest of Europe are building the zipp wheels them selves as it saves them a lot of shipping costs. But not many shops atleast here in Denmark use a tension meter. They do it by feel, which can be ok if they have enough experience but not everyone has.

Hitting the scale at around 74-75 kg these days (used to be more like 71 kg) I have never experienced any rubbing from my zipp wheels except from the disc wheel one time where I forgot to center the brake and it was very close to the rim.

Re: 2009 Men's World Time Trial - Tire Choice 8 years, 2 months ago #25455

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r.e. the flexy Zipps, I know that Damon Rinard did some test a long time ago which is still floating around the intertubes which seems to indicate that as long as the spokes aren't slack, tension really doesn't contribute to tension. IIRC, is was mostly a matter of spoke count and gauge. I don't recall how much bracing angle factored in.

I know that with my 808's, the FRONT would actually rub during a sprint, and I tend to run my brakes really wide open.

r.e. Kraig's comment about figuring out rolling losses in the real world, I'm of like mind: I think it's pretty complicated, particularly when you're trying to sort out small differences.

r.e. those Specialized tubulars, they're fast rolling on rollers--slightly faster than the Bontragers. I should mention though that a friend of mine is blaming them for 3 wet-weather slide-outs. I've used the Bonty's in the rain with good success, I figured the Specialized would be the same, or better, since they're wider. I have limited wet-weather experience with them, but I haven't noticed a problem. The guy who's crashed on them is a pretty good bike handler so I'll admit it concerns me a little. Take that FWIW.

Re: 2009 Men's World Time Trial - Tire Choice 8 years, 2 months ago #25456

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Brake pad rub:

I measured on-road, between the pad, dynamic deflection for several wheels in this review:

http://www.biketechreview.com/archive/wheel_review.htm

one takeaway from that exercise for me, was that i couldn't necessarily perceive the pad rub, but when the physical measurements were made, it was a bit surprising to see the magnitudes.

also, back in my brand-s days, we had a fixture that rigidly supported the axle and allowed for assesment of between the pad deflection and simultaneous deflection at the road contact point. from memory, some of the lowest stiffness (at the road contact point) also had the lowest deflection between the pads.

the deep section/high section inertia, low spoke count wheels had some of the highest deflections between the pads. the low-tech explanation I came up with at the time is simply that the rim and spoke "stiffness" are not matched, and as a result, the stiff rims just "tilt" when a lateral load is applied.

The low section inertia rims (i.e GL280/ambrosio chrono) just bend under lateral loads, taking on the "potato chip" deformed shape, and there is very little between the pad deflection.

I can remember when I was trying to correlate a simple FEA model (shell rim elements/beam elements for spokes) I worked through a progression of spoke counts...going from 4 spokes up to std levels...I even rode some of those really low spoke count wheels in the parking lot and remember those suckers bangin off the pads. Hey, here's another wheel with unmatched rim/spoke stiffness that suffered from serious pad rubbage:

http://www.biketechreview.com/misc/hangin_hub.htm

Yeah, boundary condition stuff can affect between the pad deflection as well -> I reckon a more flexible boundary condition would amplify "rim tilt".

But, all that stuff happened a long time ago, so, I've probably got some things mis-remembered...anybody else look at this kind of stuff either in FEA land or "real-life" land?
-kraig

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