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Princeton CarbonWorks "white paper"
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So I read the front page article and I wanted to see some sort of explanation of why the wavy inner edge of the wheel is supposed to be better. It's not obvious to me why it would be. So I was happy to find a link to their white paper on their website:

https://www.princetoncarbon.com/...-Speed-Wake-6560.pdf

It's more than a little disappointing. There is literally no information whatsoever. Just lots of, we are ivy-league super nerds that used aerospace engineering and finite element analysis. Look at this chart we made that shows our wheel to be fastest. (the "white paper" provides no information at all about how the chart was made. Not even if it was wind tunnel testing, or anything)

As an engineer who is developing an aerodynamic cycling product under a completely new brand, I plan on backing it up with as much info as possible. In fact, 9 months or so before even being able to release a product, I think I have already provided infinitely more information than these guys have....

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Ed O'Malley
www.VeloVetta.com
VeloVetta is developing AERO cycling shoes with CFD and wind tunnel testing.
Instagram • Facebook
Last edited by: RowToTri: Sep 2, 18 15:05
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Re: Princeton CarbonWorks "white paper" [RowToTri] [ In reply to ]
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Agreed. I am somewhat interested in these wheels, but the “white paper”—if you can even credibly call it that—is rather sparse.

Edit: there is more info from testing in the website.
Last edited by: DFW_Tri: Sep 3, 18 13:21
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Re: Princeton CarbonWorks "white paper" [RowToTri] [ In reply to ]
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Ed, from what I see the post you link to is pretty straight forward:


"It’s just a memo – about how Princeton CarbonWorks makes you faster." Maybe the error was simply how the document was named.


There is now a button on the landing page, and a minimal amount of digging gets you to the following two links (below) - the data is coming straight out of the tunnel at A2. We paid for competitors product to test against it, and are transparent about it.

https://www.princetoncarbon.com/news/the-numbers/


https://www.princetoncarbon.com/...wind-tunnel-visit-2/

Paul Daniels
paul@princetoncarbon.com
http://www.princetoncarbon.com
Last edited by: Paul at PCW: Sep 16, 18 11:11
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Re: Princeton CarbonWorks "white paper" [elevelo] [ In reply to ]
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Ok, so there is a yaw chart and they say that they used the same tire on all wheels and they were tested at 30mph. That's better than the white paper - why in the heck would they produce a white paper that excludes any of this information??

The fact that they used the same tire on all wheels essentially invalidates the test and the fact that at 30mph the max difference from fastest wheel to slowest is 9 g through 74% of the time-weighted yaw distribution gives me confidence that I cannot really make a huge mistake in wheel selection. I'd also prefer a test on a bike with a rider, not a wheel by itself.

They are not the only wheel manufacturer to make under-substantiated claims and they are not the worst. Enve is certainly worse.

For a good white paper, I refer you to the Roval CLX50 in combination with the questions they answered here on Slowtwitch to address the shortcomings in the paper.

I am not making wheels, I'm making shoes. I will release detailed aero testing and detailed information about the protocol. I have already released CFD simulation results on an early design.

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Ed O'Malley
www.VeloVetta.com
VeloVetta is developing AERO cycling shoes with CFD and wind tunnel testing.
Instagram • Facebook
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Re: Princeton CarbonWorks "white paper" [RowToTri] [ In reply to ]
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This is not a "white paper". This is a 1st year, freshman paper. No references. No science. No foundation and nothing built upon.
This is not for industry insiders. This is not even marketing. It's, literally, a D- freshman paper from early in the semester. There is a lot of room to grow here, but a lack of scientific references and the massive amounts of bullshit are hilarious.

I'm an adjunct (SLAVE) to many horrible state level College/University institutions. I give this a rock solid D-
When student pulls head out of his ass....he'll get a C or B- at best.
Last edited by: 2YearstoIronman: Sep 5, 18 16:11
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Re: Princeton CarbonWorks "white paper" [elevelo] [ In reply to ]
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yeah, no claim to be a whitepaper just some marketing material. they have however included more detail and actual comparative test result numbers than many larger manufacturers do so should be given some credit for that. if we want manufacturers to provide information we have to be somewhat forgiving if they don't do it exactly as we might want - provide constructive feedback and ask questions to help the industry lift its game rather than discouraging them from even trying.

testing with a 23mm GP4K is pretty standard - it might not be the "best" protocol but i believe it is what zipp themselves test with so when comparing themselves to zipp this doesn't seem to be biased at all.

yes, there is a lot of protocol detail missing but the vast majority of consumers won't understand most of that. the only thing that makes this information suspicious to me is just how well their ~60mm wheel compares to zipp's ~80mm on speed, while being lighter than zipp's ~60mm. there may well be some issues with the protocol that would counter that but i wouldn't expect so much so as to not leave these as very light and fast wheels for their depth.

how well they ride and last who knows...
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Re: Princeton CarbonWorks "white paper" [pk1] [ In reply to ]
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Post 1 of hopefully many (got my Slowtwitch login!)

Being super candid here, would love feedback as we are a young company entering a very highly discerning market:

We designed the WAKE6560 to really upend what everyone thought was possible from a medium to deep aero wheel. A lot of work went in to optimizing shape, and while the trend is leaning towards wider and wider, the reality of it is that we spend 90+% of our time between 0-10 degrees yaw... Like Dan mentioned in his write up, the majority of the aero benefits of a deep wheel occur at high yaw angles (that "pushing" sensation of negative drag) because, after all, the rim is acting like a wing; however, that cross section will definitely pull you around the road, and all those wobbles will kill any aero benefit you achieve.

A few people are discussing our relatively narrow width compared to current competitors. This was a design choice that will allow much better performance in the 0-10 degree zone we all spend the majority of our time in. Paired with an undulating/continuously varying trailing edge on the front section of the wheel gives us much better cross wind performance as well as myriad structural benefits.

Our width and depth are optimized for a variety of yaw scenarios, so you get exceptional low yaw performance (due to moderate width), and still achieve negative drag at higher yaw angles (due to 60+mm depth), all with more stability (due to continuously varying trailing edge).

Notice, the 6560 uses a symmetrical sinusoidal wave, whereas a 454 uses a sawtooth (asymmetrical, read stress concentrator)...Our sine waves allow much greater stress migration from the spoke point to the outer hoop (the strongest part of the rim) so we can use less material in certain areas while still achieving greater stiffness. The concept of putting the spoke at the convex point of the sine allows us to use unidirectional fibers in tension (whereas all other rims have the spoke point on a concavity, putting the carbon into compression.) Fibers work really well in tension, not as great in compression, so simple stuff that gives us huge benefits.

The result is a wheel that is aerodynamically faster than 404, 454, 858, jet6, jet9, etc etc, but also lighter (considerably) and stiffer (we are working on ways to quantitatively measure deflection without destroying expensive competitor wheels we need to buy for testing!) with better cross wind performance.

As for protocol, we followed a very strict testing protocol and all tests were performed by staff at A2. To be honest, the days are fairly long and boring, as we are just swapping tires, checking pressures, loading into the test rig and waiting about 10 minutes for the test to run. We did test our wheels on a bike with a rider against a few other (404 namely) and have those numbers somewhere, I will dig them up (we were considerably lower drag).

This is our first product of many; we aren't trying to hawk wheels like a lot of sticker brands are, we are trying to engineer a better solution for the rider to ultimately go faster, more comfortably, and more reliably. The goal is better speed under all conditions.
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Re: Princeton CarbonWorks "white paper" [hajamac] [ In reply to ]
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hajamac wrote:
the reality of it is that we spend 90+% of our time between 0-10 degrees yaw

welcome. now that you're here, you oughta go over and weigh in on the hambini thread. especially on the question of time @ yaw ;-)

hajamac wrote:
Paired with an undulating/continuously varying trailing edge on the front section of the wheel gives us much better cross wind performance as well as myriad structural benefits... all with more stability (due to continuously varying trailing edge).

what i'd like is a more thorough discussion of how this works. how separation is maintained, rather than separation, reconnection, separation, reconnection. or, how i probably inexpertly put it, a recurring stall of the wheel. as hambini (i think it was he) pointed out, the problem isn't steering torque, it's the change in steering torque as the wheel repeatedly capitulates and reengages.

Dan Empfield
aka Slowman
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Re: Princeton CarbonWorks "white paper" [Slowman] [ In reply to ]
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A simple way to visualize is this:

In college we had these tall class buildings with very straight sides and narrow alleyway between them. Dead center down the length of the alley way was toll-booth type rail (technically called a boom barrier, thanks wikipedia: https://en.wikipedia.org/wiki/Boom_barrier).

The boom barrier was kept in the down position to prevent students from diving down the alleyway, and only opened for staff and faculty. During windy Boston winters and springs, the the buildings literally created a massive wind tunnel, funneling wind into the alleyway.

When describing vortex shedding and pressure flop, a professor pointed out the boom barrier in the alleyway. "Notice how as the windspeed increases, the boom barrier (which was a perfect cylinder rod) starts to vibrate and harmonize" ie, shake up and down. The simple explanation for this is that as vortices form towards the trailing edge of the body, they never do so in perfect symmetry. There will be slight variations in pressure from one side to the other, which flip-flop back and forth. This pressure flip-flop is what caused the boom barrier to vibrate and harmonize as the windspeed increased down the alley way.

This is a good visualization of the pressure flop trailing the body: https://www.youtube.com/watch?v=IPBKR9cSce0

Now, by varying the trailing edge, we kind of trick the pressure flop (or at least greatly mitigate it) because it can never form to a large extent. This reduces instability that will occur as a result of the vortices shedding off a uniform body.

This was a pretty basic explanation, I can go back and get some maths out to explain in more depth if required!

Can you link to hambini? H
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Re: Princeton CarbonWorks "white paper" [Slowman] [ In reply to ]
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I believe the uneven undulations set up the departing airflow for a slight spin, and spinning mass while moving is more stable than a stationary one. This makes the departing air more stable and smoother, less likely to be fluttery and stalling.

Fluids seek stability when moving at speed by spinning. That's why tornados form when air masses collide and water spins down a drain instead of just falling in. You an pre-initiate that spin by putting bumps on the wheel, like putting rifling in a gun barrel to initiate the spin of a bullet.

My big question is what are the chances the perfect rifling pattern to spin air off a wheel moving at 20 mph also happens to be the same frequency as a spoke count on a wheel? Are we sure that every other spoke wouldn't work better? Or twice per spoke gap?

----------------------------------------------------------
Zen and the Art of Triathlon. Strava Workout Log
Interviews with Chris McCormack, Helle Frederikson, Angela Naeth, and many more.
http://www.zentriathlon.com
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Re: Princeton CarbonWorks "white paper" [2YearstoIronman] [ In reply to ]
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2YearstoIronman wrote:
This is not a "white paper". This is a 1st year, freshman paper. No references. No science. No foundation and nothing built upon.
This is not for industry insiders. This is not even marketing. It's, literally, a D- freshman paper from early in the semester. There is a lot of room to grow here, but a lack of scientific references and the massive amounts of bullshit are hilarious.

I'm an adjunct (SLAVE) to many horrible state level College/University institutions. I give this a rock solid D-
When student pulls head out of his ass....he'll get a C or B- at best.

Oh, so it's a wipe paper...
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Re: Princeton CarbonWorks "white paper" [FatandSlow] [ In reply to ]
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I think you mean Dwight-paper

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Re: Princeton CarbonWorks "white paper" [RowToTri] [ In reply to ]
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RowToTri wrote:
The fact that they used the same tire on all wheels essentially invalidates the test and the fact that at 30mph the max difference from fastest wheel to slowest is 9 g through 74% of the time-weighted yaw distribution gives me confidence that I cannot really make a huge mistake in wheel selection.

Yes. But remember, differences in the tire / tire pressure alone can account for "hundreds of grams" of drag. Right?
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Re: Princeton CarbonWorks "white paper" [hajamac] [ In reply to ]
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hajamac wrote:
As for protocol, we followed a very strict testing protocol and all tests were performed by staff at A2. To be honest, the days are fairly long and boring, as we are just swapping tires, checking pressures, loading into the test rig and waiting about 10 minutes for the test to run.

I don't understand why these comparative wheel studies aren't done with the tires and pressures recommended by the competitors to be fastest for their specific wheel -- that is the proper protocol. Normalizing the same width tire at the same pressure just doesn't seem to make sense here. So before the test, you find the right contact at Zipp or Enve, and pick up that tire and test at that pressure recommended by that person. If they don't recommend anything, you note that in the results and run your 23 mm GP2 or whatever. What am I missing here? 90 PSI for a wheel with 17mm inner diameter is significantly different than for a wheel with a 21.5 inner diameter. That's before you even get to the tires. Is Zipp going to recommend their own tires? Let's test that.
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Re: Princeton CarbonWorks "white paper" [hajamac] [ In reply to ]
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hajamac wrote:
Our width and depth are optimized for a variety of yaw scenarios, so you get exceptional low yaw performance (due to moderate width), and still achieve negative drag at higher yaw angles (due to 60+mm depth), all with more stability (due to continuously varying trailing edge).

But yet you will be running higher pressures, which means less comfort, and probably higher rolling resistance. The fastest wheel isn't the fastest wheel aerodynamically, just like the fastest tire isn't the fastest tire aerodynamically. It's the entire system together (tire, wheel, pressure) with the combined net of rolling resistance and aerodynamics. I'm not the engineer, but that much is pretty intuitive to me.

Again, comparative study protocols on wheels should marry Tom A. type tire studies with the recommended tires and pressures recommended by the manufacturer of the wheel tested. You guys are smart guys -- I'm sure you could figure out how to calculate with a fair degree of precision how to weight each of the data to come up with a "resistance" measure that is a combination of these things. So why hasn't anyone done it? It's like I have to guess.

I suppose there is a final variable which is "durability of the tire", which would be much much tougher to quantify. The Vittoria Corsa Speed or whatever the new one is called may be the fastest tire both in rolling resistance and aero (depending entirely on which wheel it's on and at what pressure it is tested) but yet you have a 25% chance of flatting over 112 miles...at least in my experience. I wouldn't choose to run that tire outside the velodrome.
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Re: Princeton CarbonWorks "white paper" [kileyay] [ In reply to ]
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WAKE 6560 is tubeless ready. This choice was made in consideration for tire pressure/rolling resistance while optimizing aerodynamics which dictated the modest 18mm internal width. Meanwhile the 454 internal width is 17mm and not tubeless. The fastest wheel over a set course may not be fastest wheel in the tunnel, that's entirely possible. We understand that - and believe the fastest wheel system for a course has top level aerodynamics with attributes that allow optimization of rolling resistance while inhibiting puncture mechanicals. Tubeless in our view is a bridge to better speed. Because end of the day a mechanical on the fastest wheels yields a slower bike leg than a 32 spoked box-section without mechanical.


"Again, comparative study protocols on wheels should marry Tom A. type tire studies with the recommended tires and pressures recommended by the manufacturer of the wheel tested. You guys are smart guys -- I'm sure you could figure out how to calculate with a fair degree of precision how to weight each of the data to come up with a "resistance" measure that is a combination of these things. So why hasn't anyone done it? It's like I have to guess."


This is a great suggestion ^^^





Paul Daniels
paul@princetoncarbon.com
http://www.princetoncarbon.com
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Re: Princeton CarbonWorks "white paper" [RowToTri] [ In reply to ]
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interesting thread and good discussion on a new product. im very interested in these as i rented a set of 858s for my first 70.3 and i could tell a difference in their cross wind handling versus my deeper "standard" wheelset.

2019 Schedule: Ironman 70.3 Texas April 7...
Last edited by: damon.lebeouf: Sep 8, 18 12:53
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Re: Princeton CarbonWorks "white paper" [damon.lebeouf] [ In reply to ]
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We have a very active demo program going on right now for those looking to whip a set for a week or two;

If you check out the contact page at http://www.princetoncarbon.com or email info@princetoncarbon.com Paul will gladly talk you through our demo program!

We have a LOT of exciting progress in the works, including some pretty groundbreaking tech in regards to construction/manufacturing, it has been a wild ride so far-

H
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Re: Princeton CarbonWorks "white paper" [hajamac] [ In reply to ]
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hajamac wrote:
We have a very active demo program going on right now for those looking to whip a set for a week or two;

If you check out the contact page at http://www.princetoncarbon.com or email info@princetoncarbon.com Paul will gladly talk you through our demo program!

We have a LOT of exciting progress in the works, including some pretty groundbreaking tech in regards to construction/manufacturing, it has been a wild ride so far-

H

im def going to take advantage of this. already contacted you guys. thanks for this program!

2019 Schedule: Ironman 70.3 Texas April 7...
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Re: Princeton CarbonWorks "white paper" [hajamac] [ In reply to ]
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hajamac wrote:

The result is a wheel that is aerodynamically faster than 404, 454, 858, jet6, jet9, etc etc,

That's a bold statement...

Quote:
We did test our wheels on a bike with a rider against a few other (404 namely) and have those numbers somewhere, I will dig them up (we were considerably lower drag).

...but wait, you tested against the 404? How do you know it's aerodynamically faster than an 858 or Jet 9+? Wheel-only testing? What other testing conditions?
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Re: Princeton CarbonWorks "white paper" [trail] [ In reply to ]
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1) Not bold, true. Can provide drag readings at yaw (measured every 2.5 degrees). Also part of the reason why we think these wheels are a big deal.

2) We had some extra time on our first trip to the windtunnel (when we were testing our V0 "prototype" wheels in March of 2017) and were able to do back to back testing of a full bike, rider, and wheelset, but only for our V0 wheels and the 404s. The 404, 454, 858, Jet6 Jet9 testing was done on our production wheels (V1 WAKE6560, tested December 2017) which were also tested that same day against our control (V0 prototype wheels from our first time at the tunnel). The second round of testing was wheels only and we do not have bike/rider/wheelset drag numbers from that day.

We operate in the interest of full transparency. If there is anything (literally ANYTHING) you want to know, just ask.
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Re: Princeton CarbonWorks "white paper" [hajamac] [ In reply to ]
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hajamac wrote:
1) Not bold, true. Can provide drag readings at yaw (measured every 2.5 degrees). Also part of the reason why we think these wheels are a big deal.

2) We had some extra time on our first trip to the windtunnel (when we were testing our V0 "prototype" wheels in March of 2017) and were able to do back to back testing of a full bike, rider, and wheelset, but only for our V0 wheels and the 404s. The 404, 454, 858, Jet6 Jet9 testing was done on our production wheels (V1 WAKE6560, tested December 2017) which were also tested that same day against our control (V0 prototype wheels from our first time at the tunnel). The second round of testing was wheels only and we do not have bike/rider/wheelset drag numbers from that day.

We operate in the interest of full transparency. If there is anything (literally ANYTHING) you want to know, just ask.
Drag vs. yaw graph(s) against those competing wheels would definitely be interesting to see :)
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Re: Princeton CarbonWorks "white paper" [MTM] [ In reply to ]
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MTM wrote:
hajamac wrote:
1) Not bold, true. Can provide drag readings at yaw (measured every 2.5 degrees). Also part of the reason why we think these wheels are a big deal.

2) We had some extra time on our first trip to the windtunnel (when we were testing our V0 "prototype" wheels in March of 2017) and were able to do back to back testing of a full bike, rider, and wheelset, but only for our V0 wheels and the 404s. The 404, 454, 858, Jet6 Jet9 testing was done on our production wheels (V1 WAKE6560, tested December 2017) which were also tested that same day against our control (V0 prototype wheels from our first time at the tunnel). The second round of testing was wheels only and we do not have bike/rider/wheelset drag numbers from that day.

We operate in the interest of full transparency. If there is anything (literally ANYTHING) you want to know, just ask.

Drag vs. yaw graph(s) against those competing wheels would definitely be interesting to see :)

go look on their website.

2019 Schedule: Ironman 70.3 Texas April 7...
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Re: Princeton CarbonWorks "white paper" [RowToTri] [ In reply to ]
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Sounds a lot like the Huub white papers. complete and utter rubbish.

'Here is a picture of me in my garden with some neoprene and a bucket of water ... see, faster'

Very disappointing when brands claim to back things up with white papers etc and some actual technical and scientific insight that the rest of us would find really interesting but in the end just give a word doc with some big words and no substance.
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Re: Princeton CarbonWorks "white paper" [jayski] [ In reply to ]
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jayski wrote:
Sounds a lot like the Huub white papers. complete and utter rubbish.

'Here is a picture of me in my garden with some neoprene and a bucket of water ... see, faster'

Very disappointing when brands claim to back things up with white papers etc and some actual technical and scientific insight that the rest of us would find really interesting but in the end just give a word doc with some big words and no substance.

its pretty obvious you didnt read the rest of the thread... just the first post.

2019 Schedule: Ironman 70.3 Texas April 7...
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