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Re: Triathlon Bikes in the Age of Peak Aero: here it is ;-) [Slowman] [ In reply to ]
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Slowman wrote:
i think i pretty clearly hear josh poertner saying that bike makers (and wheel makers) today ought to be accommodating a tire that measures 30mm in width. this ambivalence and uncertainty and impending shift in tech screams out for a disc brake solution.

Yeah -- I haven't read the later tired thread, but you can run a 28 on the rear of the Tactical. And the way the rear wheel is shrouded I bet you're not getting a huge aero penalty with a wide tire like that. As Dan says, the comfort trade off is probably worth it. I don't see why rim-brake based rims can't also be wider. The NSW is already pushing that way.

Slowman wrote:
but i acknowledge that before the andean hits its peak it's going to need another stem solution. that bike wants a new stem - that has the bosses on it above which its storage solution affixed - and that can accept another bar, like a zipp or a PD.

This is really my biggest issue with the Andean. Everything from the steerer forward (including the steerer) and especially the stem. I don't understand why they couldn't come up with a base bar like the one on the Tactical, which is just the most bad ass bar.

I think the jury is still out on whether the disc brake transition is on balance actually a good thing. Obviously we aren't going to have a choice soon. But in dry conditions with clean cable routing the TriRig/Premier brakes are in my opinion completely adequate, including on carbon clinchers.
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Re: Triathlon Bikes in the Age of Peak Aero: here it is ;-) [Slowman] [ In reply to ]
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I'm not ignoring your platform and halo bike talking points. I just think that narrative is moot. I'm not talking about what to buy in 3 years. I'm talking about what to buy right now. Based on real data we all now have.

It was much easier to price bicycles in the stratosphere when we all felt there were significant and measurable time savings to be had when forking over our hard earned dollars. Now we know only people who enjoy warming themselves over a fire of burning dollar bills would spend on a P5x.

Lets regroup in 3 years when we can then agree on this platform you speak of.

Also, Stan, my name is not robert. I'm upset you don't know this.

"One Line Robert"
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Re: Triathlon Bikes in the Age of Peak Aero: here it is ;-) [kileyay] [ In reply to ]
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So my 2014 Felt B16 I purchased on clearance brand new for 1400 bucks was a good deal I'm gathering? Now if I could only get the engine working better...

"There are two ways to slide easily through life- to believe everything and to doubt everything- both ways save us from thinking "- Korzbyski
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Re: Triathlon Bikes in the Age of Peak Aero: here it is ;-) [newguy] [ In reply to ]
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newguy wrote:
So my 2014 Felt B16 I purchased on clearance brand new for 1400 bucks was a good deal I'm gathering? Now if I could only get the engine working better...

No its not. Because it looks like this:


Which is a much different frame then the Felt tested.

I dont know how much easier this can be made beyond displaying photos right next to each other.

"One Line Robert"
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Re: Triathlon Bikes in the Age of Peak Aero: here it is ;-) [grumpier.mike] [ In reply to ]
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grumpier.mike wrote:
First. A big "Thanks" to everyone that helped with this project!

What I find really interesting is how much, or little, progress has been made over the last 7-8 years. To put this in perspective I went back and looked at the old Slowtwich article on the P4. http://[[url]http://www.slowtwitch.com/Tech/Cervelo_P4_in_the_Tunnel_1929.html/url]

Back in the day the P4, which is pretty close to the P5 at low yaw, was about 125-150 grams of drag lower than everything else. That's a pretty similar margin to what we see today.

So if you were pretty anal about setup (3T Ventus bar) and used a clean center-pull break (prior to TriRig) you might have seen no drag reduction since the P4 came out in 2009ish.

I still swear that the old P4 was/is faster than my P5-3.
Both in terms of the frame, the 'illegal' P4 bottle/fairing, and the lower headtube giving me a slightly lower, faster position.

All that said, the P5 is worlds better in everyday riding, and has brakes that actually work.

I know it loses some aero ground to the P5-6 and P5X, but not enough for me to ever consider having to "upgrade" it.


float , hammer , and jog

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Re: Triathlon Bikes in the Age of Peak Aero: here it is ;-) [wsrobert] [ In reply to ]
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Obviously for dummies like me pictures help 🙂

"There are two ways to slide easily through life- to believe everything and to doubt everything- both ways save us from thinking "- Korzbyski
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Re: Triathlon Bikes in the Age of Peak Aero: here it is ;-) [Slowman] [ In reply to ]
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the best bike and the worst were separated by where you choose to place your hydration.


I've said this for some time - glad to see it backed up. That for the most part there really is not much difference between the best bikes. The ill-placement of a water-bottle on the bike has more impact on the aerodynamics than the frames themselves.

So could we also conclude that with the rather significant variable of riders-aboard the bikes (that has a much greater impact on overall aerodynamics) that really the differences in the frames are insignificant in the real world.


Steve Fleck @stevefleck | Blog
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Re: Triathlon Bikes in the Age of Peak Aero: here it is ;-) [newguy] [ In reply to ]
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newguy wrote:
So my 2014 Felt B16 I purchased on clearance brand new for 1400 bucks was a good deal I'm gathering? Now if I could only get the engine working better...

2016 is the year all the B Series bikes because the same frame. So if you could buy a Felt B16 today for 1400 bucks it would be a great deal. And then drop $2k on components and you have a really great bike.
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Re: Triathlon Bikes in the Age of Peak Aero: here it is ;-) [kileyay] [ In reply to ]
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Excellent work! When does the planning for round two start? Trek SC, Canyon Speedmax, Felt IA, TriRig Omni, and Dimond.
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Re: Triathlon Bikes in the Age of Peak Aero: here it is ;-) [Fleck] [ In reply to ]
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out of curiosity, what is your spectrum of "insignificant" to "significant" in terms of "real world" aero savings and loss? i think this test provides validation that the differences between frames IS noticeable and that it simply becomes a cost:benefit equation when looking at bike purchases. the difference that kiley would see over a half-ironman bike between the fastest and slowest bike in this test means the difference between the fastest amateur overall and the third fastest. That's "significant" in my mind. Is that gain worth an extra 10,000 bucks?
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Re: Triathlon Bikes in the Age of Peak Aero: here it is ;-) [Dilbert] [ In reply to ]
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Dilbert wrote:
I'd just like to correct that a bit and say that all modern aero bikes are fast. Go back to a tube frame and that would test pretty badly. In fact it would be exquisite taking a steel tube bike and P5X into a wind tunnel to see the difference between them.

even here i'd quibble.

the rider still accounts for more drag than the bike. and there have been riders over the years who had incredibly good fits on round-tubed, steel frames (with aerobars and wheels, mind). and there are currently a lot of riders with incredibly bad fits on superbikes.

so the 'all else equal' qualifier that we usually put on these things is sort of nonsensical - 'all else' is never 'equal.' you need to fit well, you need to transport food, drink, and spares, you need a position that will allow you to digest, and to run well off the bike, etc etc etc.

____________________________________
https://lshtm.academia.edu/MikeCallaghan

http://howtobeswiss.blogspot.ch/
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Re: Triathlon Bikes in the Age of Peak Aero: here it is ;-) [jkhayc] [ In reply to ]
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Is that gain worth an extra 10,000 bucks?


If you are ONLY looking at the bike/frame then that's really only a small part of the story. The REALLY big gains with aero, my understanding is, is when you go all-in with everything else - wheels, helmet, apparel, and of course the biggest and most important - body positioning!


Steve Fleck @stevefleck | Blog
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Re: Triathlon Bikes in the Age of Peak Aero: here it is ;-) [kileyay] [ In reply to ]
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kileyay wrote:
This is really my biggest issue with the Andean. Everything from the steerer forward (including the steerer) and especially the stem.

if you spend a lot of time with a lot of bikes, this is going to be your complaint with the andean. the stem is absolutely fine if you cut off those "wings" that keep you from putting a different pursuit bar on it. right now i'm building up an andean and i've put a PD aeria ultimate with that aerobar's stem. looks pretty sweet. but i can't put the front storage on if i use that stem. so, problem there.

i would be willing to wager that a new stem is coming for that bike, then i think that bike - with a proper aerobar - will hit its stride.

kileyay wrote:
I think the jury is still out on whether the disc brake transition is on balance actually a good thing.

i wrote this two years ago. look at the FB comments at the bottom of the article, commenced by eric grill. and the corresponding thread. and then go back and look at your own results of your own tests. i wonder how long it's going to take before those of us who predicted the value of disc brakes on tri bikes will finally be vindicated.

Dan Empfield
aka Slowman
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Re: Triathlon Bikes in the Age of Peak Aero: here it is ;-) [Fleck] [ In reply to ]
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That's not really what the study showed if you read it. That's is what Dan suggested COULD be the case. As with most studies with limited funding and scope, often times the answers generate more questions. That would need more studying, which I don't think any of use are really wanting to do again without some financial compensation. We essentially did all this for free or in some cases at a personal coast. In my opinion the knowledge gained from the experience was well worth it for this one though.


Fleck wrote:
the best bike and the worst were separated by where you choose to place your hydration.


I've said this for some time - glad to see it backed up. That for the most part there really is not much difference between the best bikes. The ill-placement of a water-bottle on the bike has more impact on the aerodynamics than the frames themselves.

So could we also conclude that with the rather significant variable of riders-aboard the bikes (that has a much greater impact on overall aerodynamics) that really the differences in the frames are insignificant in the real world.



Heath Dotson
HD Coaching:Website |Twitter: 140 Characters or Less|Facebook:Follow us on Facebook
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Re: Triathlon Bikes in the Age of Peak Aero: here it is ;-) [Slowman] [ In reply to ]
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First of all, thank you to Kiley, Brian, Heath, David and everyone else who contributed to this ambitious project. Having been to the wind tunnel a couple times, I have some appreciation for the challenges they must have faced. It was also great to see involvement by Jimmy from Ventum and Dan from PremierBike, who were taking a risk by facilitating this independent testing.

Like others, I'm struck by how close together all the bikes are. As the report points out, four of the six bikes had essentially indistinguishable drag when accounting for error. I agree that, given the stated uncertainty, it makes more sense to view the results as two performance groups rather than a definitive ranking. Unfortunately, this may be difficult to grasp for those who haven't studied statistics. Kudos to the authors for including an error analysis (albeit limited, as they pointed out), which is too often overlooked in whitepapers.

In general, the test protocol looks sound, given the limitations of the testing (just 4 hours). My biggest reservation is that the Ventum was the only bike tested without front hydration. My own testing at the FASTER wind tunnel with Ventum showed a significant decrease in drag when adding front hydration. This is consistent with nearly all the other data I've seen; well placed front hydration (whether it's a standard, round BTA bottle or other system) tends to lower drag. The Ventum was likely penalized by testing without front hydration.

An alternate test protocol would have been to optimize each bike setup rather then attempt to standardize them. This would include finding the fastest position, helmet, clothing, wheels, fluid and storage options for each bike. This would have been prohibitively time consuming (Jimmy estimated ~6 hours per bike!), but more realistic and definitive. Just one example is that the Diamondback was tested without its integrated storage which would usually be in place, putting it at a disadvantage.


Slowman wrote:
there is nothing wrong with the ventum. this was like an 800 meter run, with 1st place clocking 1:42.68 and last place clocking 1:43.03. there were no dogs in this test. the best bike and the worst were separated by where you choose to place your hydration.

to wit, i *think* all the bikes had an aerobar mounted bottle except the ventum, which has on-board storage and much more than 1 bottle. therefore, if you placed 2 bottles on any of these bikes perhaps the ventum wins. now, the flip side of this, if you also placed a handlebar bottle on the ventum, this makes the ventum test worse (one assumes).

so, the ventum is either the best bike, or the worst, or somewhere in between, depending on storage and hydration preferences. this tells you how close all these bikes are.

(i'm sure someone will disabuse me of any error in my analysis.)

CodyBeals.com | Instagram | TikTok
ASICS | Ventum | Martin's | HED | VARLO | Shimano | 4iiii | Keystone Communications
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Re: Triathlon Bikes in the Age of Peak Aero: here it is ;-) [jkhayc] [ In reply to ]
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jkhayc wrote:
out of curiosity, what is your spectrum of "insignificant" to "significant" in terms of "real world" aero savings and loss? i think this test provides validation that the differences between frames IS noticeable and that it simply becomes a cost:benefit equation when looking at bike purchases. the difference that kiley would see over a half-ironman bike between the fastest and slowest bike in this test means the difference between the fastest amateur overall and the third fastest. That's "significant" in my mind. Is that gain worth an extra 10,000 bucks?

Depends on your perspective. If you can justify the Ceramic Speed derailleur cage at 500$ for 1 or 2 watts, then 5000$ for 10 watts is about the same (P5-6 or SC 7.5 for 2900$ frame. P5x is another level). You can point out that latex tubes are 2 watts for12$, but if you have done all the little stuff then bike frames at 500$ a watt are about the only thing left.

Me personally. I am looking at a "new to me" frame. Can't afford anything new until the kid is done with college.
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Re: Triathlon Bikes in the Age of Peak Aero: here it is ;-) [Cody Beals] [ In reply to ]
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Cody Beals wrote:
My own testing at the FASTER wind tunnel with Ventum showed a significant decrease in drag when adding front hydration.

interesting. i would not have guessed that.

Dan Empfield
aka Slowman
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Re: Triathlon Bikes in the Age of Peak Aero: here it is ;-) [Cody Beals] [ In reply to ]
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Cody Beals wrote:
In general, the test protocol looks sound, given the limitations of the testing (just 4 hours). My biggest reservation is that the Ventum was the only bike tested without front hydration. My own testing at the FASTER wind tunnel with Ventum showed a significant decrease in drag when adding front hydration. This is consistent with nearly all the other data I've seen; well placed front hydration (whether it's a standard, round BTA bottle or other system) tends to lower drag. The Ventum was likely penalized by testing without front hydration.

You should talk to Jimmy then. Since he was, uh, there for the testing. He could have asked that it be included, just like DK did for his bike. Or any of the manufacturers included could have requested.

"One Line Robert"
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Re: Triathlon Bikes in the Age of Peak Aero: here it is ;-) [Cody Beals] [ In reply to ]
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Cody Beals wrote:
Just one example is that the Diamondback was tested without its integrated storage which would usually be in place, putting it at a disadvantage.

If you hit a very narrow range within your fit, sure, you can use that storage. But the majority of folks wouldnt even have the option because of the way that front end is setup.

Curious if you read the whole paper?

"One Line Robert"
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Re: Triathlon Bikes in the Age of Peak Aero: here it is ;-) [Fleck] [ In reply to ]
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Fleck wrote:
the best bike and the worst were separated by where you choose to place your hydration.

I've said this for some time - glad to see it backed up. That for the most part there really is not much difference between the best bikes. The ill-placement of a water-bottle on the bike has more impact on the aerodynamics than the frames themselves.

So could we also conclude that with the rather significant variable of riders-aboard the bikes (that has a much greater impact on overall aerodynamics) that really the differences in the frames are insignificant in the real world.


To be clear, the best bike and worst bike might have been separated by where we chose to place the hydration. In the front. The hydration tests we ran with behind-the-saddle bottle configurations did not add a statistically significant amount of drag one was basically half a watt lower and one was one watt higher (confidence interval about +/- 2 watts).




Last edited by: kileyay: Jun 30, 17 10:21
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Re: Triathlon Bikes in the Age of Peak Aero: here it is ;-) [Cody Beals] [ In reply to ]
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That was a call made by Jimmy. We standardized the test for position, but let Dan and Jimmy make the call on optimal hydration since they were present. That's why we used the Profile bottle on the Tactical since he'd already tested it that way.

We've gone back and forth for weeks on this one, and we've basically said it is possible that that call hurt the Ventum. We have no way of really knowing for sure since we didn't test it with a BTA. Your data point adds another consideration to think about when looking at this data.


Cody Beals wrote:
First of all, thank you to Kiley, Brian, Heath, David and everyone else who contributed to this ambitious project. Having been to the wind tunnel a couple times, I have some appreciation for the challenges they must have faced. It was also great to see involvement by Jimmy from Ventum and Dan from PremierBike, who were taking a risk by facilitating this independent testing.

Like others, I'm struck by how close together all the bikes are. As the report points out, four of the six bikes had essentially indistinguishable drag when accounting for error. I agree that, given the stated uncertainty, it makes more sense to view the results as two performance groups rather than a definitive ranking. Unfortunately, this may be difficult to grasp for those who haven't studied statistics. Kudos to the authors for including an error analysis (albeit limited, as they pointed out), which is too often overlooked in whitepapers.

In general, the test protocol looks sound, given the limitations of the testing (just 4 hours). My biggest reservation is that the Ventum was the only bike tested without front hydration. My own testing at the FASTER wind tunnel with Ventum showed a significant decrease in drag when adding front hydration. This is consistent with nearly all the other data I've seen; well placed front hydration (whether it's a standard, round BTA bottle or other system) tends to lower drag. The Ventum was likely penalized by testing without front hydration.

An alternate test protocol would have been to optimize each bike setup rather then attempt to standardize them. This would include finding the fastest position, helmet, clothing, wheels, fluid and storage options for each bike. This would have been prohibitively time consuming (Jimmy estimated ~6 hours per bike!), but more realistic and definitive. Just one example is that the Diamondback was tested without its integrated storage which would usually be in place, putting it at a disadvantage.
[/quote]


Heath Dotson
HD Coaching:Website |Twitter: 140 Characters or Less|Facebook:Follow us on Facebook
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Re: Triathlon Bikes in the Age of Peak Aero: here it is ;-) [Cody Beals] [ In reply to ]
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Cody Beals wrote:
In general, the test protocol looks sound, given the limitations of the testing (just 4 hours). My biggest reservation is that the Ventum was the only bike tested without front hydration. My own testing at the FASTER wind tunnel with Ventum showed a significant decrease in drag when adding front hydration. This is consistent with nearly all the other data I've seen; well placed front hydration (whether it's a standard, round BTA bottle or other system) tends to lower drag. The Ventum was likely penalized by testing without front hydration.

I tend to agree.
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Re: Triathlon Bikes in the Age of Peak Aero: here it is ;-) [Cody Beals] [ In reply to ]
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Cody Beals wrote:
Just one example is that the Diamondback was tested without its integrated storage which would usually be in place, putting it at a disadvantage.

Who is defining "usually" for you?

Your protocol (/Jimmy's really) is just, honestly, ridiculous. Nobody is going to go to that trouble. The only tunnel where that's even remotely possible is at Faster, which is cheap, and doesn't have a completely reliable way of producing repeatable, accurate data.
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Re: Triathlon Bikes in the Age of Peak Aero: here it is ;-) [Ex-cyclist] [ In reply to ]
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Thanks for elaborating, Heath. Revisiting my 2016 data from FASTER, I saw a 40 gram reduction in drag when adding a Torhans Aero 30! I wonder if Jimmy is regretting that decision to test without front hydration... In any case, nice work.

CodyBeals.com | Instagram | TikTok
ASICS | Ventum | Martin's | HED | VARLO | Shimano | 4iiii | Keystone Communications
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Re: Triathlon Bikes in the Age of Peak Aero: here it is ;-) [Cody Beals] [ In reply to ]
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why don't you use it? looks like you wouldn't be able to get it close enough to your head tube?


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