Keep the 404s and get a disc cover. Easier and definitely cheaper.

Which 404's? Might not be any advantage to move up to an 808 but a disc cover on the rear is a great addition.

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Rodney
TrainingPeaks | Altra Running | RAD Roller
http://www.goinglong.ca

+1

You could go deeper in the front and add a disc cover in the rear. The model year / generation of the 404s would obviously be a thing to consider now that they've had Non FireCrest, FireCrest and FireStrike models.

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"Train so you have no regrets @ the finish line"

If you are < 1 minute away from reaching a goal and have lots of money, then yes it *may* be worth it.

Generally, I'd say it's not worth it. As someone else said a disc cover is probably a good option for you.

You could also rent a zipp disc and 808 for one race and if you have a transcendental performance, then buy them?

Depends totally on the athlete. Can you maintain 40k/hr + steady over the race course? If not, disc may be a bit detrimental. "Faster", generally yes. But it's the same for people who have carbon wheels and can't ride 32k/hr, it's really not doing anything.

You could ride aluminum clinchers with the best hubs money can buy and be just as fast! It's not always about the aero fairing, but how the wheels spin up over hills/etc.

I saw 404's w/ Disc Cover above, I'd recommend that before investing full on in a disc.

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Carson Christen
Sport Scientist / Coach
Torden Multisport

Have been reading ST for a while and just about every time someone brings up this old canard.

There is a benefit to riding a disc at any speed except backwards.
Repeating the 40kph legend just shows that perhaps your specialty is not bikes.

Um....show me that proof?? Where say a 125lb man or 100lb woman will be faster riding a heavier disk than something lighter and spins up faster.......

You might want to look at who you're attacking with your claims of not being "intelligent" about the cycling community. I'll pass my resume over to you if you need correction.

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Carson Christen
Sport Scientist / Coach
Torden Multisport

http://flocycling.blogspot.ca/2012/11/flo-cycling-cycling-wheel-aerodynamics.html


Aside from the opinions of people like Jackmott and a few others who post on here, that say the same thing over and over again. A disc is better at any speed. Notwithstanding your excellent credentials.


Wander through the site above and, if you like spend, a few minutes on google with the basic question "advantage of disc wheel at any speed".
I should point out that I did not use the word intelligent, the word I used is specialty. I would expect someone who gives advice to know the difference.

Why is FLO Cycling 100% accurate? What about these two sites on disc covers vs open disc?

http://www.wheelbuilder.com/aerodisc-data.html


http://www.codybeals.com/2014/03/asktrinerd-disc-covers-vs-real-disc/


The later from Cody Beals who is a science-geek and great racer. But look at his conclusion. "It depends" You can't take lab data and say it's accurate for 100% of the population. Hence my advice to look at different, cheaper options. If someone can save $1500 on an aero cover, and invest that in coaching / testing / to make them physiologically faster, why not do that instead of buying a $2000+ disc.


You're saying Daniela Ryf or Chrissie Wellington would have been so much faster on disc wheels? How about Kienle. Is he stupid for not riding a disc always?

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Carson Christen
Sport Scientist / Coach
Torden Multisport

When has Kienle not run a disk, other than Kona when it is not allowed? Also Ryf has a coach that does not allow his female athletes to run a disk because it beats them up too much, even if it is a HED disk that is actually a spoked wheel with a cover, because he is crazy.

Maybe bad example. I'm not trying to be really defensive, just as to why there isn't an agreement on everyone is different. Devils Advocate :D I can't and won't disagree that discs are faster, but in "EVERY SINGLE CONDITION", I just don't see how you can make that assumption.


What about Tim Don?? I don't know if I've ever seen him ride a disc? Ironman Mallorca and such, he rides deep wheels only. Is he stupid for not riding a disc** (Better reference)


https://www.facebook.com/trithedon/photos/pcb.1494119010842754/1494117650842890/?type=1&theater

Romain Guillaiume, C50 or C75 at Ironman Nice? And beating guys who rode discs.

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Carson Christen
Sport Scientist / Coach
Torden Multisport

As to what? Just show me where someone will be faster on a disc at Ironman Mallorca or France or Lake Placid who rides at 150watts. The whole argument is I've been told it is faster in ALL CONDITIONS.

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Carson Christen
Sport Scientist / Coach
Torden Multisport

http://velonews.competitor.com/2012/06/bikes-and-tech/technical-faq/technical-faq-does-wheel-weight-matter_223209


While this is worth reading, considering your remark about "spinning up" and lighter riders.


My original response was regarding your assertion that the disc is of little value unless you are riding at 40kph, when that's just patently wrong.
This is a line that gets repeated time and time again, without foundation.


As for a disc cover over a full disc, there's no doubt there is precious little difference, I didn't say there was. I ride a disc cover, because it's a $70 solution.
They both work (disc or cover) essentially the same. At any speed, they are faster.


Why did I use Flo ? well mostly because we (on here) already know them, they are engineers, math is not their weak point and they have, if you scroll down a nifty set of charts that show the advantages from 1mph on up to 30 of one specific wheel, their disc, over another high quality, superb, light wheel. And the greatest difference is at slower speeds (which may answer your question about what pros ride)


As for what pros ride, we all know that on occasion they have priorities that affect frame, wheel choice, helmet, suit, and nutrition etc.
They are, in the main, from a different world than the rest of us.


(And Chrissie would have been faster on a P5 I have no doubt, with or without a flat)

Maybe why everyone company comes out with new wheels / disc covers / research every year. Hard to know. And I guess I was just making a moot point, not that 40k is the assertained speed. Agree to disagree on companies and speeds of affect :D

I always think it's funny when riders show up and beat full aero setups on training wheels. Just makes an argument why I feel most athletes could benefit way more from coaching than trying to "buy" their speed, even though that can happen to an extent. So of course I'm trying to sell my services!

At least we both agree Chrissie should have been on a P5!

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Carson Christen
Sport Scientist / Coach
Torden Multisport

I was curious what Best Bike Split would say about this. I plugged in all my variables (145lbs, 235FTP) using the fairly hilly IM Canada course (~6000ft) with an 808 (already have) and disc. Surprisingly, it came back with the disc being a whole "1 sec" faster. It was more for my curiosity, but needless to say I'll be going with my 808 rear in 3 weeks.

I agree there are some instances where is disk is not faster, but those are very very rare triathlon courses (Alpe D'huez, Norseman), but where I would disagree the most is using the riders average speed over a course to determine if a disk should be used. I would first look at the course profile. Second spin up of a wheel is very meaningless especially for a triathlon or TT. Not only is its total effect very small, generally you hit a climb either from a flat or descent, so the inertia actually does help you a bit, not to mention the disk would mean you hit the climb going slightly faster in the first place.

Are those athletes silly for not riding disks? Honestly maybe. Many pros do not understand equipement and if they are winning it is even harder to convince them they could be even faster. Or maybe they have sponsorship issues that influence the choice, it may make sense to maybe get a bit more money to run sub optimal equipment or save some out of pocket money that can be better used on something else, because a disk is many times only a small advantage over deep section wheels. Most importantly disks sound awesome, so it is silly not to run one.

WOMP WOMP WOMP WOMP.....you are right about the sound.

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Carson Christen
Sport Scientist / Coach
Torden Multisport

Yes, most people could benefit from good coaching versus buying some fast equipment, but you came into this thread with the assumption that people can not do both. There is no indication from the original poster or anyone else that they were not also going to train. In fact if someone is trying to optimize their performance they would be training well AND asking questions like this.

Why is that funny? That athlete would be even faster if he'd paid attention to the equipment he's riding/using. Also, what are training wheels?

Why would someone be interested in your services if you can't see that being aero/using aero products and optimizing your training are not mutually exclusive?

This is all moot any way. The rear wheel would be the last place I'd look for "free speed".

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"One Line Robert"

He has a Transition - Wheel Builder cover is not an option (normally, it can be made to work sometimes, but it's a PITA).

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"...the street finds its own uses for things"

I never said that..... I believe aero is very important, it just depends on the athlete. I didn't say there was an overlap or that one can get the same not using the other. But more gains are made with fitness than aerodynamics in most long course races.

So you need to optimize both. My example on athletes showing up with full aero or not full aero...... I know the guy didn't train hard, but "bought his speed" and was trumphed by somone who trains very hard but wasn't aero. Similar athletes. It was a training race, he doesn't have aero wheels yet. Of coures he would be even faster had he used aero equipment.

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Carson Christen
Sport Scientist / Coach
Torden Multisport

What did you use for winds? At zero yaw (light winds) I've found the difference between a disc and my jet 6 rear to be negligible (according to bbs), anywhere from one to three seconds - even over 112 miles. If the winds are strong enough to generate higher yaw angles you will see the disc start to outperform deep wheels. For me if the winds are light I don't bother putting the cover on. A whole new thing that was suggested to me once that might change things is that sidewinds on a disc does dramatically reduce your drag, but apparently the side loading on the rear tire increases rolling resistance. Anyone else heard that theory?

I would get a wheel cover. You should put all your stuff into best bike split and compare a disc to a 60mm