What would you do to upgrade the P5's stock Aduro cockpit?

So is it 1 specific wheel that equals disc brakes?

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Brooks Doughtie, M.S.
Exercise Physiology
-USAT Level II

I think everyone should just buy the bike that makes them the happiest. Whether that's a p5x, Felt B series, speed concept, andean, whatever. Buy the bike that you lust over and can afford at the same time.

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blog

No.

So which rim brake wheels are near equal to disc brakes. I had assumed that it was common knowledge discs are a better braking component (that's accepted as industry standard yes). You've given me 1 specific wheel, what are the others?

I just bought a road rim brake bike, I won't go to disc brakes likely for 3-5 years.

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Brooks Doughtie, M.S.
Exercise Physiology
-USAT Level II

I find that alu rims with the right pads are every bit as good as disc. I'm sure they have their place, but I haven't found it yet (on road bikes that is).

What road bike did you try on disc brakes?

ETA: I was listening to Lance's new podcast with Tour stage recaps and he spoke about 7 mins on disc brakes and just how the industry is going about changing to them. He said he won't ride on rim brakes anymore (he still has bikes w rim brakes), and spoke about how industry is pushing forward with this whole disc brake movement.

FYI his podcast is actually really good on recaps. About 30-40 min daily recap. He's gotten much better at podcasting since he started. I don't listen to much of his regular podcast but he's getting some viewership.

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Brooks Doughtie, M.S.
Exercise Physiology
-USAT Level II

I think on a racing bike (road and tri) they are just not required but all other bikes for sure why not. I think there is a market for discs but not all markets need them. The problem is that the bike industry needs planned obsolescence every 5 years to sell more product.

Everyone please buy disc equipped bikes and when you need to offload your non-disc equipped wheel and frames please keep me in mind.

Pretty much. I can't see any reason to change TT bikes within the next decade.

You shouldn't feel sour. You should just sell the aerobar and stem for something good. That's literally all you have to do.

You should have guessed that, because you've been around long enough to know where the problems bits are.

Putting a bottle up front does a number of things:

1. Fills the gap so that wind has to go around the shoulders and misses the seatpost, which in this case, is very non-aero.

The clamp and seatpost head design can be improved by 2-3 watts across all tested yaws, which would improve the bike greatly in frame only testing, or when the bottle is missing.

2. Fills the gap and pushes a bunch of air away from the absolutely abysmal open mold aerobar. This is like strapping a sheet of plywood to the front of your Ferrari. Yeah, it'll still go fast, but that's a testament to other factors. The bad part is still holding you back.

Now, it's absolutely position sensitive, but in my experience should work perfectly with Kiley's position. Same for the Andean. Both of these bikes suffered because of the front end setups.

My personal opinion is that this kind of testing gets a lot more interesting when you move away from the stock components, and build for "absolute best". IMO, that usually means put a Ventus on it. Or a TriRig.

Did anyone mention that the Ventum might be more aero "riding it" backwards? (just for a tunnel test, put the front wheel on the rear, bars where the seat would be etc, spin the bike around )

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Training Tweets: https://twitter.com/Jagersport_com
FM Sports: http://fluidmotionsports.com

It might just be you and I thinking this, but I really doubt it.

I've got $1000 for anyone willing to go into the tunnel with a P5x and an Andean that will test them head to head, rider on, with and without the brakes. I'll even supply a set of aerobars for the Andean that don't suck.

What this is going to show you is that there are a couple of bikes that are head and shoulders above everything else that is made, but that they are being brought back to earth by the brakes.

Don't argue that you can't ride the bike without the brakes, that's not the point.

I'm there July 11.

Get me the bikes, cover tunnel time and I'll do the tests. I've got an athlete there that day and can (probably) convince him to be the rider.

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Brian Stover USAT LII
Accelerate3 Coaching
Insta

So which one do you believe is the fastest?

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Make Inside Out Sports your next online tri shop! http://www.insideoutsports.com/

For me, I believe the P5X without brakes would be the fastest. I have long legs, and have always found that I benefit more from beam designs than other people with more normal proportions.

That said, with a new front end, and a couple of other bits hacked off, I think the Andean wouldn't be too far behind.

I could also VERY easily get the Ventum into the same range with a new aerobar, fork, and a TriRig Omega.

The point of being willing to spend $1000 is so that someone else takes care of those details.

I don't own either bike, because I believe that they are moving in the wrong direction, and making compromises I'm not willing to spend money on.

Besides, I already have this, and it's the fastest bike for me.

If the bikes are making compromises you won't spend money on, then why are you wanting to spend $1000 on testing them? What compromises?

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Make Inside Out Sports your next online tri shop! http://www.insideoutsports.com/

I'm willing to pay $1000 just to settle the argument. I don't have any doubt about the outcome, but people here seem to just not get the picture.

The question isn't "How do we make a disc brake bike that is faster than our current non-disc bike", it is "How do we make the absolute fastest bike that we can."

There are clearly 10 or 15 design elements of the P5X that clearly show Cervelo knows how to make a fast bike. Most details are handled exceptionally well.

Compromises for me are: Disc brakes, which means new wheels for many consumers (Both). Crappy seatpost head and saddle clamp (Both). Crappy handlebars (Andean). Wallet storage makes for poor trailing shape (Andean). Artistic fin below the BB and the corresponding parallel line above the BB in the main triangle (Andean, aesthetics do not overpower aero)

Honestly not a lot of negatives for me on the P5X. I would probably own one if it came sans discs.

Yeah, but how adjustable is the seatpost? What if the seat's too high?

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'It never gets easier, you just get crazier.'

Thought my positions was pretty dialed in. But then I saw this and now I'm worried :"If you hold that far down the bar you're probably doing it wrong"

Um...where should you be holding the bars?

Faster for whom? An age-grouper in a 70.3? A pro at Kona? Taylor Phinney in a technical 40K TT (ignoring UCI rules)?

Those might all be different bikes.


Why do you think disc brakes are slower? I think, if operating from an evidence-based standpoint, it's becoming increasingly difficult to make the case that disc brakes are an aero compromise.

Also you, in general, seem to be operating from a more eyeball-evidence standpoint. HED Corsair "crappy?" You can eyeball gauge the optimal trailing shape on the Andean? Really?

I think one lesson from this exercise is that eyeball windtunnels suck. Slowtwitch got it wrong on the P5X. And I've yet to see much humility on that front from all the people who just knew it was "slow."

Up by the shifters - means you don't have to move to shift and it's easier to get a bit of upwards angle to the hands

All those holes allow you to move the seatpost up and down. Not rocket science.

Once you get the height right, you take some measurements and print up an actually aero cover that hides the holes and the flat sides of the 5.5mm wide post.

The reason that I know for 100% certain that discs are slower is that you can hide rim brakes inside the existing frame dimensions and not increase drag at all, while there has been no attempt to hide the disc brakes on either the P5X or the Andean. They have drag. Some drag is more than no drag. Pretty sure I've got that bit down.

RE: Eyeball wind tunnel

I don't have one of those. I have Solidworks with the CFD package, and a monster dual 8-core Xeon server to run it on. I run simulations pretty much constantly. Enough that my house generally does not need to be heated by the furnace during the winter.

So yes, I can tell you what the optimal trailing edge of the wallet is. I can also tell you that it will no longer fit a wallet. I can even tell you the number of grams of drag (at any speed and yaw you want) that you can reduce on the Andean by strapping a proper aerobar on.