brianappleby

Mainly the lower end:

S22 vs. P2SL/P1

B-16 vs. P2C

I can't try the felt before buying, so I'll compare geometry charts w/ the actual fit of the Cervelo.
I can get a slightly better deal on the Felt than the Cervelo.

Weight doesn't really matter to me, aerodynamics/price do.

This is mainly for shorter TT's, It'll be my first and probably only TT bike.

Thanks for any thoughts.

B.

ridethecliche

Are there any wind tunnel tests for the Felt?

My point is simply that you know what you're getting with the cervelo unless data exists on the felt.

Just my $.02

Trekke

I would get the Cervelo. You wont be looking back wishing you had for just a few dollars...

Racer Ex 

Brain,

Look at the P3 aluminum. Very good tunnel numbers, and if you're doing shorter TT's the better ride quality of the carbon bikes won't be worth the trade off in aero effeciency. P3's near the top at zero yaw, and a lot of the frames that are close fall away when you move the yaw from zero.

skinnyone

They both support arguably some of the best TT pros. I'd go with the one that fits your budget.

flyguy676

I use to have a Felt tt, the s22. i loved it. felt makes a good bike!

furiousferret

Get the Felt, if you get a Cervelo it will get lost with the hundreds of other Cervelo's at TT events.

brianappleby

Originality doesn't mean much to me. Speed does.

I've been looking at aluminum P3's, but people don't like to let those go for less than a carbon P2, and although it may be faster, used aluminum is a tough choice over new carbon.

Thanks for the advice.

furiousferret

Neither frame is going to make you any faster, if anything buy what has the better wheelset.

brianappleby

Already have a decent wheelset.

tekhna

The difference between the two is pretty negligible once you put a rider on it. I'd get the Felt, it's probably cheaper.

tanhalt

If it's a choice of those 4 frames...P2C in a heartbeat. It's been shown to be only slightly slower than a P3C (if that) and all other things being equal (i.e. position, other equipment, etc.) it will be measurably faster than the other bikes you list above.

Hands down the best "bang for the buck" (aerodynamically speaking) out there.

Val23708

cervelo

jrennie

One would be foolish to think that felt/time/look/spec/giant/fuji/ridley/etc/etc don't all go to the tunnel and have test data on there frames. The question is if they do it before or after production, if they do it for ad photos or development. Wind tunnel test can be manipulated to show many different results and different frames/components to be faster than others. Cervelo likes to say they are flattered that in every published tunnel test the come in second to whomever paid for the test. I think there is some truth to that.

BikeIndustryGuy

+1, wind tunnels are the most abused devices to sell bikes and parts. Unless they compare bikes with the same mockup rider dummy, in multiple runs, across multiple days, comparisons are rather pointless. No one does this. Cervelo uses a mock up dummy, but it's still data provided by a company selling the bike (which still amazes me that people swallow up in droves, especially in forums).

It's very easy to skew tunnel data with the slightest position change from the rider. This is because in the total package, rider position has more of a real effect than any frame or wheels.
At this level, you need to pick a frame that will give you the optimal position, if you can't figure that, go for the best price and with what you like.

asgelle

Maybe because some of us are experienced at examining data with a critical eye and can differentiate between what is meaningful and what is not. For example given the lack of coupling between frame and rider, adding a rider only adds noise to the system and makes it harder to elucidate the difference between frames. As to repeating runs on different days, unless you believe the phase of the Moon or the gravitational pull of the Sun affects the results, I see no benefit to this.

skinnyone

True. Is the frame is a significant portion of total drag? Does anyone know? Curious.

Intuitively it seems to me that it would be smaller component of total drag when compared to the rider ot the wheels.

jrennie

Of course the frame is a smaller component of total drag than rider, as is the helmet, suit, wheels and everything else but drag is drag and if it can be reduced to net the rider the same time on say 45w less then it becomes a big component.

skinnyone

I guess my thinking is that we are talking small deltas between small numbers. Just the frame alone that is.

asgelle

John Cobb puts the difference between a good aero frame and a moderate one at about 1 minute for a 40 km TT when the rider produces 200-300 W. https://www.amazon.com/High-Performan...8269949&sr=8-1

wfrogge

The P2c is one of the top aero frames (wind tunnel data) out there except for the P3/P4. If you can find one at a deal the P3 SL (alum) is just a tad less aero but way heavier than the P2c.

I had the same issue trying to find a "cheap" P3 SL where the seller wanted 800-1000 for the frame. By the time I built it up the cost was only a few hundered less than a P2c. I went with the P2c