IM saving P2 vs PR6

I would look at it slightly differently.

You say 10min is worth "it". What is "it". $1500, $1000....?

Is the frame the best $1500 spent? Probably not but that will depend on how you are currently setup, what you wear, your helmet....

Many people will get a few watts from the frame but dozens of watts elsewhere.

If your current frame does not fit, then that's a completely different story.



Edited by marcag 2016-03-05 2:51 PM

P2 is a solid frame - no way the PR6 is that much faster, even over an IM, especially if the cables are nice and clean on the P2 and bottles and flat kit are in strategically aero spots. Put a TriRig front brake on the P2 and tidy up things rather than throwing money at a new frame. If you don't already have a power meter, invest in one.

I'm surprised you think there is negligible difference between a $5k "super bike" and my P2 which you could pick up for under $1k. Don't you think there are weight / stiffness benefits as well as aero design / cabling etc? Also wouldn't it enable a more aggressive fit?

For me it's worth the $5k if it gets me 10 mins.... As obviously in addition to this 10 mins In this race get a nice shiny bike which I can race faster in all other races...

Worth more than at most a handful of seconds over 180km - no.

Shane

Through testing you can easily find 10mins for an IM. Very easily.

Look at the aero numbers of the PR6. They are good, but a well equipped P2 could probably come close and a proper position, helmet and suit would buy you much much more.

I went through this exercise with the help of some really smart people. I have a P2 (2009) and a BMC TM01. I can get them almost identical and my BMC is probably the same as a QR according to independent tunnel testing.

If fit is an issue on your current bike, that is a completely different story. But there are usually ways to address fit. And BTW, you could buy a brand new QR. think you are getting super low, only to find out through testing that your original bike, with a better head position was faster.


What I would do ?
Go out and test. If you are a .29 cda which many many people are, then stop thinking bikes. You have a TON of low hanging super cheap fruit.

If you are a .195, go out and shop for bikes.

Edited by marcag 2016-03-06 7:48 AM

Hit submit early - rather than editing, I will address this here:



Maybe. And you also need to determine whether more aggressive for 180km and then a marathon is what you need. A great position through 100km and then sitting up for 80km is going to save you no time.

For value, I'd look to upgrade your frame if you've taken care of everything else. Helmet that's good for your position, sleeved fast skinsuit, cleaned up all cables, cleaned everything you'll carry to be as aero as possible, disc rear, deep front, great tires, latex tubes, etc.

Shane

Marc and Shane are spot on (as always)

to echo though...

If the P2 fits good, then a PR6 isn't "worth it" by your definition. Take the $ you were going to use on the PR6, buy a smart piece of clothing (sleeved top that fits well) a "generally well testing" aero lid (giro's, P09's, Spec TT's all seem to do well on a range of people) a disc wheel or cover and deep enough front wheel as you can handle, smart tires/tubes, and if you are still feeling spendy a slick cockpit and some aero brakes. Get your cable routing smartly done (maybe try the tririg "hack" of giving it behind the stem routing)

Do that, and you'll have $ in your pocket still and be faster than you would be on the Qroo.

All that based on the assumption that your fit on the P2 is tight (or at least can be achieved on it) if that isn't the case, then yeah, new bike time.

I threw together this chart just to illustrate things.

The average person's cda is probably .35 and the potention optimization is probably broken down like this

You can't get below the black bar

As you can see, the contribution of the super bike to regular tri bike is pretty low. There are lots of much cheaper lower hanging fruit.
These numbers are a combination of data from white papers, personal experience testing and watching other people test and just ball park. We could have debates on each

The P2 is probably at the edge of good bike and super bike
The QR is probably in the middle of super bike

at 180w, the difference between a .35 cda and .20 is about 5h26 vs 4h34 over an IM







Edited by marcag 2016-03-06 9:29 AM






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Many thanks for the info. Its very interesting and worth a thought. Based on this I should be looking into clothing. The thing with all these charts is that you never know where you sit on the scale before starting any upgrade... It looks that clothing and helmet are the big (and cheap ones).

Eg I race in a Desoto Liftfoil 1 piece tri suit and a Giro Aero Advantage A2. Unless I know where these lies its difficult to know whether its worth upgrading or not...

One question, what does eyeball fit mean?

Eyeball fit is posting some pictures on here and having the peanut gallery tell you your seat is too high. (Or something like that)

Giro A2 is a pretty safe hat to be wearing. It's not usually the fastest helmet people test, but it's generally "good" for most people, which is to say it's one of the better "guesses."

In regards to clothing... the sweeping rule of thumb is to cover as much skin as possible. A race suit with sleeves *should* buy you a some time on the bike, but you need to figure out if you can swim in it comfortably or, if you plan to put it on in transition how much time you will lose in T1 getting it on vs. how much faster it will make your bike split. There are quite a few options out right now that are full sleeve, and with the rules change allowing them in all races there should be many more in the coming months.

As Chris mentioned, eyeball is the very obvious stuff you see just by looking at a person's profile picture where they are sitting up like on a road bike with their head way up there. People don't have a good appreciation for how much time they are wasting which is unfortunate because they may have spend a lot of money to get a 3w aero saving on their wheel and are losing 50w because of a silly position.

A person that is in a reasonable position is under .3 to start.. That's what that big blue block is

For clothing it's amazing what a difference it makes. I have seen it with my own eyes twice where a DeSoto Forza tight fitting one piece was SIGNIFICANTLY slower than a LG skin suit. I didn't believe, went back and forth and confirmed. A lady in your area, road tested those two and also found a significant difference. Most people coming out of aero camps will tell you their biggest savings was on clothing. It's very significant.

For helmets, a lot of people repeat that the A2 is a good helmet. My only comment is make sure the straps are well laid out.

There are many wives' tales about aero all the way from you can't test without a wind tunnel to lower is always faster. Going to watch an aero session is an eye opening experience where many of the myths get disproved pretty quicky and where you think the result will be X and it's the complete opposite.

The only suggestions I can make are a) learn to test b) if you are not going to test, use independent data (not from the manufacturers) c) focus on position first

Take old race photos and pick them apart

Just wondering.. how easy is it for you to breathe with a -17 degree stem? in my mind I see you crumpled up like a ball haha

Lots of good stuff already said.

If you list your components, these guys will pick them all apart and let you know the good and bad.

Something I did 2 years ago, was shortened my cranklengths. By doing this it opened my torso so I could breath easier. When you shorten the cranks you also have to raise the seat, which put me in a more aero position. Also with shorter cranks I am able to spin faster, since I generally do not spin fast this was a benefit to me.

The degree of the stem is probably not a good indication of how low he is, how tight his hip is or how crumpled he is. The drop from seat to pads probably is a better but not perfect indicator.

His seat may be low, his bike may be big, the stack of his aerobar may be high. A different bar/pads are one way of getting lower when you run out of spacers or can't go negative stem.

x2. It was really good for me.

I watched them fit Lionel Sanders a month or so ago. That's what they did as well. Dropped him to 165s.

Here I am. How do I look??





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You are leaving tons of time on the table, much more than what a new bike would buy you without position changes

Your head position is of course the most obvious
You look like your jersey is open and a small parachute
That botttle on the front is bad
Your arms are tilted down
That bag on the back can be a drag
Bento box could help
Maybe the bottle on the downtube. Put it behind your butt since you have an aerobottle. But first get a good aero bottle :-)

For a few hundred bucks you could be WAY more aero than you are now

IF, big IF, your position would allow it, you could go lower in the front with a different set of pads
You need to analyze your position first on top of all of the above

Lots of low hanging fruit for you.
Do you have a power meter ?

Edited by marcag 2016-03-07 8:47 AM

I went from 172.5 to 165. Now that I did it I think I could have could have gone down to 160 or 155 and been a little better off even. I think this is an understated improvement that many people still argue.

^this

The bike isn't holding you back.

Thanks, for the advice. I should have mentioned this before but since this race I have changed the front bottle to a BTA one and removed the one on the down tube. I changed my arm position up a bit. I've move the spares to a bento box up front and removed the wing.

Head position is an issue. I've now got a Giro Air Attack shield as I find it hard to keep my head up enough to stop the tail acting like a sail...

What are your thoughts on the fit though (seat height arm position etc).

I have a power meter.

The bike looks much more like this now, except I now have FLO wheels and use a bento box instead of the x-lab wing and bag thing behind my seat...

Edited by Stimps 2016-03-07 9:15 AM






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I feel I would be able to go lower but I can't work out how.. I can't see how a different set of pads would get me much. The only Thing I could think of was an even more aggressive stem...

ritchey makes a good adjustable stem (I've used it on many of my bikes) very secure. Also pretty cheap.

3T bars are all fairly high stack even in their lowest setting (besides the mistral I suppose)Visions or an old alloy Felt bar would give you a little bit.

Part of keeping the head still is fit, part of it is practice. If you don't spend a lot of time in a fast position you'll never be able to hold it on race day.

The air attack is almost certainly worse than the advantage even with the tail sticking straight up in the air.

What kind of tires and tubes are you running on the FLOs?  Looks like you're running tubulars on these, with one of them being a gatorskin.  If you aren't already running fast tires, latex tubes, and a disc cover (assuming you don't have a FLO disc....start there.  Those are easy, cheap, and you don't really need to test.  Could amount to over 10 minutes by themselves depending on what you're using now. 

Edited by Jason N 2016-03-07 9:41 AM