Is mounting computer on stem more aero than out in front?

Discuss light weight issues concerning road bikes & parts.
Shrike
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by Shrike

Spotted this on my travels,

"Cervelo claims that mounting the Garmin on top of the stem is faster in a wind tunnel than out in front."

http://www.bikeradar.com/us/road/news/a ... 015-42254/

1415chris
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by 1415chris

Not having widely available front mounts for Cervelo aero bar on the market, I'm not surprise that they came with this statement :)

by Weenie


itguy
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by itguy

1415chris wrote:Not having widely available front mounts for Cervelo aero bar on the market, I'm not surprise that they came with this statement :)

+1

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Marin
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by Marin

Mount it to the top tube behind the stem.

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Stolichnaya
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by Stolichnaya

Not sure about the aerodynamics, but out front is easier to read when going fast and arguably safer; that counts for something.

Shrike
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by Shrike

Aye, they would say that wouldn't they! :P

Out in front also looks better to my eye.

gewichtweenie
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by gewichtweenie

dat insane +2cm^2 of frontal area....

Stolichnaya wrote: but out front is easier to read when going fast and arguably safer; that counts for something.

agreed

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kgt
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by kgt

Underneath the saddle is the most aero. Aero rules! :thumbup:

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BRM
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by BRM

Another bullshit Cervelo claim.

Take everything from Cervela with a grain of Salt.

CrankAddictsRich
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by CrankAddictsRich

Rather than just make a claim, Specialized put it o the "win" tunnel test.

https://youtu.be/emBR0gOb6oE?list=PLcmaLnqmqDnmn_bCR0RJ-soSCDKCKR97t
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kgt
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by kgt

So Cervelo's claim is scientificaly proved BS. Good.

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mortirolo
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by mortirolo

Specialized used 17 degree stem in test, I think.
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Shrike
Posts: 1133
Joined: Fri Jun 03, 2016 5:08 pm

by Shrike

Okay so bullshit then, thanks for the vid!

Got the bike home today and was dying to get some sort of ride on it. Couldn't get the mount on the stem, no band long enough. Got it on the bar though and found a Lezyne light that was stretchy enough to go over the bars. Sun had set so wanted some blinky thing.

Have a posh light like Strada MK7 and posh K-Edge mounts for Garmin, and GoPro. All useless!

This is my current setup :|

Image

ryanw
Posts: 327
Joined: Sat Apr 16, 2016 6:52 pm
Location: London

by ryanw

Same as mine:

Image

I'm seriously contemplating changing to an Enve Aero bar and stem combo due to their out front mount looking so sleek...
'16 Cervelo S5 - 6900g
'17 Focus Mares Force 1
'15 Scott Addict Team - 6850g Sold
'17 Cervelo R3D DA - 7580g - Sold
'16 Cannondale CAAD12 DA Disc - 7560g - RIP

by Weenie


CrankAddictsRich
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by CrankAddictsRich

kgt wrote:So Cervelo's claim is scientificaly proved BS. Good.


yes and no... I'm not an aero expert, but I do a fair bit of TT racing, so I pay attention to the aero tests and from what I gather, anything out front, in the wind, in clean air, has a pretty dramatic effect, while stuff toward the back of the bike doesn't seem to be as important because the air is already seeing a lot of turbulence. Here's how I analyze their claim.... let's assume a standard baseline bike, a general, all-around climbing bike, maybe an R5 with a standard round bar. Then, Cervelo designs the S5 with their handlebar/stem combo and that set up improves the aero over the baseline by 3%, putting the Garmin on stem (because an out front doesn't quite work) doesn't negate that 3%, maybe it only knocks it down to 1.5%. So the bar stem combo still puts you ahead in the aero game even if you do have to mount the Garmin on stem.

mortirolo wrote:Specialized used 17 degree stem in test, I think.


Yes, the bike being used is Cam Piper's personal bike and it appears as if he's using a -17* Zipp Service Course SL. Specialized has stated in numerous materials and aero reports that a -17* stem is the most aero because it puts the entire length of the stem behind the faceplate, shielding it from the wind.... its because of this, that they came up with the rider handlebars for the Venge Vias, allowing for riders to keep the same fitment with a -17* as they would with maybe a -12* or -6* stem and standard bars.
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