Most aero position for out front Garmin mount?

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neeb
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by neeb

Is there a consensus on what the best angle is to have your Garmin positioned with respect to the stem if you are using a mount such as the raceware one, which places the Garmin in line with the stem?

The most obvious thing to do when you first fit this is to have the Garmin precisely in line with the stem, in which case for most of us it is sloping upwards from the horizontal at about 6 - 10 degrees. This is also the best for readability. But will it be more aero if it is pointing horizontally and so presenting less surface area to the wind? This would seem to be obviously true, but I wonder if there are complications to do with air flows or whatever.

This may seem obsessive, but it is sticking right out in front after all, and if front brakes and cable routing can make a big difference then presumably this can too.

I assume there's no doubt that a mount such as this is more aerodynamic than having the Garmin in the conventional position on top of the stem?

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DMF
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by DMF

I reckon there is a matter of turbulent wind whipped up by the front wheel, which will not look a like for all different front wheels, and also how the wind acts behind the and close to the Garmin unit. Also different mounts look a little different even if the computer is in the exact same place, so bar/stem/mount will come into play.

Most likely answer, there is no definitive answer unless you wind test every single different scenario. And also, for the considerably largest part of your riding you are facing the wind at yaw angles. And those are for the better part larger yaw angles than you think due to the movement of the bike in relation to actual wind angle.

Easy answer, you will never find the actual answer to this one. Want aero Garmin? Make a fairing.

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aaric
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by aaric

There's always this:

Image

Biggest gains would be keeping the garmin level enough that it doesn't create a larger frontal area - so tipping it up above the bars it probably bad. However, any gains made there would have to be combined with whatever position modifications you'd make to use it.

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Calnago
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by Calnago

Seriously? As I sit here sipping a glass of wine, I almost spit it up. If you can tell a difference in aero between a Garmin mounted in line with the stem (looks the best and easy to read as you mentioned) and in its most aero position (straight ahead into the wind) then bully for you. I'm sure you'll get some more useful answers than this. But i don't think you'll notice a difference either way.
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Kayrehn
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by Kayrehn

The integra stem doesn't look like it really has the unit sitting in a truly recessed crevice, so it might not be the best solution in looking for marginal aero gains. Besides, it's a hell lot more expensive than other mounts and very heavy for a stem.

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neeb
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by neeb

DMF wrote:Most likely answer, there is no definitive answer unless you wind test every single different scenario. And also, for the considerably largest part of your riding you are facing the wind at yaw angles. And those are for the better part larger yaw angles than you think due to the movement of the bike in relation to actual wind angle.
I was thinking along the same lines myself, although I do suspect there is a position that has a good chance of being near-optimal for the majority of set-ups. I guess the thing to do would be to look at the set-ups that the more "marginal gains" orientated pro teams adopt. I wouldn't put it past some of them to have tested this sort of thing in the wind tunnel.. :wink:
Calnago wrote:Seriously? As I sit here sipping a glass of wine, I almost spit it up. If you can tell a difference in aero between a Garmin mounted in line with the stem (looks the best and easy to read as you mentioned) and in its most aero position (straight ahead into the wind) then bully for you. I'm sure you'll get some more useful answers than this. But i don't think you'll notice a difference either way.
Well, I hope I wasn't responsible for the loss of any good wine - as it happens was sipping a nice Pinot Noir myself when I started the topic. :)

I agree that any gains are highly unlikely to be noticeable, but I think it's reasonable to assume they might be just as significant as a whole bunch of things that some people (or marketing departments at least) want us to take seriously, such as integrated front brakes or cable routing. Unlike those things however this is free and can be tweaked in 30 seconds. So why would you not want to do it if there was even a slight chance of an advantage?

What prompted this was reading a feature on the new version of the Boardman AiR aero road bike - Chris Boardman said that one of the most significant aero improvements in this version came from altering the cable routing at the front. The fitting instructions for Campagnolo ergo levers make a point of warning you to angle them precisely forwards for aero reasons. People pay good money for supposedly aero handlebars with aerofoil profiling on the top, etc...

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jekyll man
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by jekyll man

most aero position for it is........

left at home on the sideboard, or in your pocket
:roll:
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Philbar72
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by Philbar72

it won't make the slightest bit of difference. 85% is the rider, the rest is tiny from the frame and mostly the wheels. at speeds on the flat it won't make a jot of difference.

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legs 11
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by legs 11

:lol: :lol: :thumbup:
Best place is at home on the side and just bury yourself.
The extra disturbance to the air from looking down at it will far outweigh its position or angle. :up:
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neeb
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by neeb

Pardon me, next time I'll go to aero weenies.

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legs 11
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by legs 11

Nothing to pardon yourself about mate. Just trying to be realistic about the situation.
We always welcome comments about things in a sensible way around here, I suppose there are situations where it could be an issue......the hour record, Olympic track pursuit, maybe the world champs etc. I'd guess the minimal gains in question would have to mean competition at the absolute top end of the sport (even then it's arguable). What I meant was how much disruption to your aero profile does looking at your Garmin cause?
Seriously, I don't think it's an issue, just put it at a sensible angle and you'll be fine.
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DMF
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by DMF

Exchange the question for "Most favourable place to save 10 grams on the bike?" and the answers would be a lot more constructive, even though it makes even less of a difference than 10 degree angle change of the Garmin might...

But I digress, and in no way mean to open the Pandoras Box on aero vs weight. (...or, do I? hehehe)

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legs 11
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by legs 11

You see, we're a good bunch of people on the whole.
One of the reasons I've been here for such a long time is the decent, and sensible replies that (normally) accumulate.
The issue is.......looking at your Garmin isn't going to make you faster. Brute strength, power, aero form, technique, power to weight ratio, mental approach.......These are things that will make you faster, looking at your Garmin is unlikely to help that much.
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eric
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by eric

Level would be more aero. It's leading everything and no "turbulence from the front wheel" will reach it.
So there are no complications and the simple answer is correct.

But as noted, a very small difference.

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neeb
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by neeb

DMF wrote:Exchange the question for "Most favourable place to save 10 grams on the bike?" and the answers would be a lot more constructive, even though it makes even less of a difference than 10 degree angle change of the Garmin might...

That was sort of my point with the last comment.. :wink:

The standard anti-ww jibe of "just take a dump before you go for a ride" is at least as true as the idea that looking down will have more effect on aero properties than the angle of your computer (not that the latter isn't also true).

Of course all of those tiny things potentially add up to something (almost) significant - and unlike hidden brakes and internally routed cables, this one doesn't cost anything and is 100% controllable (unlike your bowel contents or the position of your nose :))

legs 11 wrote:The issue is.......looking at your Garmin isn't going to make you faster. Brute strength, power, aero form, technique, power to weight ratio, mental approach.......These are things that will make you faster, looking at your Garmin is unlikely to help that much.

Yes yes... In any case, clearly the cycling gods agree with you because just after starting this thread my Garmin 800 died (again).

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