Front derailleur cover?

Has anyone seen of or made a front derailleur cover for a standard Ultegra/Dura-Ace frame-attachment? It’s certainly down the list of things to pay attention to after; frames and hydration and wheels and position and clothing etc, but it seems silly to leave what might be a watt just hanging out in the air.

If nobody has manufactured one, I might tinker around and build one myself. Suggestions?

I’m aware that RALtech built a RD cog housing which solves part of that problem, but the more dynamic nature of that piece of equipment seems to preclude a neat solution for it.

Are you suggesting an aero chainguard for use with a 1x drivetrain?

…because that’s not a bad idea.

I wasn’t - I was thinking merely about something round with a tail to cover the ugly frame attachment on my 2x FD - since hills are a feature of most NZ triathlons there’s little point running 1x.

But your suggestion is a very good one for any flat courses.

I don’t think it would be legal. At that point, you are adding a fairing to a part of the bike. So it probably has not been done because of: very small potential gain, possibility of getting a DQ if/when noticed.

Fair enough. It seems silly to throw speed away, however. I’m guessing that a functional device would be more than legal, in the way that TriRig’s brakes are.

Perhaps construct it in a way that it would fall under the guise of a chain catcher? If it was for Di2, I sort of envision it as encompassing most of the upper section of the FD and basically being a small fairing since the top doesn’t, unlike mechanical.

I can remember reading somewhere here that the Front Der. accounts for minimal to zero drag in the wind tunnel. Meaning, a removed FD on a bike running 1X10/11 showed no difference in Aero compared to one that was there as usual.

That’s one thing I’d like to see tested. Depending on the frame, bottles, and wheels the air that area might be quite dirty or somewhat clean.

And just cause you can’t measure it doesn’t mean it’s not there. Or worth spending $100 on.

http://www.tririg.com/articles.php?id=2014_09_Cervelo_New_P2_Review&page=3

“This bolt-on mount adds a few grams of weight compared to a riveted mount, but as you’ve shown, lets you neatly run a single ring and leave off the derailleur and mount. FYI: that FD mount alone has more drag than the whole down tube.
Damon Rinard, Cervelo Senior Technologist”