Originally Posted by
steelbikeguy
The nice thing about helmet mirrors is that you should be normally looking forward, where most of the traffic issues are. With your helmet mirror set up properly, it will be showing you what is directly behind you. If this isn't the case, the mirror needs to be adjusted.
The other nice thing about a helmet mirror is that it is located roughly 3.5" from my eye, and the one I use is a little over 1" in diameter. Using basic trig, that tells me that it provides a 16 degree field of view. With a handlebar mirror located 36 inches away from your eye (and probably more), you would need a 5 inch diameter mirror to get the same field of view.
I've had friends that initially had difficulty with helmet mirrors, but with time, were able to adapt to them.
Steve in Peoria
Hi Steve!
I agree that you should have your attention focused in front of you. And for that matter, you should take as little attention away from what is in front of you for as little time as possible- the helmet mirror shows what is behind your helmet, and what is behind your helmet is dependent on what direction your helmet is facing. There's an incredible range of angles at which your head will be facing "forward" but only a small range that will put the mirror where you want it. You need to find the mirror, find where your field of view is, process that, adjust your helmet (head) and process the information and take action. Instead of glance down to where you know the mirror is, and where it's pointed.
Isn't what determines the field of view the convexity of the mirror? Any mathematical formula for distance to the mirror and size of the mirror depends on the convexity of the mirror to relay the field of view. (hence the 'objects in mirrors are closer than they appear' stickers on some mirrors) I've had 2 different mirrors- I think it was a Third Eye, that kind of stuck on to the helmet (and promptly fell off), and a "Take A Look" that clips on to a glasses arm or helmet visor... Both had similar fields of vision, but again, the same principle applies to the direction of your head.
I can understand someone not wanting a big ol mirror dangling off their bike- especially a 'racing' bike- it makes sense to find a different solution. And I totally understand how a user can reduce the effort in performing a complicated task sequence by familiarity.
In this case, I'm looking a reasonably sized mirror that doesn't interfere with braking or shifting. It seems the only option to get my preferred style and location of the mirror is to change back to non-aero levers. (which I might do *just* as a stylistic consideration) Out of the options that I'm seeing available- none mount to where I want them to mount, but that Selle Italia Eyelink that [MENTION=116365]chewybrian[/MENTION] linked to is really effing nifty... I do also like the Blackburn mirror that [MENTION=419195]rickrob[/MENTION] linked to.