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I have been very nearsighted since around the third grade. I was the kid in class who had those heavy plastic, dark-rimmed glasses with thick-edged lenses.
But, I could see those real slate blackboards clearly after getting them. Modern versions and variations of those old frames have served me well for more than five decades now.
Those old-style frames have come back into style, but they may not be the best way to see what's going on when riding a motorcycle.
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| Not me. |
Lets look at the pros and cons.
Glasses
- They are quick and easy to put on. It just takes a second.
- They are easy to clean.
- Glasses do not promote eye problems like contacts might.
- Glasses lenses can be shaped to correct for astigmatism.
- For those suffering from presbyopia (literally "to see as old men"), the lens in the eye becomes stiff and cannot any longer focus on close objects. Thus two different powers of lenses are required to be able to see at a distance as well as close up. Such lenses are referred to as bifocals. Bifocal lenses are readily available, so you can focus on the road ahead
though the main part of the lens or focus on closer objects such as the
instruments, your GPS, or a map by looking through the bifocal near the bottom of the lens.
I have used progressive bifocals that do not have a line between the main and close up sections for many years, and find the vision adequate both far and near.
Nevertheless, there are alternatives. See
the references to types of bifocals for motorcycle riding below.
- Of course, the glasses must fit inside your helmet. This is sometimes a problem for large glasses and/or a tight-fitting helmet. When you buy a helmet, take your glasses and any liner you use to keep warm along to see how well they fit inside. When you buy glasses, take your helmet and the liner along to see about the same thing.
- Glasses can fog up, especially in cold weather. One way of avoiding this is to use a helmet insert like the Foggy Respro.
- Now, a subtle, but important issue with glasses:
Even a correctly fitted helmet moves a bit relative to the eyes. In fact, your scalp can move around on your skull even if the helmet does not slide on the scalp. Usually, the glasses are, at least in part, positioned by the helmet. So, when the helmet moves, so do the glasses.
Therein is the problem. The shift of the glasses moves the image your eye sees. When you go over a bump or the helmet is otherwise shifted, the image you see also shifts.
I have found this to be a significant problem when attempting sports where head movement is rapid. I believe that because I have worn glasses for many years that move slightly when my head moves, I have had trouble with hand-to-eye coordination. That causes me to be very poor at these sports.
If only I had been fitted with glasses that wrap and had a secure back strap so that they did not move around in front of my eyes, I might have been better at sports.
I find the same problem with motorcycling. The slight movement of the helmet/glasses on my head changes the position of the image I see.
I have not found any glasses that do not have this problem, and of course, a strap behind the head can't work with a helmet because you put the helmet on before the glasses. (You do wear a helmet, right?)
- Also, since the refraction in your glasses lens changes from center to edge, where you are looking through the lens changes the effective correction. That is, by the way, another good reason to turn your entire head to look where you want to go, rather than moving only your eyes.
Contact lenses do not have this problem. They move with the eye, and the resulting image shifts very little, even with violent head or eye movement.
Experience for yourself how the image moves when your glasses are moved relative to your eyes:
Put on a pair of glasses. Look though the normal part of the lens (not looking over the top like the guy below).
Move the glasses, first up, then down. Like this:
See how the image moves?
Now, instead of moving them up and down, move one side down and the other side up at the same time.
That is what can happen when you wear glasses when riding. Almost makes you dizzy, doesn't it?
The same thing happens side to side.
Not good.
Contact Lenses
There are two major types of contact lenses, so we will lump some of the pros and cons for both together first.
- They take some time to put in, take out
- They must be kept scrupulously clean. Cleanliness is vital to avoid eye infection and disease.
- They may cause the eyes to be dry and irritated.
- They don't fog up.
- They move with the eye, so the image is always in good focus no matter whether you are looking straight ahead or out of the corner of your eyes.
- If you need bifocals, you most commonly must use reading glasses with the contact lenses for up-close vision.
Gas-permeable hard lenses
- These are made of fairly rigid plastic that breathes.
- They provide excellent vision and correct for astigmatism by spanning the irregularities of the cornea that cause astigmatism with a film of tears under the lens. In effect, they replace the cornea as the refracting surface of the eye. I found this type of lens to be very good except for the fact that they made my eyes very red after wearing them for several hours. Surprisingly, they did not cause pain.
Because of the redness, I did not stay with rigid lenses.
- These are more rugged and longer lasting.
Soft lenses
- These are very comfortable for up to ten hours at a time on the bike.
- They provide very good distance vision.
- These lenses can correct for astigmatism by having the appropriate spherical lens contour to correct for distance and a superimposed cylindrical contour to correct for astigmatism. There is an orientation feature so the lens rotates to the correct position on the eye and stays there. These lenses are referred to as toric.
- I find that I can see my analog instruments clearly without having close
vision correction. The GPS, positioned a bit closer to my eyes, is
slightly out of focus, but using its audio directions in an earpiece helps to compensates for that.
- My eyes do not get significantly dry when wearing them.
- They more easily absorb pollutants than gas-permeable lenses.
This is the soft lens I wear:
What if you want to use contact lenses, must have bifocals to correct close vision, but don't want to use reading glasses? There are so-called bifocal soft contact lenses. However, I think it is
better for motorcycle riding to have lenses fitted for good distance
vision only.
Another method of providing close vision is to have one lens
for distance vision and the other for close vision. I think that is risky for
motorcycling, since good binocular visual acuity for distance vision is vital.
Read about these options and others with greater detail
here.
References to Types of Bifocals for Motorcycle Riding
What do you find best for riding?
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