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Upcoming Rally: Myrtle Beach,SC May 15-20 Cali Bakers Firehouse (Next to Hooters) North Kings Hwy (17) Map
Upcoming Rally: Myrtle Beach,SC May 15-20 Cali Bakers Firehouse (Next to Hooters) North Kings Hwy (17) Map |
Can Am BRP Spyder Installation
Windshields Plastics Windshields for motorcycles are made from either polycarbonate (Lexan) or acrylic (Plexiglas). Each type of plastic has advantages and disadvantages. Polycarbonate is an extremely strong plastic. Polycarbonate is about as transparent as glass. Polycarbonate cuts and forms easily at both room temperature and at higher temperatures. For machining purposes, you can work with polycarbonate pretty much the same as you would aluminum. Polycarbonate has a major drawback for windshield use: polycarbonate picks up water from the air. The water eventually makes the polycarbonate cloudy. This water will form bubbles if you heat the polycarbonate to forming temperatures. So, before you can form polycarbonate, first you have to place it in a drying oven at about 200° for about 12 hours. Because of this, only companies that manufacture polycarbonate make windshields. Polycarbonate is sensitive to ammonia, so glass cleaners like Windex should not be used on polycarbonate. Polycarbonate windshields need a coating to protect them from chemicals and prevent them from absorbing water from the air. This optical coating is difficult to apply uniformly, resulting in optical distortion. It also scratches and cannot be repaired with plastic polish. By far the most popular polycarbonate for motorcycle windshields is GE Lexan Margard MR10, aka "quantum coated." GE polymers was recently bought by a Saudi Arabian firm, Sabic - see GEPlastics.com. We don't buy products from countries that fund terrorism.Acrylic is only about 3% as impact resistant as polycarbonate. Normal acrylic shatters upon impact, and therefore is considered an unsafe material for windshields. Acrylic is very chemically resistant, and is more transparent than glass - glass absorbs about half again as much light as acrylic does. Acrylic forms easily at high temperatures, about 300°. However, machining acrylic at room temperature is difficult. It's not very easy to cut acrylic with a saw or drill holes in acrylic without shattering or weakening the material. Polycarbonate is a DOT approved material for making windshields; normal acrylic is not. Some states require DOT approved windshields, and therefore in these states a normal acrylic windshield is actually illegal, however these laws are rarely enforced. Normal acrylic can be shattered by an impact from a rock moving at speeds as low as 15mph. A special high cost acrylic called Impact Modified Acrylic is available. This form of acrylic is DOT approved for windshields. We use only DOT certified impact resistant plastics to make Calsci windshields. Our windshields will not shatter if hit by a rock. We test our windshields by shooting them with a .22 caliber rifle and verifying that the windshield maintains its basic integrity without shedding small pieces that could impact your face or eyes. No windshield can protect you against everything, but we do our best to make certain that our windshields protect you against the small rocks frequently thrown up by other vehicle's tires. Optics Even though Calsci windshields are designed so that you look over them, not through them, we use only optically correct shapes that will not distort your vision if you do look through the shield. If you look through one of our shields at a dividing line on the highway, you'll see essentially no bending of the straight line. You'll never get a headache from looking through one of our shields. Aerodynamics Nearly all of our windshields have vents. These vents are part of the aerodynamic design of the shield, to reduce turbulence and noise. They are not there to make a flow of air on the rider. When you're riding on the highway, any windshield is pushing air away from the rider. This leaves a low- pressure pocket between the windshield and the rider. The air flowing past the motorcycle wants to drop into this low pressure area. If the outside air is allowed to spill into the area between the windshield and the rider, the result is turbulence, noise, and drafts. When outside air spills into the rider area, it almost always falls in a curved path, causing spinning vortices of air. These vortices are noisy and can cause the battering and hammering on your helmet reported by some riders. Our windshields and vents are designed to funnel air into the rider region to relieve this low pressure area and greatly reduce the tendency of outside air to spill in. The vents are designed so that the air coming through them is quickly dispersed, leaving almost no detectable air flow at the rider. Our goal is to produce almost completely still air on the rider with no back pressure.I get a lot of emails, "Can you make me a windshield with a reverse flip to kick the air up over my head?" Yes, I can, but I won't. Air is a spring - there are shock absorbers made with only air as the spring. When you kick a spring, it kicks back. Putting energy into the air like this is exactly the opposite of what we're all about. Windshields with reverse flips and non-fair shapes generate semi-periodic chaotic swirls of turbulent air, called Von Karman vortices, after Theodore Von Karman. These vortices, or pockets of turbulence, grow as they move away from your windshield. If you feel your head being rocked or even slammed side to side or front to back as you ride, this is Von Karman vortices at work. Some manufacturers, to my own astonishment, actually claim to produce these vortices on purpose, apparently with the idea that some turbulence is "good" and will somehow perhaps cancel out the "bad turbulence." We work very hard with the design of the shape of our windshields and the location and size of the vents to eliminate all Von Karman vortices.
Theodore Von Karman emigrated from his native Hungary to the US in 1930 to become the director of the aerodynamics laboratory at Caltech. Mark learned his aerodynamics in Von Karman labs at Caltech. Calsci windshields are designed using aerodynamic engineering principles that guarantee our shields do not generate turbulence. These are the same shapes that minimize drag and maximize fuel mileage. If you love math, give us a call and we'll tell you all the gory details. Hint: our shapes are all solutions to Laplace's equation, ∇²φ = 0, which guarantees a fair shape, that is a continuous second derivative. Design All our shields are laid out on a computer and cut with an industrial cutting laser. Our shields are symmetric to within a thousandth of an inch (.025mm). All mounting holes are also drilled with the laser, guarantying an excellent fit to your bike. This precision is necessary to be certain your riding experience will be precisely the same as all our other customers, and precisely what we engineered for your bike. Our windshields are designed by Mark Lawrence and Carl Porter. Carl has a Bachelor's degree and a Master's degree in engineering from Ohio State University. Mark has a Bachelor's degree in engineering from the California Institute of Technology, and is currently working on a PhD in physics at the University of Southern California. Carl and Mark don't agree very well about college football teams. Mark has a bit more than 550,000 miles of motorcycle experience. It takes about 6 weeks, eight to twelve prototypes, and typically several thousand miles to finalize a windshield design. Our windshields are not just a stock windshield made a bit wider and taller. We build and modify our prototypes until the resulting windshield is quiet, comfortable, and attractive. How to choose the best windshield height for you. The yardstick method below gives the correct answer, including adjustments for your riding posture, handlebar height, seat height, etc. The table below is only approximate. To use the table, get a size estimate from the table using your height and pants leg length. If you're between sizes, use the larger size if you live in a colder climate, or the smaller size if you live in a warmer climate. People in Florida or Houston need somewhat shorter windshields, people in Seattle or Juneau need taller windshields. Both the yardstick method and the table are for people who want to look over the windshield. If you want to look through the windshield, add about 3" to your windshield height. Of course the quietest possible ride is when you're looking through the windshield, but only about 1% of our customers are interested in looking through a windshield. Younger guys (under 35) typically want about an inch or two shorter windshield to get a sportier feel. Older guys (over 45) typically want a more quiet and comfortable ride and prefer about an inch taller shield. If you want coverage for your body up to your shoulders, but your head in undisturbed full-speed air, then your windshield's top edge should visually hit the ground about 10' - 12' (3 - 4 meters) in front of the front tire contact patch.
If you buy a windshield from us, you can wrap it in plastic wrap a couple layers thick, then cut the plastic wrap away from the vent, then mount it. The plastic wrap will protect it from bugs, scratches when mounting, etc. If you might send the shield back for an exchange, please don't scratch it first. And, trust me, as impressive as your state's bugs are, I already have as many bugs as I need. Ride the windshield for 15 minutes or so. If you bought the wrong size, we'll trade you. Or, put some masking tape on your shield where you would like it cut, and we'll cut it to your spec. We want happy customers.
We make our own cleaning fluid. When you buy a windshield from us, we give you a small spray bottle of cleaning fluid and a micro-fiber cleaning towel. Here's our "secret" washing fluid recipe, the result of testing about 25 different formulas: Makes 1 quart = 1 liter windshield washing fluid
We recommend using only micro-fiber cleaning towels on your windshield. If you don't want to play home chemist, go to WalMart and buy a gallon of Peak Windshield Cleaner (blue), about $1, and a gallon of Peak Bug Remover / RainX (green), about $1.50. Mix them 50-50 and use that on your motorcycle and in your car.
Scratches in our windshields can be easily repaired with any good plastic polish. McGuire's, Plexus and Novus are three good brands. You can buy a 3 bottle kit of Novus #1, #2, and #3 on Ebay for about $10. We use #1 in house to clean and polish our windshields, and #3 to repair any small scratches that happen during the manufacturing. #2 is used to remove any tiny scratches left by the #3 process. To repair a scratch, use a good cloth - a used diaper, or the microfiber cloth we supply is good. Rub across the scratch with #3 until the scratch is visually gone. Then rub against the #3 direction with #2 to clean up the area. Finally, use #1 to polish the windshield.
You may paint your Calsci shield with pretty much anything. Paint from the rear of the shield, and preferentially use Acrylic Enamel paint. From the front of the shield it will look fantastic. To drill a hole in your windshield, it's best to use a slower speed drill, like a battery powered drill. Also it's best to use acrylic bits, available from Craftics.com. You can do this with normal tools if you're very careful. Drill a small pilot hole in the center, 1/8" or 3/16" (3-4mm). With the full size bit, drill from the front of the shield just enough to make the full diameter hole on the front, but not all the way through. Now turn the shield over, support it on a piece of wood, and drill from the rear all the way through. Drilling from both sides like this minimizes the chances of chipping the shield as your bit completes the cut. To cut away part of your shield, first cover most of the front of the shield with masking tape. You don't want to scratch your shield. Mark on the tape with a black felt tip pen where you want to cut. Cut the shield with a band saw, saber saw, or dremel tool using a blade with 12 to 14 teeth per inch. Cut triangular pieces off the corners in preparation for rounding them. Or you can use the top piece you cut off to mark corner curves on your new top edge. You can remove smaller sections of plastic using a sanding drum attachment on a dremel tool. Mark the shield first with a black felt tip pen and cut to your mark. You can draw directly on the plastic, then later wash off the ink with alcohol.
When making custom cuts, we use a band saw with a 12 tooth per inch non-ferrous metal blade; a floor mounted belt sander with 80 grit sandpaper; and a plastic scraping tool from Craftics, available on Ebay, Amazon, DelviesPlastics.com, ProfessionalPlastics.com or Craftics.com. |
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Sand
new rounded corners and straighten your cut edge using a floor mounted belt
sander with 80 to 120 grit sandpaper. If you don't have a floor mounted belt
sander, you can get similar results by securing a hand held sander upside down
in a vise and holding the windshield over that. Use a sharp piece of metal, like
an open scissors, to scrape the sanded edge. This will give you the same edge as
sanding with about 600 grit. Scrape with the scissors to break the sharp corners
on the edge.
