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Discussion Starter · #1 ·
Hey, ya'all...

Once John (my BF/crew chief) knocked the screens out of his lowered '99 Busa, his bike became much less susceptible to radar. (by removing the screens, he effectively eliminated any flat surfaces for radar to bounce off of, and it's lowered 3+ inches front and rear - most radar guns are mounted higher than the body of the bike). He's now considering adding the induction "scoops" but was wondering how that will impact his "stealth-ability".

Anybody have any insight???
 

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Perhaps you should post this in the Lockheed-Martin forum.:D
 

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Wait'll they get a load a me...
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I think bikes are a little harder for radar to pick up anyway. We have one of those speedlimit signs here that tell you how fast your going & it wouldnt pick me up when I wheelied past it one afternoon. Also, we were out drag racing 1 night & a friend of ours who is a cop came out in the patrol car & went to the finish line to see how fast we were going. Radar wouldnt pick bikes up.
:confused
 

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Discussion Starter · #5 ·
And I was startin' to think that only the slowpokes had made it here from SBN! :rolleyes Thanks, Bishop.

So does anybody have any experience with the inserts?
 

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I don't understand how a radar gun can pick up a baseball when pitched at a game, but not a bike. They are the same type of radar right?:confused


Dustyn
 

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KBOlsen, if it's insight you want, then it's insight you'll get...

I got your FRIED NOODLE right here! :redflip

RADAR stands for Radio Detection and Ranging. Most police radars are not capable of determining range, this is mostly used in military applications. The energy from RADAR will travel indefinitely unless it is either reflected, refracted or absorbed. Radio energy always travels at approximately 186,000 miles per second. Depending on the size, shape, speed, composition and exact location of an object, it's reflected signal may not be "seen" by the RADAR unit. Police RADARS use another characteristic of radio energy in order to measure speed. That characteristic is that the frequency (cycles per second) of a radio signal changes when the signal is reflected back from a target that is moving at a different speed that the Radar set. This change or shift in frequency is known as the "Doppler" shift. If there is relative motion between the RADAR and the target, there is a shift between the transmitted frequency and the frequency of the small signal received back from the target. This frequency shift is determined by the police RADAR by comparing the returning signal frequency with the transmitted shift. By measuring the degree of frequency shift, the RADAR is able to display the target vehicle speed in miles per hour. In radio signals, wave length and frequency are closely related. Both radio and light travel at approximately 186,000 miles per second. Therefore, any given radio wave length is associated with a specific frequency. For example: X-band = 10.525 gigahertz, K-band = 24.150 gigahertz, Ka-band = 34.700 gigahertz. In each case, the frequency times the wave length ALWAYS equals about 30 billion centimeters per second, which is the speed of light. Remember, the frequency change only happens when there is RELATIVE MOTION between the RADAR and the solid object. Also of importance to us, the motorcylist, it is a fact that when a motorcycle, car, truck's direction makes an angle with the position of a stationary RADAR, the relative speed will ALWAYS be less than the true speed, and since the change in the signal's frequency is based on the relative speed, the RADAR speed measurement will be lower than the vehicle's true speed. This is known as the angular effect (sometimes called the cosine effect). This effect will always work to the motorist's advantage when the RADAR is operated in the stationary mode. The shape of a vehicle will be a big factor in how much energy is reflected back to the RADAR. A RADAR beam will bounce off a surface at the same angle at which it striked the surface. If the surface is slanted, some of the reflected energy will head off into space and not be picked up by the RADAR receiver. Many times, if a smaller vehicle is traveling next to or in close proximity of a larger vehicle, such as a tractor trailer or truck, the smaller vehicle's relected energy may be overshadowed by the larger vehicle's. There are many more factors which determine a RADAR's effectiveness. Interference such as man made objects can hamper a RADAR's accuracy. Moving objects, such as rotation signs alongside the road will reflect the RADAR beam and cause Doppler shifts that are interpreted by the RADAR receiver as vehicles. The patrol vehicle's own defroster fan can sometimes create interference when the RADAR beam is transmitted through the front windshield. Fluorescent lamps, neon signs and similar devices are also examples of objects that can create the false signals.

Bishop, there are many factors which may have reduced the RADAR unit's effectivness the day your friend "clocked" you on your bike.

Hope this helped....:redflip
 

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I remember seeing a response from a law enforcer in another thread a long time ago, in a galaxy far, far away... Oh, anyway he made the comment that it is even harder to pick up a bike if the high beams are on. I don't know why, and I don't know if it's true. As far as the baseball radar goes, good question. My guess is it has something to do with the freqeuncy of the gun and/ or the material composition of the target.
 

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Well I can tell you I've been pulled over by a very upset cop who couldn;t radar my Busa. He alleges I was going at least 2x the speed limit but couldn't get his radar to give him a speed reading. MAn was he pissed off. So yes Busas are hard to radar. And this cop was coming right at me and there were no onstructions at all. We were separated by a 15 foot wide flat, grass median with no trees. Wound up getting my bike towed b/c I let my license expire and the cop just had to get me on something, right?

by the way my Busa front end is stock height and I have teh grill inserts. They catch a lot of bugs so I would never remove them.
 

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Sentinel... Good stuff man. Good to see a fellow biker geek.

Baseball question:
Cops want to avoid false positives. What if there is a diving hawk in the background, how do you know that the speed the gun returns is the car and not the bird? The larger and more radar reflective an object is, the stronger it's reflected signal will be. Most traffic radar guns have a built in filter that ignores any signal below a certain strength so you don't get speed readings from diving birds and thrown baseballs. Baseball radar guns have no need to filter the signal, they know that there is nothing else in the background moving that fast.

Being lower than the radar gun is not a big help, think of the radar beam like a flashlight, not a laser. If you are 6 inches below the axis of a flashlight you still get illuminated, albeit not as strongly.

Removing the screens probably helped reduce the signature, it also increases your chances of sucking large pieces of crap into your airbox. I'd be checking my airbox regularly if I were your buddy.

Now I wonder if naked bikes with their more varied angles and surfaces are easier or harder to radar than faired bikes? Look at the stealth fighters, its varied angles that scatter the signal and reduce the signature.

David
 

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Discussion Starter · #12 ·
Thanks, guys!

Sentinel... all that and ya ride a Tiller, too - HOT damn!
:bigcool

Think I'll get him the scoops for his birthday... see if they make a difference.

Oh, and the bike has 25,000 miles on it without the screens... and the bike still runs pretty near flawlessly.
 

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You're so big you HAVE to ride a Busa, huh?
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For what it's worth I read an article about these Nose scoops for the Busas. I can't find the link right now but basically it said they didn't add any value and under certain conditions were a detriment to airflow into the airbox.

Sorry i don't have the details the I can tell you that I was put off enough to NOT get the scoops. If you want to get somethinghtt is supposed to work try the Aluminum (or plastic) airbox/frame/inlet connectors forhte Busa. They have been reported to seal MUCH better than the stock ones.
 
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