Ram air?

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trevor42
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Ram air?

#1

Post by trevor42 »

Greg Foresi's latest endeavor http://ngwclub.com/forum/viewtopic.php?f=47&t=43563 got me to thinking (which is usually where the trouble starts). Has anybody ever experimented with ram air on a 'Wing?
I know some manufacturers-Kawasaki comes to mind-have successfully implemented ram air into their bikes.
What problems could be encountered by forcing more air into the carbs as road speed increases?
"No battle plan survives contact with the enemy." - Prussian field marshall Helmuth Karl Bernhard Graf von Moltke

1979 GL1000 - rebuild in (slow) progress
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robin1731
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Re: Ram air?

#2

Post by robin1731 »

trevor42 wrote:Greg Foresi's latest endeavor http://ngwclub.com/forum/viewtopic.php?f=47&t=43563 got me to thinking (which is usually where the trouble starts). Has anybody ever experimented with ram air on a 'Wing?
I know some manufacturers-Kawasaki comes to mind-have successfully implemented ram air into their bikes.
What problems could be encountered by forcing more air into the carbs as road speed increases?

It's possible. But tuning ram air with CV Carbs is the tough part. It has been mentioned many times. CV carbs do not like moving away from the stock air box. It takes time and a lot of patience to get the jetting right if you do.

Cyborg has a sort of ram air tube in his bike. But it is one small tube feeding the stock air box (I believe). So it isn't that much different. He seems very happy with that.
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CYBORG
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Re: Ram air?

#3

Post by CYBORG »

my system uses a tube about the same size as the intake nozzle on the air cleaner. the air box is sealed to hold pressure, and draws its air from the front of the fairing. at speed, rather then the air being drawn in, it is forced in. at 75mph the internal pressure of the air box is only about 2lbs. however the air is cooler then the air it would normally get from off the coils in the stock configuration. also a slight amount of pressure causes a little more air to enter the cyl. then is normally drawn in by cyl vacuum. this does cause a slightly lean mixture at speed, which can be cured by raising the needle. performance increases are really not that noticeable. the main one being that the engine likes the cooler air better
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fish
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Re: Ram air?

#4

Post by fish »

ram air is a marketing ploy & a gimmick
Any ram or scoop big enough to make an appreciable difference is going to cause aerodynamic drag that equals the amount of HP increase.
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Hal
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Re: Ram air?

#5

Post by Hal »

I'd say it's more worth doing from the point of view of letting the engine breath cold air rather than hot.

I have two larger tubes feeding the airbox, both running to holes in the front of the faux tank sides. The air around the coils, above the engine, must get quite hot, and the mouth of the spout IS very close to the coils.

Twin intake airbox...

Image

Insect eye intake hole....it has a matching duct behind it. Negligible ram effect though.

Image
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so....probably best use Tipp-Ex in future?"

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fish
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Re: Ram air?

#6

Post by fish »

You have a good point Hal.
Here in Arizona my NGW does not mind the heat & runs fine no matter how hot it is.
My air cooled Volkswagon gets pre-ignition when it is 50c.
my cylinder head temp gauge and oil temp gauge are in range so I know it is not overhearing.
soooo.. I see the benefits of lower intake air temps.
Timothy Mark Fisher
Catalina Arizona
"ride it.. don't be one of those guys who will fix it 'til it's broken" (JDVorchek)
"It is not logic or economics that drive a motorcyclist but passion!" (bugdaddy66)
"I fully agree with fish, well at least 27% of the time."(Casper)
"Why do you have to ruin a perfectly good thread with common sense"(Placerville)
"my best guess for an answer would be a stream of complex expletives" (Transitman)
"I like a cold beer with my beer" (OldeWing)
"Most of us like the sport of wrenching too." (fred camper)
"Now go ride the heck out of it, til mother says do your chores"(Gowing)
"I agree with Fish" (Salukispeed)
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Re: Ram air?

#7

Post by egelasi »

First thing I thought of when I saw that dual intake
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Re: Ram air?

#8

Post by SloMo228 »

egelasi wrote:First thing I thought of when I saw that dual intake
:lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol: :lol:
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Re: Ram air?

#9

Post by gregh35 »

I think the small amount of overpressure that could be gained from running at speed is only worth the tuning effort to a racer, not so much worth the effort to a streetbike. The cold air benefits are worth the effort though in my opinion. Colder, denser air is worth it to me to a point.
I've these BMW fairing vents I'm going to mate to my Vetter sooner or later:
BMW RT fairing vent 1.jpg
BMW RT fairing vent 2.jpg
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Re: Ram air?

#10

Post by gregh35 »

I like that dual inlet airfilter box up there Hal. Looks like you've done a nice job on it.
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Re: Ram air?

#11

Post by CYBORG »

like i stated, i think the cold air advantage is a good one
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trevor42
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Re: Ram air?

#12

Post by trevor42 »

Hal,
That intake and airbox are very nicely done!
The cooler intake air temps are something I hadn't considered. Colder air, being denser, could certainly provide some benefits.
"No battle plan survives contact with the enemy." - Prussian field marshall Helmuth Karl Bernhard Graf von Moltke

1979 GL1000 - rebuild in (slow) progress
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