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Color me Gone
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Discussion Starter #1
I have only tried it about ten miles now but early seat of the pants and noise test are good. It's hard to tell your not running topless by the throttle and the induction noise is much less. Looks more like swiss cheese. :)

 

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Color me Gone
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Discussion Starter #3
John there is some induction noise but it is much less then running topless. It does not let it echo right out the side it muffles it in the top of the air cover.

Max
 

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Color me Gone
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Discussion Starter #4
I did this to my old 02 cover if I were to do it over again I think I would try just the four holes in the front and not the holes in the rear.
 

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I was thinking of doing something similar but ONLY around the parameter where the a/f actually would pull air from.


John
 

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Color me Gone
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Discussion Starter #6
John I wanted to keep the holes away from the sides, I wanted greater airflow without being able to hear the valves when I opened the throttle up. By the amount of induction noise I still get I can tell it has no restrictions like this.

Max
 

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Max said:
I did this to my old 02 cover if I were to do it over again I think I would try just the four holes in the front and not the holes in the rear.
Max,
You may want to consider covering the back holes with some duct tape and see if that eliminates some of the noise.


John
 

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Color me Gone
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Discussion Starter #8
John it is not nearly as loud as it is when you run topless. I was also concerned about water and hydrostatic lockup. I have been caught in some real terd floaters and could see if the gap was wide open at the side when the top is off that some if not a lot of water would have run through the engine. With car engines we deal with this problem all the time and when they drive through a puddle fast it can destroy an engine.

Max
 

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Max: Been there, done that with a 944 Porsche. The rebuild cost on the 944 motor ($13500) exceeded its value (= totaled & I was very upside down). I drove through about 4" of water. The air intake is in the left front fender. If you hit the water just right.......
 

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Live Free or Die
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I would think that you would want to equal, or slightly exceed the "cross sectonal area" of the two throttles, to create the pressure of one atmosphere around the filter (I also assume that in the stock configuration, the air box is under negative pressure). So the holes cut into the cover would only need to have the equivalent area of the throttles minus the area of the existing snorkel tube.

I suppose another factor that needs to be taken into account is the height of the gap between the perforated air box cover and the V-Rod top skin. This gap would also influence the restrictiveness of the air flow into your Swiss cheese holes. If the gap is tight, more perforated holes would be needed...
 

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Color me Gone
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Discussion Starter #11
Via VRSCA, having used plastigauge for years on crank and rod journals I wanted to find out how much room was underneath the cover. Using play-doh on top of the lid and installing the cover it measures just over 1/2 inch thick. So my guess is that I am not restricting any air at all and the holes are probably more then the amount required. The holes are all cut with a 2 1/8 inch hole saw so they are probably about 6 times the volume of the the throttle bodys.

As I stated earlier after making this cover I think that four holes near the front might be the best configuration. That is also the area that has the greatest distance to the air box cover.
 

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SNAFU
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I think John's mod, taking away most of the front, vertical section, is the best I've seen. One thing it "might" also do is pack a little air aka Ram Air where topless and Max's mods probably allow all the air it will take, i.e. no negative pressure.

Just my thoughts, I'm lazy, I run topless and love the sound ;)
 

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mjw930 said:
I think John's mod, taking away most of the front, vertical section, is the best I've seen. One thing it "might" also do is pack a little air aka Ram Air where topless and Max's mods probably allow all the air it will take, i.e. no negative pressure.

Just my thoughts, I'm lazy, I run topless and love the sound ;)
For those who didn't see my CRUDE mod Mark was referring to, here it is.



I took off about 2 inches off the snout and smoothed the edges first and then cut the ugly holes.



John
 

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John,

When you did your tune and dyno run were you topless or did you have your modified lid on. Also was your dyno done with oxygenated fuel. If so what is oxygenated fuel.
 

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Frank,
I didn't. I knew this how I wanted to ride the bike. I knew I didn't like the way it sounded topless, so I used my knowledge of the effect of hood scoops on my race cars and street rods. I knew that they made more power with a scoop that wide open. Having said that, I'm not convinced my set up makes MORE power than topless because there is a lot of crap in front of the intake. But I also feel VERY confident that I'm making AT LEAST as much power as running topless. Sorry I couldn't give you a definitive answer.

John
 

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Frank,
Another thought. There is NO way my set up would make MORE power that topless on a stationary dyno! It MIGHT make more power with the potential ram air effect at speed but NO way on a dyno. Think about it.

John
 

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You are absolutely correct. So maybe we are making more hp at speed than we are on a stationary dyno. I am sick for more hp and power! Never satisfied:diablo:
 
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