New Velocity stacks

By the way, to Claviger, if what you are doing does not work, you are more than welcome to use my Carpenter intake as a plug for your form if you pay shipping and return it to me undamaged. I can send you pictures of it mounted if you wish.
@Claviger Rob. Get that copied and you'll be making a living fast.
Another advantage of the plenum is it pulls cool air in instead of the hot coming off the rad and over the engine.Rick
Yup even the OZ-claw suffers.
 
I have no interest in copying another's inherently flawed design. The intake setup they use, I'm sure, does well at speed as a ramair device, but it's in no way functional for a street bike. I consider use of a filter non-optional on the street.

Another way the use a plenum helps is this:
Using a foam filter, like a PX500 or PX600, allows the air to enter straight, it doesn't turn like when using a paper or cotton based filter to flow through the media. Initially it seems like an advantage, however, because of the orientation of the R3 TBs, air flows straight into the front of the filter, across the tops of the TBs, and onward out the back. What do we know about air flowing across an open face perpendicular to the desired direction of flow?

We know it's the opposite of good, its terrible. I recently watched a 2 hours tuning session with a turbo V-8 motor using a blow through carb setup, they fought it for 1 hour 40 minutes where it would inexplicably swing super lean as boost started to come on. They trouble shot everything, firing order, ignition timing, boost pressure, swapped carbs, tried a different distributor, etc etc until they realized the hat they were using to blow through was causing the air to do exactly that, flow across the venturi instead of smoothly through the venturi. It ran great without the turbo, made good power with the hat disconnected and allowed to breathe naturally aspirated. Engine ran like pure ass until they swapped hats for one that turned the flow 90 degrees to blow directly through the carb, after they identified that, and corrected it, the motor made phenomenal power.
 
I have no interest in copying another's inherently flawed design. The intake setup they use, I'm sure, does well at speed as a ramair device, but it's in no way functional for a street bike. I consider use of a filter non-optional on the street.

Another way the use a plenum helps is this:
Using a foam filter, like a PX500 or PX600, allows the air to enter straight, it doesn't turn like when using a paper or cotton based filter to flow through the media. Initially it seems like an advantage, however, because of the orientation of the R3 TBs, air flows straight into the front of the filter, across the tops of the TBs, and onward out the back. What do we know about air flowing across an open face perpendicular to the desired direction of flow?

We know it's the opposite of good, its terrible. I recently watched a 2 hours tuning session with a turbo V-8 motor using a blow through carb setup, they fought it for 1 hour 40 minutes where it would inexplicably swing super lean as boost started to come on. They trouble shot everything, firing order, ignition timing, boost pressure, swapped carbs, tried a different distributor, etc etc until they realized the hat they were using to blow through was causing the air to do exactly that, flow across the venturi instead of smoothly through the venturi. It ran great without the turbo, made good power with the hat disconnected and allowed to breathe naturally aspirated. Engine ran like pure ass until they swapped hats for one that turned the flow 90 degrees to blow directly through the carb, after they identified that, and corrected it, the motor made phenomenal power.

Who’s specifically flawed design...ozclaw?
 
Internal baffles can help with re-directing air flow and help manage acoustic energy. The high pressure area on the R3 is below the headlights, and above the radiator, like most other cycles. A plenum inlet tangent to the fuel tank and facing straight forward is out in the slip stream and therefore, is not in the best possible place and has less than an ideal orientation.

IMHO, neither the Ozclaw nor Carpenter inlet plenums are optimized for performance. However, they look kind of nice.
 
The entry to the plenum is more important than you might think. Too big and the plenum becomes "open." Too small and it becomes restrictive, though the larger the plenum the smaller the inlet can be made. Don't get hung up on tuning to a resonance. Use reversion from valve closing events to your advantage by reflecting them into opening ones. This gives you several characteristics to use: volume, distance to reflective surfaces, and shapes. You have created one variable reflection based on the length and geometry of your v-stacks. Now think about the opposite of a v-stack on an opposing wall. (Think parabola.)

You can use simple microphones and a recorder to capture lots of data in various places in the plenum once you have the thing installed. Look at it with vibration analysis software to clarify how it is working and then tune from there.

When I re-read the above I thought of the trumpet mute as below.

Is this the 3D Parabolic cone shape you where inferring should be on the opposite plenum wall to each intake trumpet?
If so should it be a similar scale to the intake or a much lower profile version?
In ether case how would you determine the width apart to benifit from any 'wave' which would also refine plenum shape and volume requirements?



upload_2019-7-20_16-23-43.jpeg
upload_2019-7-20_16-24-23.jpeg
 
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