the power now



57 replies to this topic
  • yz426quad

Posted April 29, 2002 - 04:54 PM

#21

Hello,does any one know what month DirtBike magazine the Power Now was tested in.

Thanks.

  • Boit

Posted April 30, 2002 - 12:21 AM

#22

May issue. On page 75 is a photograph of the Power Now and one paragraph about it.

  • brett_h

Posted April 30, 2002 - 02:12 AM

#23

ATTENTION DAVE SIMON: I would like to try your product, but you have not provided any information on how to purchase it. :)

  • fastkevin

Posted April 30, 2002 - 04:31 AM

#24

Originally posted by yz426quad:
]

I'm sorry, the quad/golfcart/waverunner, help I have no sense of balance board, is two doors down the hall. You're not authorized to post here.
:D :)

  • yz426quad

Posted April 30, 2002 - 05:17 AM

#25

Boit,thanks for the info. :)

  • Shawn_Mc

Posted April 30, 2002 - 03:33 PM

#26

After rethinking the idea of air slamming into the back of the slide and having to sneak underneath it, I have an issue with the whole idea. The idea is that the entire atmosphere is trying to get into the carb at part throttle, when I dont believe it is. The throttle is a valve, the valve chokes off the air. Improving the air flow at part throttle will simply throw off the air/fuel curve, will it not? If not, why not? I understand the low pressure issue of pulling fuel, but the fuel is metered for the specific amount of air at that opening. If this were a mass air fuel injection system, it seems this device would cause a high idle, no? The purpose of a carb is to accuately meter air/fuel over the entire range, it seems to me, that improving anything between idle and wide open is done by simply raising the slide, no? The goal of proper atomization and ratio is a noble one, but improving the flow of the carb at partial throttle seems silly to me, not to offend, but please, why wouldnt I just rip the throttle open a little more if I needed it?

  • davesimon

Posted May 01, 2002 - 07:32 PM

#27

Hi. Forgive my tardiness, I work with many things you know. To order, just write me at Worldpower@earthlink.net. Shawn mc, good thinking on the whole thing. You are correct on some accounts, but need to expand ideas on others, which are sometimes hard to explain. The throttle is a valve. Why don't you just open some more? Because you have to slow down to take turns sometimes, and then you have to open the throttle from a low opening to a higher one ALL the time. You always have to drop down to low opening when you ride, so you can always use the extra pull. You kind of answered your own question there. If you want to go faster, you open the throttle further to do what? Give the engine more air by reducing the restriction ( the slide) of the air flow stream. The slide is the restriction to volumetric efficiency and when you are wide open, or have a smooth bore with no slide in the way, the VE is highest. Maybe that will help you understand why at half throttle the power now would increase VE. The back half of the carb is now a smooth bore with no restriction. The air on the top half of the slide that hits the slide just causes turbelence and decreases flow as it tries to mix with the air on the bottom half flowing through the body. With the bore cut in half, the air on the top can not disrupt the forward flowing air on the bottom and VE goes up since the air stream can now move faster. It helps to draw a side view of the carb with the slide in different positions. Then draw incoming air vectors as air would flow. Youfigure out how they have to get aroung the slide and where there force is directed. That will help you see that at the lower openings, more air is turning and hitting the bottom of the throat than getiing under the slide efficiently. The Air/fuel thing has to be later, Sienfeld is on and the White Russian is chillin. A worrd on White Russians, Good to drink, not good to date.

  • twej

Posted May 01, 2002 - 09:30 PM

#28

Jeez I feel stupid

  • Boit

Posted May 01, 2002 - 09:37 PM

#29

Dave, I've asked you via email about the installation process and can't get a straight answer. How about taking a minute or two and describe this procedure. Does the intake bell on the stock FCR carb have to be removed and replaced with the Power Now? What's involved?

  • wrooster

Posted May 02, 2002 - 05:41 PM

#30

The air on the top half of the slide that hits the slide just causes turbelence and decreases flow as it tries to mix with the air on the bottom half flowing through the body. With the bore cut in half, the air on the top can not disrupt the forward flowing air on the bottom and VE goes up since the air stream can now move faster. It helps to draw a side view of the carb with the slide in different positions. Then draw incoming air vectors as air would flow. Youfigure out how they have to get aroung the slide and where there force is directed. That will help you see that at the lower openings, more air is turning and hitting the bottom of the throat than getiing under the slide efficiently.


davesimon,
maybe you could clarify on the other half of the story, namely the eddies/vortices that are created downstream of the slide. some of the air going through the partially opened slide now turns directly upwards and tumbles. it has to due to that pesky "50 year old physics book". so i'm not sure that we are solving the entire "problem" here, as there are two facets to the flow straightening issue per your description. one, "cleaning the flow up" on the upstream side of the slide, and two, cleaning the flow up on the downstream side of the slide. although very cumbersome to implement, the ideal solution here would seem to be a more gradual flow transition through the air metering area. so imagine instead of the "gate" valve there are a pair of ingress/egress ramps -- thus the air flow is meterered much the same as when you pinch a flexible tube rather than the crude gate. the resultant downstream flow is thus less perturbed.

since i'm sure that you have done flow tests using smoke tubes, please point us to some pics of the resultant improvement in flow linearity. if you don't have smoke tubes let me know and i'll send you one manufacturer's name. they're just a couple of bucks each, come in a box of 12, and make a nice white stream. onece you have the tubes then you can cut a window into the carb and watch what is happening to the flow. you'll need to get some light into there to provide good contrast but you can figure out how to do that.

the wrooster

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  • fastkevin

Posted May 02, 2002 - 06:01 PM

#31

Originally posted by davesimon:
Hi. Forgive my tardiness, I work with many things you know. To order, just write me at Worldpower@earthlink.net. Shawn mc, good thinking on the whole thing. You are correct on some accounts, but need to expand ideas on others, which are sometimes hard to explain. The throttle is a valve. Why don't you just open some more? Because you have to slow down to take turns sometimes, and then you have to open the throttle from a low opening to a higher one ALL the time. You always have to drop down to low opening when you ride, so you can always use the extra pull. You kind of answered your own question there. If you want to go faster, you open the throttle further to do what? Give the engine more air by reducing the restriction ( the slide) of the air flow stream. The slide is the restriction to volumetric efficiency and when you are wide open, or have a smooth bore with no slide in the way, the VE is highest. Maybe that will help you understand why at half throttle the power now would increase VE. The back half of the carb is now a smooth bore with no restriction. The air on the top half of the slide that hits the slide just causes turbelence and decreases flow as it tries to mix with the air on the bottom half flowing through the body. With the bore cut in half, the air on the top can not disrupt the forward flowing air on the bottom and VE goes up since the air stream can now move faster. It helps to draw a side view of the carb with the slide in different positions. Then draw incoming air vectors as air would flow. Youfigure out how they have to get aroung the slide and where there force is directed. That will help you see that at the lower openings, more air is turning and hitting the bottom of the throat than getiing under the slide efficiently. The Air/fuel thing has to be later, Sienfeld is on and the White Russian is chillin. A worrd on White Russians, Good to drink, not good to date.


What he said
:)

  • Shawn_Mc

Posted May 03, 2002 - 08:50 AM

#32

I like this Wooster guy! Ive also come up with another question, more of a sideline really. How come /why hasn't anyone invented a carburator with a valve like a camera shutter?

  • wrooster

Posted May 04, 2002 - 10:37 AM

#33

hey shawn, you mean like an old-fashioned leaf shutter? probably no one has used it for the same reason that modern cameras don't anymore -- leaf shutters are finicky and generally less reliable than dual curtain shutters. [ok, now i can hear the hassablad crowd stirring. or was it leitz or leica who hung on so long?]

anyway, by the time we finish this argument all of our bikes are going to have fuel injection anyway. then, instead of "hey have you tried using a 180 main along with another notch up on the needle?", it will be, "hey have you downloaded ferry's new fuel map?" :)

the wrooster

  • Uncle_Rich

Posted May 04, 2002 - 12:54 PM

#34

Hey didn't Ossa use a split bore carb. like 30 years ago ?

Rich

  • Premix?

Posted May 06, 2002 - 04:55 PM

#35

Fastkevin,

Did you have a bad experience with a Russian?

  • Premix?

Posted May 06, 2002 - 05:10 PM

#36

Ooops sorry.....

My last question was supposed o be directed to DaveSimon. Dave how are the Russian women??

  • BALZEE_450

Posted May 07, 2002 - 11:30 AM

#37

Believe it or not it works. I just had one put in my crf 450 and it made a BIG difference. you can read more on the crf forum under Power Now resultes.

  • Victor_Delgadillo

Posted May 07, 2002 - 12:10 PM

#38

I would like to buy it.... if....

some body here explain to me with pictures... i'm too sloowww and the only thing i understand is:

Money
Degrees
Air Flow
Russian Women :)
Air box
Throttle

  • sirthumpalot

Posted May 07, 2002 - 01:36 PM

#39

Pardon me for joining the thread late, but I'm pondering something. If I understand correctly, the main idea of this thing is to increase power at throttle openings less than full open (is this correct?). Why not just turn the grip a little further? At less than full open, if you want more power just turn the grip some more. At full open it looks like a pretty strait shot to me. Am I missing something?

  • Fastest1

Posted May 07, 2002 - 03:53 PM

#40

Carburetors depend on vacuum to operate. The power now increases the velocity of the incoming air by decreasing the orifice size. it makes the carburetor more responsive. Cya





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