Power Now valve on r carb

[pdracer440]

Anyone running a power now on the 450r carb? A friend of mine put one on his dirt bike and aid it made a heck of a difference on acceleration. Just wondered if anyone has tried this, and if so what the results were?

[Eviltanker]

I got a boysen power wing, Same concept as the powernow deal. It will richen you up a little( I am back at stock jetting with my mods) and will have you banging the rev limiter ALOT faster than you are used to. So to answer your question it will help.

[pdracer440]

Thanks for the input.

[Eviltanker]

http://shop.boyesen.com/catalog/default.php?cPath=1_72
this might help

[sandmanblue]

On every dyno test run on these things that I have seen, they show a DROP in power.

If it were such a good idea, don't you think that companies like Mikuni and Keihin would have used them in the past, or make them part of the carbs they make now?

It is a restriction in the intake tract. Nothing more - just a chunk of metal.


Sorry, but I'm sick and tired of snake oil products like this, along with the 'turbonator', splitfire plugs, and that stupid thing that makes engine noises through your radio..... All about as useful as using a fork to eat water.....

[Eviltanker]

I'm running a 400EX proto part and I have not lost power. I have picked up better responce off the bottom. I figured I would try it since it was free. I don't trust dyno charts from companies but, I was at boyesen and toured the facility and met with the R&D guys. I saw a dyno chart for a snowmobile and it did give a small gain. not enough to brag about but you will feel a difference in acceleration. I don't understand the point of the second piece though on the scaryfast setup(the piece after the carb)

[chris46250r]

I had the power now on my 450. Took it off and gave it away if that tells you what I think of it.

[underpowered]

i have heard nothing but negative about these types of products. Like sandmanblue said all it does is restrict air flow. if it did help, wouldn't the choke in a stock 400ex carb do essensially the same thing when it is off and sideways in the carb? i have ridden a YFZ with a power now stock vs with it and noticed no difference. IMHO they are not worth it and don't make a difference.

[Eviltanker]

They are designed to be used without the choke. using it with the choke will do nothing.

top end loss using them. Richens jetting from less air flow.

[duneflyer1]

I purposely bought one to do some dyno before and after testing on my bike. It did increase the bottom end pull but 1HP, LOST on the top end by nearly 2HP. Did the same for the torque curve. It WILL help your bike run in the bottom, from about 3g to 6g in RPM, but you loos too much on the top to make it worth it. Now if all you do is putz around and dont get past half throttle, then it will work for you.

Originally posted by duneflyer1
I purposely bought one to do some dyno before and after testing on my bike. It did increase the bottom end pull but 1HP, LOST on the top end by nearly 2HP. Did the same for the torque curve. It WILL help your bike run in the bottom, from about 3g to 6g in RPM, but you loos too much on the top to make it worth it. Now if all you do is putz around and dont get past half throttle, then it will work for you.

XC and some trail is all its good for
. I made a home made one out of a corn can. All i did was cut a square out of it and put it in the carb.

All they do is stop the air from spining around more so it sucks it in faster which would sound like it would help with power all over but it dont. Alot of people say they dont feal a gain. I know a person that had one and felt almost no gain and needed to chaing his main jet 2 sizes.

[underpowered]

Originally posted by Eviltanker
They are designed to be used without the choke. using it with the choke will do nothing.


i know that. i was jsut saying the design of it. i mean it is pretty much just and airfoil in the intake tract. the stock 400ex choke mechanism is pretty much the same thing IMO. shat good would it do?

[Eviltanker]

You are right, I'm not arguing with you. He asked and I gave my opinion on the mater of the power now system. I have something simular and have not had problems with it.