Power Now Valve worth it?


10 replies to this topic
  • Smiticus

Posted July 06, 2005 - 09:36 PM

#1

So, I took my 01 426 in to my mechanic due to some rough running at about 1/4 throttle, to the point of killing the motor. He looked through the bike and said that a POwernow valve from scaryfast would do the trick. I know that it will increase my power at lower throttle, but will that actually smooth out the rough riding?

Anyone out there using it and liking it?

  • crfmatt

Posted July 06, 2005 - 10:07 PM

#2

I bought my bike with it so I dont know what it was like before but as far as problems go mines been trouble free.

  • Lukejt

Posted July 07, 2005 - 07:33 AM

#3

I've got one I bought used cheap. I didn't really feel that much of a difference. Sounds like you need to play with some different jetting. A Powernow is not going to cure a rough running bike thats not jetted right.

Also check for any air leaks, make sure the AP is working, and double check the hot start.

Lukejt

  • John_Lorenz

Posted July 07, 2005 - 07:42 AM

#4

I've got one I bought used cheap. I didn't really feel that much of a difference. Sounds like you need to play with some different jetting. A Powernow is not going to cure a rough running bike thats not jetted right.

Also check for any air leaks, make sure the AP is working, and double check the hot start.

Lukejt


I agree with this as well. the 426 is a temperamental beast with jetting, air temp, altitude and general will effect the 426. The best mod you can do is to clean the crap out of your carb, make sure the pilots not clogged and do the GBmod GBmod Write Up

It might help us if you can list some of the following

Pilot Size
Main Size
Needle type and Position

Also a good clean Spark plug is a great choice along with a clean air filter :)

Oh ya back to the powerNot I dont believe in it :) :D

  • grayracer513

Posted July 07, 2005 - 07:51 AM

#5

I have a question: Did you have your carb slide out before the bike started running rough at 1/4 throttle? If so, be sure you put it in facing the right way. Both the slide and the spring plate can be mispositioned, and will cause the bike to run very rich.

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  • 426Climber

Posted July 07, 2005 - 07:59 AM

#6

I noticed a little help on throttle response but not enough to have gone out and spent 100 buck on one. The hell with buyin one make your own. Takes 30min-1hr start to finish

  • Chills

Posted July 07, 2005 - 10:37 AM

#7

I have a Power Now in my '01 426, it seems slightly smoother, but then again I also have the 450 Cam mod in it also. The Power Now has been known to lean the air mixture slightly, but even more when you add the Power Now Plus. If it is serioulsy running rough, I would check the slide to see if its backwards, and thoroughly clean your carb and jet with an air hose.... I like my Power Now personally!!

  • Smiticus

Posted July 07, 2005 - 03:32 PM

#8

Thanks for the input. I cleaned the crap out of the carb' and it runs smooth for the first few minutes and then goes rough. I checked for air leaks and found none, and slide and spring plate are good, so my guess is that I need to check the jets. I'm at about 4700 feet here in Idaho. John_Lorenz, I'll get those specs and thanks for the GBmod info, looks like something to check out.

Thanks guys!!

  • Chills

Posted July 07, 2005 - 04:39 PM

#9

Mine runs the same way when I go up to 6200ft +. I dropped the MJ down to 145, and the PJ down to 40. I think I can even go lower, and maybe adjust the fuel mix screw. Mine has done the same, runs great cold, but when its warm at that altitude, it sputters slightly unless im on the gas... Definately look at the jets

  • Chas_M

Posted July 07, 2005 - 07:39 PM

#10

The Power Now may help the low speed throttle response somewhat, but it also decreases maximum power a little as well due to the slight restriction in maximum air flow through the carb.

  • ovrrdrive

Posted July 08, 2005 - 12:52 AM

#11

Thanks for the input. I cleaned the crap out of the carb' and it runs smooth for the first few minutes and then goes rough.


I'd say take the float bowl off and clean it out and give the carb another good cleaning with spray and a little light compressed air, then take the tank off and drain it and clean it out. Sounds like trash is getting in it from somewhere.

A powernow is not supposed to be a "fix" for a poorly running engine. It is a performance item. If it is running bad, I'd look elsewhere and probably not trust the mechanic that told me to get a PN to fix it anymore....





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