250-500cc scary fast powernow plus wr300

Has anyone tried the scary fast powernow on the wr300 ?

A waste of money/gimmick IMHO. If it was that effective for such a low price don't you think the manufacturers would all be using it?

your better off getting your bike jetted "properly" if not already
I ignored jetting for years not realizing how huge a a boost of power was missing in my bikes

divider plates work, they're for idle -> low/mid response. basically mimicking a smaller carb at lower throttle openings. if you think 'ScaryFast' is a gimmick, have Ron Black do a divider plate mod for you instead. $85

i've had them on my WR and TC, both made a nice improvement just off idle to half throttle.

I have done jetting on it i have pulled the carby appart so many times i lost count but it still has a slight sputter off idle

Is this metal piece a power-now device? I inherited this piece and don't really know what it is ..

I can only assume from the shape of it, that it limits the airflow into the carb up to half throttle, making the mixture up to that throttle opening richer? Surely the same could be achieved with jetting?
Not having a go for the guys that have it, but IMO it looks like a "band-aid" solution?

I have one of those in a box of garbage ! Came of my mate Trigs Husky, did not do a thing -- But on the other hand when the carb was modded to have a divider plate on the other side of the slide (reed side ) the same as a rb mod there was a marked improvement on all small throttle openings - Top end was identical to before the fitment.

ray_ray, that's the PowerNow, it installs on the airbox side of the carb.

johnnyboy, correct, better to have a divider plate on the reed side. ScaryFast calls that the PowerNow Plus.

It doesn't make it richer. In theory is decreases turbulence because it blocks off the "unused" part of the carb's throat at low throttle openings. I know nothing about actual effectiveness.

Ron Black wouldn't waste his time doing the mod if he didn't think divider plates work... but having said that, the PowerNow Plus does need to slide into your existing carb bore. how that effects performance vs a plate alone, i don't know.

shane13, i have a brand new PowerNow Plus (reed side) if you're interested and it fits your Mikuni. i moved to a Lectron carb.

Thanks and thought it was a powernow but not sure ....Here's what that thing does for my 08 WR250cc Husky ..

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As stated before, my bike screams as a 250cc 2t bike should out the topside with the PC pipe and its does load-up at a few specific RPMs before it gets on the pipe ... Don't really care that it is not jetted 100% other than the exhaust drool ... I just stay off that RPM ... Another plus for a 2t bike over a 4t bike maybe ...

One day, I left that device out by accident and rode the bike a few days without it ... My short term memory is very bad and I forgot that I left the piece out ... So I did not really pay alot of attention to the bikes behavior overall while riding without it. But, it was 100% apparent that my bike lost ~1/2 its low end power and REVs were a little slower at low RPMs without the piece.

I would definitely have to re-jet to try to boost the bike up if I did not have that powerNow thing. Once on the pipe, no real changes I think ... After riding a few days without the device, I saw it laying in the garage and knew instantly why the power was low and it went back into the bike. Its back to my normal, 250cc, 2t, Husqvarna, dirt-bike now.

Not sure if the starting was worst or not because I can't remember ... My bike starts 1-2 kicks 99.9% of time, even after crashes ... So if my bikes needs 3 kicks, something is wrong ... Its a 1 kicker ~always if you kick it like a 2t bike wants to be kicked with the hand-full of throttle. 4t girly push-downs on the kicker? Not allowed here

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My dilemma now is will re-jetting help my bottom end more or not? Next time I remove the CARB, I'll look at the jets but it is not a priority ... In my case, the rider is the deciding factor most ~all of the time, not the hardware.

should have no effect on jetting (stated by the designer) as well as not effecting WOT (everything is open at WOT).
I had both sides PN and PN+ and are they still on my sold off 4 strokes 06 TE450 and 08 TXC450.
Very noticable* on super ugly rock climbs coming from closed to mid throttle, the 4 strokes were smoother and more torqy/just felt cleaner in carburation, makes sense what was felt by the nature of the design.

*I backed to back TEs one with, one without, the feel was very noticable and I think for beginner/novice riders these type of devices are a super good mod.
Again for me they were effective when hung up coming off almost closed throttle to continue smoothly or climbing some near vert rocky stream bed/waterfall or AA loop trail using a higher gear to smooth power but getting better carb velocity and torque at lower throttle plate openings. They are bottom end torque supplemental device (my PN/PN+ experience is only on 450 twin cam Husky 4Ts Keihin FCRs).
Carbs were set up with standard book setting JD Jetting, AP oring, leak jet setting, PN and PN+, scary fast AP cover, extended mix screw.