04 YZ250F questions

[YoTRacer158]

first of all, does anyone have or know where i can get any dyno charts for a YZ250F equipped with a powernow/powernow plus/powernow system?

second, the stock filter cage has a backfire screen on it...so if i take the baffle out of the airbox do i need to worry about getting one of the fire-proof filters or will it be fine? thanks for the help

 

[Rich Rohrich]

first of all, does anyone have or know where i can get any dyno charts for a YZ250F equipped with a powernow/powernow plus/powernow system?

I haven't seen one from anyone reputable. The intake velocity is high enough on the 250f that jacking up the signal that the needle sees isn't likely to help in any significant way.

second, the stock filter cage has a backfire screen on it...so if i take the baffle out of the airbox do i need to worry about getting one of the fire-proof filters or will it be fine? thanks for the help

There isn't some big chunk of horsepower hiding in that back fire screen regardless of what some of the internet wanks might want to tell you. But if you do decide to remove the screen it is in your best interest to use a proper flame retardent filter like the Twin Air or BillyWho version.

 

[YoTRacer158]

i wasnt expecting massive gains or anything...just figured any free horsepower is worth having

 

[Rich Rohrich]

i wasnt expecting massive gains or anything...just figured any free horsepower is worth having

If you are looking for free horsepower I'm afraid you'll be disappointed with this approach.

 

[Science]

Have to agree w/Rich on this one.
I had a PowerNow & Vortex X10 on my '03. I tried the PN first and it made a little difference. Felt like it picked up off the bottom better. Then the Vortex by itself and it really worked well. Wow! Not sure if the HP increased by much, but it made it harder hitting. Both made the bike awesome & def were not free! If I had kept the bike the next step would've been a DRD pipe.
BTW, my buddy had an RPM 302 kit installed in his '04 YZF & they flat out told him to lose the PN as it does nothing for the powerband.

 

[gonzo843]

I put the powernow and filter on my 04 and it really didnt do a whole lot. The powernow did nothing. If your not a lugger (which most 250F riders arent) then it doesnt do anything for you. It's a low end device. And the backfire filter in my opinion is waste too. Basically what you lose in screen you pick up in fire retardant mesh on the filter. The only benefit is you dont get rim grease on the screen anymore. If you do decide to do this mod save yourself some money and get a YZ250 filter cage its the same thing for 20 bucks vs 120.