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gripitnripittx

Anyone install a FMF Snap Airwing on a 2012 WR450F?

9 posts in this topic

Hey Thumpers, I have already "uncorked" my 2012 WR450F (Installed a FMF Megabomb Header & FMF Powercore 4 Hex Muffler, installed the short throttle stop screw, competition ECU & removed the airbox snorkels) and I am playing around with the fuel maps...what a HUGE contrast from factory...the bike is now a beast!

 

But like most of us, I'm looking at any other simple/inexpensive "bolt-on" improvements & wanted feedback on the FMF Snap Airwing (https://www.denniskirk.com/dk/pdf/instructions/17/dk173630.pdf) as well as how easy or difficult/involved it actually is to install.

 

Thanks for the feedback!

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Not snake oil, these type of things improve throttle response, but don't increase power. I used a product similar to this back in 2003 on my 2002 YZ250F. It was called Power Now (cheesy name, I know). It only had one horizontal blade, and it made a substantial difference in the throttle response. With this FMF unit having two blades orthogonal to each other I would think that the improvement in throttle response would be even more substantial. The price is pretty steep for what it is though IMO.

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They work in carbs, but mess up the jetting if it is spot on to begin with, because the vacuum is increased for all throttle openings below halfway.

I have one in my carb's WR, and it helps a couple of percent.

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Streamline the end of the cold start plunger.

 

See here:

 

I used gas tank leak fix epoxy.    

 

Between doing the cold start plunger mod, the 08 YZ exhaust cam and setting C1 (to 8), the bottom end on my bike is fantastic. Smooth, predictable, luggable and strong and it never flames out.

 

BTW, its not a choke.  Its an air bleed.  The butterfly on these TBs closes off the bore entirely.   The passage that the cold start knob covers is where the air gets through at idle and high idle when the knob is pulled out.

Edited by MidlifeCrisisGuy
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Not snake oil, these type of things improve throttle response, but don't increase power. I used a product similar to this back in 2003 on my 2002 YZ250F. It was called Power Now (cheesy name, I know). It only had one horizontal blade, and it made a substantial difference in the throttle response.

 

 

On an engine such as the YZ250F, the carb is a bit larger than is beneficial to low RPM response, and the cam timing is considerably more aggressive for an engine of that size.  In terms of power per liter, it's much more high strung than even a YZ450F is (at the same level of tune, a 450 would produce 70 hp).  Bigger engines in milder states of tune don't suffer from the same kind of intake reversion problems as do the little bikes, so devices designed to counteract that don't have as much of an effect on them.  You will not see the same sort of benefit in such devices on a YZ450, much less the WR, as you would on something like an MX 250F.

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Hey Thumpers, I have already "uncorked" my 2012 WR450F (Installed a FMF Megabomb Header & FMF Powercore 4 Hex Muffler, installed the short throttle stop screw, competition ECU & removed the airbox snorkels) and I am playing around with the fuel maps...what a HUGE contrast from factory...the bike is now a beast!

But like most of us, I'm looking at any other simple/inexpensive "bolt-on" improvements & wanted feedback on the FMF Snap Airwing (https://www.denniskirk.com/dk/pdf/instructions/17/dk173630.pdf) as well as how easy or difficult/involved it actually is to install.

Thanks for the feedback!

I have all your same mods plus gytr head and cams. I saw this snap thing for 99 bucks. So I threw it in and I honestly can feel a difference in throttle response. No extra power or anything else but it does help a little.

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I have all your same mods plus gytr head and cams. I saw this snap thing for 99 bucks. So I threw it in and I honestly can feel a difference in throttle response. No extra power or anything else but it does help a little.

Thanks Jonsey11.

How much is involved in the install, the info on FMF 's website is not real clear. I'm assuming you installed yours while you had the bike apart for the head & cams, so may not have been much additional to install.

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Thanks Jonsey11.

How much is involved in the install, the info on FMF 's website is not real clear. I'm assuming you installed yours while you had the bike apart for the head & cams, so may not have been much additional to install.

No did the cam and heads a month or more back just did this one last week. Kind of a pita. You have to pull the subframe to put this piece in the airbox boot that connects to throttle body. Not hard but with all the wires on this bike just time consuming.

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