FMF product information

Mike from FMF sent me this info on some of the new FMF products including the new Power Core IV-2 SA (Spart Arrester). I'm not sure who performed the tests but it is certainly interesting. The test was done on a YZ426.


Power Core IV-2 Spart Arrestor Part # Y-421 $289.99

Exhaust note is quieter than stock. You can tell immediately even though it's fully forestry legal that there is a huge and very rideable performance for the YZ 426. Performance is focused towards improved bottom to mid-range power designed for the off-roader. The majority of the power increase was distributed through the lower to mid sections of the power band, while still improving the 426's over rev. This new unit has the Power Core IV-2 S/A 3/4 length wing installed and power does not suffer though the DB level was corralled.

Power Core IV-2 Part # Y-420 $269.99

Exhaust note is 2-3 dbs quieter than stock. You can tell immediately that there is a huge and very rideable performance for the YZ 426. The majority of the power increase was designed for the motocrosser, improving bottom end over stock, while focusing most of the power in the mid to top-end regions. This new unit is a straight through design, that is constructed out of FMF's exclusive square core.

Power Bomb Header Part # Y-421H $189.99

The stainless steel Power Bomb unit was originally designed to offset noise penalties associated with a higher flow rear exhaust unit. FMF's Power Bomb knocks 3-5 DB off the meter and makes for a very realistic power gain-mainly bottom to mid range. With the trademarked Power Bomb, FMF realized that the evacuation of sonics gained considerably with the expansion and cooling of exhaust gases into the bomb, then have it recharge to provide a gain in flow characteristics. No loss here, and all gain!

FMF AOF Ignition Part #43-84-02 $399.95

The new AOF Ignition keys in on the TPS (throttle position sensor) and uses the supplied information to select the necessary of three curves available during acceleration. During lower RPM, the AOF ignition will use a curve to improve throttle response and torque. When the throttle is opened up, the AOF will supply a curve to improve mid-range which increase acceleration, and improves top-end in the WOT position. Using the handle bar mounted switch, the rider can select between a top-end "Boost" mode or a torque supplying "Torque" mode. With 2 modes, and three throttle position sensitive curves per each mode, the AOF Ignition will increase power across no matter what the situation.


FMF Power Core IV2 spark arrestor: 5.06 lbs.

Stock muffler: 5.76 lbs

FMF Racing

18033 South Santa Fe Ave

Rancho Dominguez, Ca 90221


Bryan that's cool he sent you back some info on the FMF Equipment. Has anyone out there tried the Power Bomb header yet? I would like to reduce some noise from my e-Series but not lose power. Has anyone found any other "tricks" to make them run quieter?

I expect to see that PCIV-2 SA on your bike the next time we ride and I expect you to tell me it was worth $300.


Dougie, '99 WR400

Mods: YZ timing, Race Tech Suspension, FMF PC IV, FMF Hi FLo Moto, YZ seat, IMS 3.3 tank, One Industries Graphics

I'm waiting for KerryT to buy one!

I've had a Power Bomb on order for about two months now so I can change the oil filter without removing the pipe. Once I get it, I'll let anyone interested know how it performs with the stock uncorked silencer.

Rumor Warning... What follows is unsubstantiated rumor!

Supposedly, FMF has held distribution of the silencers since they don’t technically live up to the hype. I didn’t get any comment on the headers.

I have been asking all sorts of people about these new FMF products – PowerBomb and PowerCore IV squared. I am sincerely trying to quiet the beast. No one really knows for sure. It’s all speculation at this point, but with the interest I’ve seen on this board and others, FMF could dominate the market, if the hype holds true. Think of it, better performance at less than 120 dB…

Best wishes FMF! I’ll wait for you.

To WR400_Jay. You can quiet the E series with the White Bros Quiet core. I posted results a few days ago. At any rate The quiet core does substantially quiet the E Series 5 to 6 db's, however there was power loss. IT was worth the $39 try. My 3rd gear hit virtually disappeared on the MX track. For trail riding I think it will be fine, but definately not for MX. I to am anxious to here about the superbomb. I would like to know results and see how it would react with the E series. I believe if it works along with a few disks removed (down to 8 to 10) my bike may pass the ranger who tests here in No Cal. Waiting to see like the rest.


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