Daily Hook Up - FMF Factory 4.1 System
Brendan Lutes
- June 30 2009
- 2,485 views
- 17 comments
FMF FACTORY 4.1 FULL-TITANIUM SYSTEM WITH MEGABOMB HEADER
APPLICATION: Available for most late-model mxers (Tested here on the 2009 KX450F)
OPTIONS: Available with either Megabomb or Powerbomb header. Mufflers available in natural or blue anodized
PRICE: $849.99
KEY FEATURES:
-Made from high quality titanium
-Features exclusive proprietary Chamber Core technology
-94db insert and spark arrestor insert available
-Designed to boost power all throughout the powerband
-Utilizes what FMF calls Factory-Forward Technology to centralize mass and improve handling. Something that not many exhaust companies consider when producing an exhaust system
WHAT WE LIKED:
-Solid construction
-Fitment is excellent
-The full titanium system is much lighter than stock
-Power is improved, giving our 2009 KX450F more grunt down low with a noticeable increase in top-end pull
-Pipe isn’t overly loud
-Looks clean when mounted on the bike
WHAT WE DIDN’T LIKE:
-The price is high, however, on the ’09 KX450F you do get what you pay for—a high-end exhaust system that produces power and performance gains. FMF also offers slip-on mufflers that we’ve tested with impressive results
WHAT WE REALLY THINK: If you’re looking to get some extra power out of your 2009 KX450F, you should probably consider the FMF Factory 4.1 system with the Megabomb header. It looks good, produces noticeable power gains, and will likely stand up to a lot of abuse—ours has so far. Your hand earned dough will likely not go to waste if you decide to update your bike with this setup.
Visit www.fmfracing.com for more information
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June 30th, 2009 at 11:08 pm
Every FMF exhaust system i have owned has fallen apart a third of the way through the season. the mega bombs welds split apart and the silencer mount rivets break
June 30th, 2009 at 11:14 pm
I currently have the pro-circuit 2009 ti-4R full exhaust system for my 2009 kx450f, and it's amazing! pro-circuit exhausts are way better than FMF.
June 30th, 2009 at 11:29 pm
I like the mega bomb just because it looks so trick. Makes me feel like I have a little factory unobtainium on my bike. My 450 has more power than I can use safely anyway wich is the case for most. Great product.
July 1st, 2009 at 12:08 am
Earlier this year I purchased a 4.1 with a Powerbomb for my 2007 RMZ 450 and I love it! I have had no problems whatsoever and it has not always been rubber side down. Great Buy!!!!!
July 1st, 2009 at 12:09 am
not a great product had 2 4.1 systems and both broke.. the silencers are too brittle. have a pc system now and its 100 times more durable
July 1st, 2009 at 2:55 am
I have been running the FMF systems since 05 and am very pleased with their quality and performance. Everything eventually wears out. Currently running one on my 09 CRF 450 and wow, what a difference. I recommend taking the baffle at the end out.
July 1st, 2009 at 5:38 am
I've got the megabomb but with a powercore muffler on my 06 yz250f. I've never tried any other system but I'll admit this combo really have me a huge hit down low. Seems to be about the same for top end. My only complaints are that the sleeve that fits the header to the mid pipe is loose and it rattles a lot and if you don't use the springs when mounting the megabomb, you could slide it right out of the head.
Other than that I love it!
July 1st, 2009 at 9:34 am
get a leo vince cant go wrong fantastic pipe puts FMF to shame
July 1st, 2009 at 4:36 pm
Had a mega-bomb split in half on me a few months back. The system made the bike (06 YZ250F) feel awesome off the bottom and through mid-range though.
July 1st, 2009 at 4:51 pm
Had my 4.1 with Megabomb on my YZ250F since '07 never an issue. Huge hits down low and throughout the entire powerband. Absolutely love it!!!
July 1st, 2009 at 5:25 pm
GET A Akrapovic THE BEST THE EXPANSION CHAMBER WAAAYYY BETTER
July 1st, 2009 at 7:14 pm
if they are so awesome why did the hart and huntington team (who has leo vince as a team sponsor) stop using it and used yoshi pipes in supercross while they still were in a contract with LV and had LV logos on their bike. Their stuff doesnt sound so great to me, and FMF's look so sick!!!!!!!!!!
July 2nd, 2009 at 1:49 am
4.1 is the best system with the megabomb that ive found so far on my bike (08 YZ450) and ive had a couple of exhaust systems (pc, drd, akrapovic) and FMF kicks the most ass
July 2nd, 2009 at 9:30 am
i run the dual carbon fiber 4.1 system with the mega bomber header its amazing for my crf 250 f plus it doesn't burn my knees in my pant like my stainless steel system! breaking the exhaust has not been an issue and i have had it for a year, but here is a good tip if you didn't fall all the time your exhaust would have stayed together better and probably would be way cheaper for you !!
July 3rd, 2009 at 4:19 am
if your not crashing your not progressing
July 4th, 2009 at 8:10 pm
I have this system on my 06 YZ250f, and I have had it for nearly a year and have had no issues at all so far. Performance wise, I don't know because I had it installed with a big bore kit, but mechanically it's solid. Everyone I know who runs this setup loves it.
July 5th, 2009 at 9:52 am
any tryed a yoshi on a yz250f?