What exhaust should i get

[MY-BLUE-BEAST]

I ride a 2004 WR450F and the stock exhaust just isnt cutting it anymore. It is very loud and since it is welded and not riveted, it cant be repacked. What exhaust should i get that will give me that nice 4-stroke growl that im looking for, that will also give me a nice performance gain? Any info would be helpful, thanks

[12bruckd]

fmf 4.1 is darn good for me, but i have a yz 450

[2in2out]

FMF Q4 quiet. Under 96 db, but still sounds like a 4 stroke.

[Just_a_trail_rider]

I have tried a couple different pipes for mine, I didn't notice any performance gain that justified the money I spent on it.

Get the Q4 if you need one. Its quiet, which is a good thing.

[Ryan426]

+1 on the Q4

[MY-BLUE-BEAST]

thats what i was hopeing you guys would say, but one more question, should i get a megabomb or powerbomb header?

[2in2out]

After having both the PB and MB, I would go with the PB header in SS. If you ding it it can be reshaped, and the PB gave more low end grunt in my experience.

[WR450FGreg]

.

Used YZ450F systems are much better than OEM WR units and cheap-as-chips on fleabay.

I went that way.

Greg

[MY-BLUE-BEAST]

Will i have to get the same year of YZ exhaust to match my bike?

[MaxPower]

I like the stock YZ pipe also

If you can find a good conditon OEM pipe you will be set.

I dont care what anyone says. The fit and finish of a OEM pipe is worlds better than aftermarket pipes.

a 03 04 and 05 pipe will jump right on. No need for a header as you have a nice and light Ti header that comes stock.

[desdave]

Even though I have aftermarket on my 08, I agree that stock YZ is gonna give the same result for cheaper if you can find one on ebay. Also, Pro Moto Billet and a couple of others make spark arrester add ons if you need that in your area.

[pcarnut]

Timely question. I'm just getting back into dirt riding again and recall seeing a comparison review of slip-ons for 4-strokes not too long ago by one of the dirt mags. Have tried several different search parameters but not getting a direct hit. Does anyone remember this article and if so, where? Thx!

[Just_a_trail_rider]

thats what i was hopeing you guys would say, but one more question, should i get a megabomb or powerbomb header?

Neither one. You will not notice the difference. I have a titanium megabomb header in my garage that I never put back on after I dented it. (Its very soft btw) I have nicely dented titanium FMF pipe and header that I had had to get repaird several times. Never any damage to the stock. Its a little heavier. But if you wanted a lightweight bike, you should not be riding a wr450.

If your money is burning a hole in your pocket and you have to buy something, I would buy a muffler before the header. I have an 05, so I was able to open up my exhaust and let it breathe quite a bit. Get one of those and save yourself a ton of money. The FMF will look cooler for sure, but you won't go any faster after you spend the $400 bucks.

If you want real performance upgrades, take the exhaust/header money and buy some cams. Then get all the accessories to dial in the carb. That was money well spent after I wasted $800 on exhausts.

[MY-BLUE-BEAST]

Sweet, thanks for the info. I found a 2003 YZ450F muffle and midpipe in the classifieds here at TT for $50, he pulled it off right away when he got the bike and got aftermarket exhaust.

[WR450FGreg]

.

I found a 2003 YZ450F muffle and midpipe in the classifieds here at TT for $50, he pulled it off right away when he got the bike and got aftermarket exhaust.

Perfect!

Now I'd ride someone else's bike fitted with an aftermarket exhaust before I considered buying one if I were you.

I bet you stick with your $50 YZ system!

Greg

[MY-BLUE-BEAST]

One problem with it though, it doesnt have a spark arrester, and i dont know which kind to get and where to find one, any help?

[Just_a_trail_rider]

One problem with it though, it doesnt have a spark arrester, and i dont know which kind to get and where to find one, any help?

Here is what you need.

http://www.amazon.com/2003-2005-YAMAHA-YZ450F-SPARK-ARRESTOR/dp/B002FDTY16

I suspect you'll have to rejet with the yz exhaust. Just do all the free mods and check the jetting guide and you'll be fine. The yz exhaust is free flowing, but a bit noisy.

[12bruckd]

i think yamaha GYTR makes a spark arrestor insert for the yz, im not sure if its only for the GYTR exhaust thought. but that option is only like 30-40$. might be worth looking onto.

[Jason Stevens]

I recently put a Leo Vince slip on can on my WR. It is very quiet, at 94db's, you actually hear more engine noise than exhaust. I bought it a the recent Nat'l enduro in central Arkansas. Ted Campbell is a the Nat'l race mgr for L.V. and was great to deal with, i would send anyone his way for a great quality exhaust.

[MY-BLUE-BEAST]

That cap isnt a bad price, and i would spend a whole $179 bucks for an exhaust system rather than $400+. I already did all the free mods and i have YZ jetting in my bike already, so i should just be able to throw it on and go.