Slip-On for CRF450x

Hey, I finally got my 450x!!! Its amazing how much get up and go it has... almost like a 2 stroke... Anyways, I was gunna ask yall what slip-on I should get for it.\? I was gunna get a full exhaust kit, but the guy at the shop said that the factory pipe was as good as it gets... ?????

before you get rid of the pipe that is wonderfully quiet try a JD jet kit or just change the needle and you'll get some very impressive gains. I love the stealthy nature of the stock pipe, nothing pisses non riders off more than a loud pipe.

I agree!!!!!!!!!!!!!!!!! :naughty:

You won't gain much by going to an aftermarket exhaust except for a lot of noise. If you want more power do what others have suggested, a JD jet kit and maybe open up the airbox a little bit. The 450X motor has smaller valves and different cam timing and can't flow as much air as the 450R, so opening up the exhaust will not necessarily help it much. It was designed to run well with the stock exhaust system, and the power is amazing (around 45 hp) considering how quiet the bike is.

If you must get a slip-on then at least get one of the quieter ones like the FMF Q2.

try the jd jet kit you'll be happy with the results. :naughty: I too enjoy the bike quiet,it's a blast passing someone without them hearing you coming from behind. :naughty:

I am running th FMF Q2 and it's great just a little louder than stock and a good 5 pounds lighter than the stock slip on muffler. That was my main reason for changing the exhaust.

Someone said something about a needle and cutting the airbox??? What do I need to do to the airbox, and where is this needle?

Here is the needle info.

The airbox cutting is the black plastic on the acces side of your air box. There is a black section framed by the white on the side plate, do the same on both sides.

Someone said something about a needle and cutting the airbox??? What do I need to do to the airbox, and where is this needle?

These mods should be done at the same time to be effective. :naughty:

try jd's kit it works great..........

Well guys, thanks alot for all the info!!! Ill try to get them done and get yall some pics!!! See ya on the trails!!!

Pick your self up a legal slip on like a RS3 Yoshimura with a 94db TEC kit, leave the jetting alone unless its not jetted right and enjoy your bike.

As far as JD Jetting go's, I have purchased 2 kits for 2 different kinds of bikes and it didn't do squat as far as performance, so if your bike isn't jetted right, but a $5.00 jet and jet it right. (DUH)

Or spend $70 bucks, buy some jets spend 2 hours re-jetting your bike to the exact same specs its jetted at now and tell everyone how much better you think it runs :naughty:


c u later

I put a White Bros. E2 silencer on my CRF450X. Picked it up at It sounds great, looks very nice, has a removable USFS approved spark arrestor. It seems to improve the power, but that could be psychological. Louder is faster, right? :naughty:

:naughty::naughty: Even tho the 450X is detuned as listed above I disagree with the fact that it can not be made to run better by opening the exhaust with good air flow and carb mods.

The head pipe bend is probably fine to maintain low and mid performance for the type of riding it was designed for, but the stock muffler is heavy and restrictive no matter what the dealer or anyone else says.

The question is now how can you get performance, a little weight savings and keep the sound down plus be forrestry noise level approved 96DB or less.

I suggest you take a look at the White Brothers E2 second generation slip on muffler, you can run it wide open or install the 96DB forestry approved insert with spark arrester in about 5 seconds with one allen bolt. Even with the insert in it flows better than the stock muffler.

I have one on my 05 450R so I can ride in noise restricted areas just by popping in the 96DB insert, it's a well built pipe and gives me the options I need in an attractive well built package.

It came with the suggested main jet to run and said no other changes required on the 450R. The 450X may need a jet kit for the carb due to it being detuned, there is also a smog pump removal kit made to remove the smog pump crap that Honda put on the 450X

They make an E2 for the 450X, do your self a favor and take a look at it.

Good Luck

Bill G

Louder SUCKS wake up and smell the land closures dummy. and for those who have experieced blowing buy a guy @ 80mph who can't hear you coming cuz his bikes to friggin loud, I salute you!! nothing like seeing the whole bike "FLINCH" :naughty:


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