I love my YZ450F

[DrNation86]

I have a 04 with Marshalls Racing Suspension, FMF PowerCore 4.1 With PowerBomb Headpipe, DNA Racing Wheels

[f150jokerstyle]

Purdy!

[kiessel24]

How do you like the 4.1? Is it loud?

[DMC707]

Another Okie --- cool ! nice lookin bike

[FinchFan194]

I loved my 04, the perfect gear box/engine power delivery IMO.

[yz133rider]

Ive been considering polishing my engine covers lately and seeing yours sealed the deal for me. Busting out the sand paper!

[DrNation86]

The 4.1 sounds great. Not too loud. Thanks for the comments it was just a random thought of the day i decided to post lol

[gunnin88]

I run the 4.1 on my 2010 and it's very loud. people do not like to ride behind me.

[kiessel24]

You running it with the spark arrestor?

[slothman]

Ive been considering polishing my engine covers lately and seeing yours sealed the deal for me. Busting out the sand paper!

agreed !

[DrNation86]

No spark arrestor

[gunnin88]

You running it with the spark arrestor?

yes arrestor did not make any noticable diffrence.

[kiessel24]

yes arrestor did not make any noticable diffrence.

I just ordered the 4.1 along with the quite insert. It says it'll lower it to around 94db. So we'll see how it performs

Edited April 4, 2013 by kiessel24

[f150jokerstyle]

I just ordered the 4.1 along with the quiet insert. It says it'll lower it to around 94db. So we'll see how it performs

I have the ti 4 muffler and with the quite core in it it still blows around 98db. mine is a 03 the older 450's were simply not built with noise in mind I think. I'v heard the mega bomb helps 1 or 2db but i'm running the stock one.

[kiessel24]

I have the ti 4 muffler and with the quite core in it it still blows around 98db. mine is a 03 the older 450's were simply not built with noise in mind I think. I'v heard the mega bomb helps 1 or 2db but i'm running the stock one.

I have a 2010 and can't afford a whole new system yet but eventually I'll get a new header too.

[f150jokerstyle]

I have a 2010 and can't afford a whole new system yet but eventually I'll get a new header too.

You should be good then I think FMF's data is based off the newer bikes. Also i'v read on here the stock header on your bike is pretty darn good if I remember right.

[kiessel24]

You should be good then I think FMF's data is based off the newer bikes. Also i'v read on here the stock header on your bike is pretty darn good if I remember right.

Yeah I heard something like that too. Once I get it ill let you guys know how it performs.

[gunnin88]

the quite core robs big HP from what I understand. I ride Tahuya national forest and have been checked by DNR guys before they have never mentioned that my bike was to loud but I'm also tail riding so it's not getting opened up all that much.

[kiessel24]

the quite core robs big HP from what I understand. I ride Tahuya national forest and have been checked by DNR guys before they have never mentioned that my bike was to loud but I'm also tail riding so it's not getting opened up all that much.

The insert that comes with my exhaust is both the spark arrestor and quite core. It's all one piece so I don't really have a choice.

Edited April 4, 2013 by kiessel24

[gunnin88]

they sell just a spark arrestor, its what I bought I think it was 28 bucks, I'll find a link

Edited April 4, 2013 by gunnin88