09 YZ450F A little mild for my liking

I just bought a brand new 09 450 and find that it is laking in the power department. It definitely does not have the snap that my 03 Gas Gas 450 with FI did. Are there any cheap/free mods to uncork this thing? I don't really want to spend a bunch of money on a crappy aftermarket, noise belching pipe. Do I need to remove the back fire screen or any other factory install stuff?

Ditch the shorty muffler and pick up a used CDI from an '06.

I felt the exact same way with my new '09 that I bought this Spring. Here's what I did :

'06 CDI on E-bay $40

'06 Standard carb needle jet

170 main jet

New FMF Powerbomb header on E-bay $64

New Procircuit slip-on E-bay $175

The biggest culprit that robs power is that garbage stock exhaust, check these posts out for info on removing the cone(s) out of the stock exhaust :

http://www.thumpertalk.com/forum/showthread.php?t=866524&highlight=pmb

http://www.thumpertalk.com/forum/showthread.php?t=851003

A cutaway view of the stock exhaust :

http://www.motocrossactionmag.com/ME2/dirmod.asp?sid=&nm=&type=news&mod=News&mid=9A02E3B96F2A415ABC72CB5F516B4C10&tier=3&nid=3C64793A1A204AF0AF3E7ECC2A3CD20C

My bike has a night and day different feel in comparison to when it was stock, I've also put heavier DSP springs in the forks and shock ($149.99 shipped to your door). It's awesome !

My bike has a night and day different feel in comparison to when it was stock, ...

Throw an '06 CDI on it and you'll think there was a third option.
I felt the exact same way with my new '09 that I bought this Spring. Here's what I did :

'06 CDI on E-bay $40

'06 Standard carb needle jet

170 main jet

New FMF Powerbomb header on E-bay $64

New Procircuit slip-on E-bay $175

I put an '06 CDI on it before the hour meter had hit 2 hours.

Missed that. :banana:

what difference does the 06 CDI make?

does the '06 CDI trick also work for the '08 ?

does the '06 CDI trick also work for the '08 ?
Yes.
what difference does the 06 CDI make?
The '06 uses a different timing map that provides more lower mid range through upper mid range power. Those who have tried it say it's pretty remarkable.
Yes.

The '06 uses a different timing map that provides more lower mid range through upper mid range power. Those who have tried it say it's pretty remarkable.

How well does it work with the stock exhaust?

I don't know that anyone's tried that, but you might hear from somebody. My guess is that it will be better, but the stock exhaust is a pile no matter how you look at it.

So you are talking about just a stock 06 CDI? Wow I may give that a try.

I felt the exact same way with my new '09 that I bought this Spring. Here's what I did :

'06 CDI on E-bay $40

'06 Standard carb needle jet

170 main jet

New FMF Powerbomb header on E-bay $64

New Procircuit slip-on E-bay $175

The biggest culprit that robs power is that garbage stock exhaust, check these posts out for info on removing the cone(s) out of the stock exhaust :

http://www.thumpertalk.com/forum/showthread.php?t=866524&highlight=pmb

http://www.thumpertalk.com/forum/showthread.php?t=851003

A cutaway view of the stock exhaust :

http://www.motocrossactionmag.com/ME2/dirmod.asp?sid=&nm=&type=news&mod=News&mid=9A02E3B96F2A415ABC72CB5F516B4C10&tier=3&nid=3C64793A1A204AF0AF3E7ECC2A3CD20C

My bike has a night and day different feel in comparison to when it was stock, I've also put heavier DSP springs in the forks and shock ($149.99 shipped to your door). It's awesome !

where do u find a fmf powerbomb header for 60 bucks, all of them are 170

Will the '06 CDI box help out on an '07 YZ?

More low end, a little less top.

Another cheap fix is to switch to a 50 tooth sprocket.

A twin air filter actually made a difference. I will order the 50 tooth sprocket. I really doesn't need much more for my liking. Just a tad on acceleration.

where do u find a fmf powerbomb header for 60 bucks, all of them are 170

I won it on an auction, I was willing to pay more than double what I actually did. That was one of my better finds on Flea-bay so far this Summer.

I just put in the 06 cdi and not that much of a difference. Already have DRD exhaust and yz250 filter cage with 165 main. I might try the 06 carb needle and a 170 main.

How well does it work with the stock exhaust?

I was riding in higher elevation after I put the 06 CDI on mine with stock exhaust but I did notice more snap on the bottom end.

I just installed an FMF Q4 on my bike and will let you know how it runs after this weekend. I may need to re-jet (I'm now riding around 7,500') but I'll let you know how it did. Funny thing is, at idle, the Q4 seems louder than the stock silencer.

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