Rocky Mountain Dirt Riders

For my 2007 YZ250

What would y'all reccomend and why?

All bush riding............I was thinking of getting the FMF Gnarly. would I have to drastically change jetting?

Thanks for all input and suggestions.

Cheers,

Giles

I have a gnarly on my 07 YZ and really like it - I did not have to make big jetting changes.

I left the stock pipe and used the boysen dual stage reeds to "spark" up the bottom end a little. Wound up with nice smooth power down low and still have a good hit on top. (Saved some coin too..)

Thanks Tirtyseven........yup have the Boysen 2 stage reeds..........I can get a Gnarly pipe for $20.00 more than a stock one though so I think I am going that route..........talked with a few people and apparently where i munged my pipe is pretty hard to repair without cutting and rewelding.........always wanted an excuse to buy a gnarly!!

Cheers,

Giles

It all depends on what your after and where in the power band.

Stock: Low end and overrev.
Gnarly: Low end, less overrev.
DEP: Best rounded pipe. Pricy though.
PC: mid and top.

If you wanted only low end than you are probably better with the 06+ stocker.

Put the Gnarly on and rode last weekend.........runs great! a little louder tho.......

I have the bike fairly moded too........liked the stock pipe.........love the Gnarly.

What do you mean by over rev?

Cheers,

Giles

Giles wrote:Put the Gnarly on and rode last weekend.........runs great! a little louder tho.......

I have the bike fairly moded too........liked the stock pipe.........love the Gnarly.

What do you mean by over rev?

Cheers,

Giles

Your bike does not have a rev limiter so once the bike hits a certain exhaust resonance factored with your port timing it stops your bike from reving out further. Certain pipes allow more room and some take away from stock. I think the gnarly takes a way a little. You will notice by the bike not reving out as far. It's not a huge difference but it can be felt.

HollywoodMX wrote:
Your bike does not have a rev limiter so once the bike hits a certain exhaust resonance factored with your port timing it stops your bike from reving out further. Certain pipes allow more room and some take away from stock. I think the gnarly takes a way a little. You will notice by the bike not reving out as far. It's not a huge difference but it can be felt.

Great explaination

I've had quite a few YZ's before I went orange and the best set up I had in my opinion was a gnarly pipe, v-force reed valve, and a 9 oz. flywheel weight. Still not the same smooth power delivery as a KTM but as close as it gets.