02 YZ426F Exhaust Help?

Killing some time in sunny Iraq and been looking for a new system for the YZ. Just don't want to be doing a bunch of rejetting when I get home, bolt and ride! You guys got any recommendations? And what kind of performance can I expect?

Killing some time in sunny Iraq and been looking for a new system for the YZ. Just don't want to be doing a bunch of rejetting when I get home, bolt and ride! You guys got any recommendations? And what kind of performance can I expect?

Welcome back!

The stocker flows pretty well so most guys don't need to rejet (provided the jetting is good to begin w/).

I tried 4 different aftermarkets on my 2 YZ 426s, a WB R4, PC T4, FMF Q, and a Thunder Alley.

I liked the latter the best, the T4 was the best made/strongest, the Q fell apart. None ran on the top end like the stocker, seemed to lose some of that zip, most improved the low and mid...

To be honest, if I had it to do over again I would just stick w/ the stocker (although I would add a Spark Arrestor insert as I need this from time to time) and spend my money on a suspension revalve.

But I did love the Thunder Alley, I have one on my Honda currently.

Hope this helps.

edited: I didn't have the E series, I had a WB R4, oops.

Forgot to add most are VERY loud, to the point where I wonder if it is worth it. One thing I liked about the Thunder Alley is that the model w/ the Spark Arrestor was not much louder, if any, than stock.

The Q was quiet but you lost some low and mid, and as stated it fell apart on me, so I can't recommend that.

The stocker seems to be the best compromise of noise and power if this matters to you.

Like Hick said, I've got a Yoshimura system and I can't tell much or any difference in power. I think it comes on in the midrange a little harder, but that's all. But, I bought the exhaust cheap and it does say Yoshimura on it...

Save your money and buy a Rekluse auto clutch instead.

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