Which YZ exhausts will fit an 06WR450F?

[The Fanatic]

Based on posts I've read, the stock yz muffler would be an upgrade from the stock wR. I'd like to try a stock YZ 450 exhaust before I rip the guts out of the stock WR muffler, or spend more money on a Dubach or FMF system.(my wife might kill me in my sleep

I'm not sure which years are compatible. any help will be greatly appreciated.

I also saw a post mention a yfz/or yzf muffler?? will other model mufflers work?

Thanks, Dave

[OneToGo]

03 to 05 year YZ engine and frame are similar in layout to 03 to 06 WR. The YZ went alloy frame and new engine layout in 06 so that model stands alone.

06 WRs have had brake, bar and other minor changes.

To that end, the exhaust should fit your WR provided it is from 05 YZ 450 or earlier.

The YZ slip on should be a big improvement over the standard WR.

[andy666]

I had a 04 yz pipe on my 06 wr fit perfect.

[odonnks]

Before you spend the $$ try the removal of internal baffels on your stocker. It'll make a difference.

ME, I removed the second baffel (the one tackwelded inside closest to the tail pipe. Took about 1/2 hour and once the endcap is reinstalled you cannot tell.

Then you can have a varity of tuning avail:

Run without arrestor and without tail pipe. Big difference in loudness and power Needs rejet

Add arrestor and still not tail pipe. Sharp brrrraappppp is attenuated but still will need jetting

Add arrestor and tailpipe. Not too much different than before, A little louder on top. may or may not need jetting, depends on how rich you were before.

All is assuming you had a decently jetted bike before.

I usually run with the arrestor and a PMB insert.

There is a thread here somewhere that has pictures.

https://www.thumpertalk.com/forum/showthread.php?t=367721

[The Fanatic]

I'm gonna modify my stocker sunday and see how she runs. I'm a little concerned about getting the jetting dialed in for maximum power (hopefully Indy's jetting guide will get me close)...

I'll also keep my eyes open for a yz exhaust if I can find one cheap, just to compare power delivery.

Thanks for your help!

WR 450's RULE!!! BWAAAAAAaaaAAAaaaAA