Top to bottom -
Leo Vince X3
STOCK WR 2007
White Bros XCR
In terms of power gain.. (most at top)
07 YZ450F tied w/ White Bros XCR
09 YZ450F (W/PMB end cap +silent core/tip and inner stock restrictive baffles removed) tied w/ Leo Vince w/silent tip
09 YZ450f STOCK
terms of Volume (loudest at top)
09 YZ450F STOCK
Leo Vince (unplugged)
09 YZ450F modded
White Bros XCR
Leo Vince (silent tip)
WR w/ pea shooter out
The first pipe I tried was the XCR. It was nice and peppy, quiet, a good pipe... but BIG! it sticks out too far for me. Good pipe if you dont mind the size/length. I didn't bother doing a lot of testing, as I knew it would not work well with my saddlebags. I am selling it.
Next I tried the Leo Vince. Nice nice pipe. sounds good, probably the best power out of the bunch. BUT it was too loud without the quiet insert, and with the quiet insert it lost its edge of power over the YZF pipe. Also, the quiet insert cannot be used in conjunction with the spark arrestor. IF you don't mind a little volume, your best bet is the Leo Vince. I would guess it is around 96DB opened up. Too loud for me. The quality is fantastic however, I will keep it as a backup if I bash mine.
Next I rigged up the 09 YZ450F system. I put the PMB spark arrestor, quiet insert, and quiet tip on. I really liked this setup, but it was still a bit too loud for me. I would guess it was around 94-95db. Sounded nice, good power compare to the Leo even. Nice and short, out of the way. Just a bit too loud. I am going to sell it.
Then finally I tried the 07 YZ450F pipe. I already had the 09 YZ450F large diameter header on. I put a spark arrestor on to make sure I am legal.
Fired her up and took her for a spin.. This is the one! VERY quiet... 2nd quietest to the stock WR pipe. Power would be just behind the Leo Vince unplugged. A hair more power than the 09 YZ450F system with the silent core + tip, but still much quieter. The sound is great, a little bark when you get on it, but purr quiet when you are just cruising. When I ride hard I still hear the sound coming directly from the motor more so than the exhaust.
When I get more time I will take a video of the Leo Vince to compare.
ALSO, I was not able to try a FMF Q4 on this bike.. however, I had one on my XR650L and on my XR250. They work well, however the spark arrestor design on them is fairly restrictive, and the quality is not quite as good as I would as I would want. On the XR650L, the FMF Q4 was fairly loud. But that is apples to oranges comparing to the WR450. YMMV. I believe the YZ450F pipe is a better value.
As you can tell it looks much like the Stock WR but it is much much lighter
Leo Vince with quiet insert VS 07 YZ450F exit pipe diameter. As you can see the YZF pipe is significantly larger. However, without the insert the LV is larger in diameter than the YZF pipe.
Edited by n16ht5, April 22, 2012 - 09:43 PM.