Just got an '03 WR450f a few weeks ago and have got so much help from the members on Thumper Talk. Just joined the forums tonight so I could search the posts. I am trying to figure out how to know if the restrictor plate has been removed from my air box. I need to know so that I can select the correct jet to install. Am I just supposed to remove the plastic that is between the two ports that go down toward the air filter? Thanks in advance for any help you can offer.
New to Thumper Talk
Posted October 12, 2013 - 06:21 AM
Okay, I think I figured it out. I went ahead and pulled out the whole plastic piece with the two snorkels that go down toward the AF. I will go ahead and jet accordingly. The new "performance" jet kit from Dynojet says to use #138 and then add +8 (#146) without the restrictor plate. Weird thing is, the stock jet was #160.
Posted October 12, 2013 - 06:10 PM
You should avoid the dynojet kits if possible.'
Lots of poorly made jets are in those kits, making tuning a pain.
JD Jetting or follow the pinned posts at the top of the forum.
The stock jetting on a WR is not a 160, so someone already changed it.
It's the pilot, needle, exhaust, intake that need to be addressed AT THE SAME TIME.
You can;t just fix one part of the puzzle and expect positive results.