Hey guys just thought I would share what I did to my 2014 YZ 450 the other day.
I know the 2015's came with a lighter throttle spring but your unable to obtain the part without buying the whole throttle body and that's just ridiculous.
I remembered that Tokyo Mods sold lighter springs so I checked them, unfortunately they don't have one for the YZ's but they do have ones for the Honda's (same brand throttle body). Decided to buy one and see if it would work.
If you look at the pictures attached the spring on the right is the 2014 YZ spring and the one on the left is the Tokyo Mods Honda spring. All I did was bend it back a little bit and cut the new spring to match the stock 2014 YZ spring. Once that is done you just drop it in place of the existing spring and button it back up. Make sure your throttle works properly before putting everything back in place as I had a few issues with it not returning until I routed the cables correctly.
I know a lot of people have been looking at doing this mod so I figured I would share. This also worked on my fathers 2010 YZ 450.
Edited by MxSkater86, May 20, 2015 - 12:29 PM.