If you are looking for a red spring, I believe this is the same rate @ 475 lbs
A friend of mine called Cooter, see below , already put one on his SX 2014 he says it feels the same as the yellow spring.
https://www.ebay.com/itm/2008-10-Bue...EAAOSw1cNaJxXC
https://www.ebay.com/itm/08-Buell-11...VYJ12~&vxp=mtr