According to Factory Pro:

Factory Pro EVO Shift Kits . Replacement heavy-gauge detent spring . Completely changes the feel of your shifts . Same shifting effort, but gear engagement is quicker . Missed shifts virtually disappear . Used by many factory supported AMA and WERA riders

http://store02.prostores.com/servlet...ate=FactoryPro

Anyone use this? Sounds interesting.

 

I have theFactory ProEVO Shift star kit for my bike but havent had it installed yet, according to the people I have talked to who used them they love them, said it was a nice improvement. I also bought the Factory Pro Ignition Advancer kit too. I hope to have them both installed soon.

 

found it

http://store02.prostores.com/servlet...Detail?no=1171

sorry bout the repost
btw it is supposed to help with missed shifts before you need to start getting into expensive mechanical repair.