what is the difference between 04-05 & 06-up thumb throttle covers?

[Black R/T]

like the title says, what is different? also, did they change the spring in it?

[blacknblue#2]

the whole throttle assembly on the bars is defferent. the 06+ has a TPS (throttle position sensor) on the handlebars where the 04/05 dont. correct me if im wrong