Hey guys I'm looking to get some new sprockets for my F4. A couple quick questions though.. Are all sprockets model/brand specific for bikes or would an F3,RR,F4i, ect fit an F4?

Also my rear sprocket I want to get 43 (-2) since most of my riding is interstate and I don't really need the high rpm's. I know this is unnatural but I was curious if anyone else has tried this setup? If so, how did/does it work for you?

Thanks a lot and ride safe..