front sprocket.....question

[xparallax]

hey folks been awhile since I was on this site.......last night I pulled my front sprocket off my klr cause I think that I have a output shaft seal leaking...can I remove and replace this seal easily? w/ puller etc.I also noticed that the sprocket has rubber extruded through the holes in it is this rubber seal nessesary to keep the output shaft from leaking? ( mine is no good anymore is falling apart)...any infogreatly appreciated...< I am to damn cheap to buy a manual>..........jimmy....eugene,oregon.......