Just a heads up fro those tackling Jackshft bearing replacement. I followed the write up from Lakercr on Jackshaft bearing replacement. Overall a great help but for you Apex owners be careful not to lose the two bushings when you pull the shaft through the clutch side to get at the bearing. There are two spacer/bushings that mate with the back of the chaincase that fall off when you pull the shft out. Mine hung up on the top of the exhast gaurd and with some effort I think I goot them back on correctly. The attached link is the original but be careful not to lose those parts as they will end up in the belly pan without much effort............................just wish someone mentioned that little technicality.
http://www.totallyamaha.com/snowmobiles ... Track.html

http://www.totallyamaha.com/snowmobiles ... Track.html