Hy Guys,
when I bought my KX5 I found out, the motor didn't get a topend service since 1988.
So the carbon built-ups on the two drum valves forced them to seize in their bores and the steel teeths on the rack shear off the aluminum teeth on the drum valves. I didn't know that when I bought the bike.
3 teeths are gone from one valve, 4 from the other. I will try to describe the former location from these teeths: When you look at the valves from down under (you see the short shaft and then the teeths) you see this shorter teeth. When you give him the number "1" and count further in left direction "against clockwise direction, the numbers 2,3 and 4 are gone from one valve, 7,8,9 and 10 from the other valve.
How many degrees the valves will turn "at work"? Is it possible to use the former right valve, 180? turned, in the left bore and the former left in right bore without lost of synchronisation at work?
Two pics, poor quality: