On the honda parts micro fiche it shows only 1 dowel pin for each cam retainer. http://www.ronniesmailorder.com/fiche/modelframe.jsp?makeId=17&oModelID=2419 check under the cyclinder head part number 21 But on your guide on how to shim your valves it shows 2 dowel pins in your picture. http://users.rcn.com/lgarrido/Valve%20Adjustment/Adjustment%20010.jpg I checked my valves this morning before riding and they were perfect. After riding 15 laps or so I stop for a break. 15 minutes later I start bike up with one kick. Bike idles for about a minute while I put on my helmet. Then I here a small knocking sound 3 times and bike stalls. Kick starter will not move. So I bring the bike home and start to take the cyclinder off. As I loosen up the cam retainer bolts I notice that the bike will now turn over. Valves are fine. Piston and cyclinder are fine. All cam bearings are fine. &%$#@! are my cam retainers missing a dowel or not.