Yes I feel like a dummy.
I managed to twist out the threads using a torque wrench and I am still not sure why.
I have the factory manual and it calls for 10 Ft/Lb of torque on the valve cover bolts but the threads let go at 9. My torque wrench is old but I have used it to build several engines including a CB700SC just 6 months ago. I think I will buy a new one as I now don't trust it.
Anyway, have any of you had this problem? Is it possible the manual is wrong? Let me know.
Now the fix. First the bad news is that the bolt screws into the cam holding block. You can't buy a replacement, it is a matched part of the head so you have to buy a replacement cylinder head! So the obvious thing to do is repair the threads with a helicoil kit. The second bad news is that the threads are an odd size. 7mm X 1. They do make helicoil repair kits but they are hard to find and expensive. After a long search on the internet I found a kit.
OK, after removing the cam block (you do not have to pull the cam chain tensioner) it can be repaired like this.
You need to have a good drill press with a vice or better yet a milling machine (which I happen to have). You need to clamp the block down tight but being very careful not to damage the surfaces. The hole must be drilled dead on or the bolt will not line up.
Here is a picture of the drilling operation.
Then without moving anything, take out the drill bit and install the tap in it's place. You can use the drill press or mill to start the helicoil tap so it will be dead streight. Just use a light feed while turning by hand. No power!!!
Then finish the tap in the normal way and install the coil using the included tool.
Mine is done and back together but if any of you need the 7X1 MM coil repair kit just PM me and I will send it to you free. It comes with 12 coils and I only needed one so I now consider it a community resource. Just send back what you don't use for the next person that needs it.