back from Spa, and very tired.....
first impressions: guzzi, guzzi, guzzi.
never seen as much moto guzzis going that fast. weather, sunny, rainy, warm and cold.
back to my engine: there are two points i realized disassembling the engine. engine has a K2 head, cam chain sprocket seems to be from a F2, as both 7mm screws seem to be from a F2. i do have two versions of these 7mm screws: one pair is 11mm long, the other one is 12mm and is shouldered. in my engine i had the 12mm.
the camshaft does have axial play. you will find a position where the camshaft rotates free. pushing the camshaft to the other side,the thread of the screws touched the head and milled a very small amount of aluminium from the head (this spot can be seen near the round rubber sealing of cyl 2). this continuous load may have caused the failure.
second, my self made slots in the cam sprocket are a little bit too long, more than necessary. this puts unnecessary loads to the threads of the cam tab.
now i have shortened the 12mm screws, cause i will go for the shouldered ones.
4 pics from spa 2009
mec