New Moto Guzzi Door Mats Available Now
Agree on the 'correct' TDC.On my old LM2, aside from the normal checks, there are letters visible; 'D' (Destra) Right and 'S' (Sinistra) Left through the inspection hole to the flywheel which show TDC, don't know if anything like this is available on newer models though?
The engine is not at TDC on the compression stroke. Rotate it one revolution and all should be well for the adjustment.
Normally, the operating clearance enlarges over time which is the reason for valve adjustments
The most important thing for a novice is if you have to adjust more than two to three thousands you most likely aren't on TDC.
I've been adjusting Guzzi valves since 1972. About 500,000 miles worth on 14 different bikes and have as yet to see a tight valve. I guess I could believe a valve seating deeper in the seat but there are so many other wear spots it more than makes up for that. Now I would say that for the last 10 years usually the intakes are very close to right and the exhausts are about two thousands loose the first check and the second check. After that there is virtually no adjustment needed. Now the first check is always a crap shoot because you have no idea how they did it at the factory the first time. The most important thing for a novice is if you have to adjust more than two to three thousands you most likely aren't on TDC.