The question of the purpose of the slotted lower front engine mounting has set me thinking and perhaps I have come up with a solution. As most owners will be aware, after removal of the inlet and exhaust manifold locking rings, it is possible to remove the rear cylinder barrel without the need to remove the engine. However, it is not possible to remove the front cylinder barrel due to there being insufficient space between the cylinder head and the front downtube of the frame. Is it possible that, with the removal of the upper front mounting bolt, the slot would also permit removal of the front cylinder barrel without the need for removal of the engine? Slackening the lower bolt and both bolts of the rear mounting would permit the engine to be moved rearwards to the extent of the slot. Would this then provide sufficient room for removal of the front barrel? I will investigate this further in the next couple of weeks as I install the engine in my current restoration.
