I posted a few days ago about my mate's A10 where he hadn't tightened the camshaft gear properly causing too much end float on the cam so that one lobe was lifting two followers at the same time!! Anyway, whilst doing the job I had a 'light-bulb-moment' and stumbled across a quick way of removing and replacing the inner timing cover and resetting the valve timing. Normally, to set the valve timing, it is necessary to remove the dynamo drive sprocket (after removal of the inner timing cover) to liberate the intermediate timing gear, then line the marks up and replace the inner timing cover and then the dynamo sprocket with its cork spacer. Removing the dynamo drive sprocket is a bitch of a job because you need loads of heat and an aluminium drift to get it off the taper. So, I removed the inner timing cover with the dynamo drive sprocket and intermediate gear. After remedying the camshaft gear issue I reset the valve timing with a spare intermediate gear I have. I withdrew the spare intermediate gear and considered how likely it was the camshaft gear or crankshaft might move. The crankshaft gear isn't going to move - that's one hell of a lump of metal to shift! I felt the camshaft gear and, that too, seemed very unlikely to move. So I just replaced the inner timing cover with its intermediate gear and dynamo sprocket, just as it had come off. Obviously, you can't see the marks on the intermediate gear, but that doesn't matter because the intermediate gear's marks just ensure the relative positions of the cam and crank and don't line up every revolution. As you refit the inner timing cover you can feel the gear engage by gently 'jiggling' the dynamo sprocket. You can also see in the gap between the inner cover and the crankcase that the camshaft gear isn't moving. In fact I put the inner timing cover on and off a few times and rechecked with the spare gear and the gears showed no inclination to move away from their respective positions. As additional security you could lock the magneto with a bolt through the earth brush holder but I don't think this is necessary. If you have a spare intermediate gear, this is going to save a lot of time and hassle. I'm sure somebody has thought of this before because it's one of those 'blindingly obvious' things to do, but I haven't seen it on the forum.
