Al, As a precaution I would remove the sump plate and clean the filter gauze, also check the little ball valve is free to move. Remove the oil tank and oil lines, clean and blow through. Be careful to reconnect the pipes correctly, the crankcase is marked F...Flow and R ....Return. Refill with the correct recommended quantity of fresh oil. Reading your first post would indicate to me that the scavenge side of the oil system is not working properly, or that the system is overfull. The first sign of this is a smoky exhaust, and oil being dumped through the breather. When running, the oil level in the tank should stay the same, or even rise slightly as the pump returns oil which accumulates in the engine sump. As mentioned, the dynamo chain is tensioned by slackening the dynamo strap and rotating the body. Pull the dynamo towards you to trap the cork sealing washer between the inner timing cover and dynamo, replace the grease as this is the only lubrication the chain gets.
Swarfy.