Trying to identify exact year of my motor for timing purposes. The fellow I bought the trike from gave me paper work on the trike. He said it was a Brazil Type 1 1584 cc dual port motor. The numbers on the paperwork stated the number on the case as BB180113. He said it was between a 69 and 74 model. I looked up case numbers and I can't find one with two BB's, just one and it would be from july 69 to july 70. Anybody know what these numbers would tell me. Thanks