I am looking for the same information.
Yamaha outboards presently uses the last letter in the model number to determine the year model of the engine. Each letter of the alphabet represents a particular model year run.
1983
Yamaha outboards use the last letter in the model number to determine the year model. This letter is referenced to a model year chart to find the year of manufacture.
1988
find the VIN number on the engine or on the frame then run it through a dealer, or look it up online.
By the letter in the number
1984
You must determine the "g" number model of the cart
2004... the tenth digit tells you what year it is... there is a chart here http://forums.atvconnection.com/yamaha/315326-how-determine-model-year-yamaha-warrior-350cc.html
how do i find out year model on yamaha timberwolf
10th digit of VIN is always model year; use common sense to determine decade.
year and model yamaha vin 510203147