Year & Fuel / Oil Mix for 5HP Yamaha

[Roobarb]

I have just acquired a 5 HP 2-Stroke Yamaha and have no idea of it's age or what fuel / oil ratio to use.<br /><br />The serial number is 5BS 661 L 40414.<br /><br />I have used it with a 50:1 mixture but it sounds a bit rough. Should I be using 100:1 instead?<br /><br />Thanks in advance for any help.

 

[NathanY]

Re: Year & Fuel / Oil Mix for 5HP Yamaha

50:1 is correct. But without the model number I cant tell you the year. The rough idle is probably due to a carb problem, you might be running a little rich.

 

[Bear]

Re: Year & Fuel / Oil Mix for 5HP Yamaha

5BS 661 = 1973-1980