I have taken ownership a fleet of circa 1990 Yamaha quad bikes with air cooled 350cc single lung motors. Bikes had been sitting in a garage unused for 15+ years. Usage prior is unknown, as is the maintenance history. I had a local shop clean the carbs, adjust valves, replace all fluids, lube all things that take lube, replace all wear items, etc. All are running well now. Shop used no-name 10W40 Dino oil.
Machines will be used in all seasons in WI, so they will see a variety of temps (winters here can get down to -25F).
My question is should I consider switching to a synthetic oil? If so, what vis and flavor? So many people say no to switching to synthetic on older engines, but I thinking this is an old wives tale.
Thanks in advance.
Machines will be used in all seasons in WI, so they will see a variety of temps (winters here can get down to -25F).
My question is should I consider switching to a synthetic oil? If so, what vis and flavor? So many people say no to switching to synthetic on older engines, but I thinking this is an old wives tale.
Thanks in advance.
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