what weight of oil do i use for a honda 300 4 stroke

 

Some good basic oil info: http://www.thumperfaq.com/oil.htm

If I lived in the frozen north, I would run 5W30 in winter and 10W40 in summer.

In the milder southern states, I run 10W40 in winter and 15 or 20W50 in the hot summer months.

 

It should be spelled out in the owners manual. And if its an air cooled motor, be very careful about using oils which have a rating lower than 10w 40.
According to my service manual (300ex) it doesnt ever recommend, anything under a 10 weight rating, even for dead of winter riding. The lightest weight oil it recomends is 10w 40, with 20w 40 or 20w 50 for summer use.

 

Actually, the newer Honda owners manuals (for the same old quads they have been building for years) recommend 10W30 or 10W40. Then the chart has an arrow at the bottom with 5W30 running through the whole temperature range.

This is all a big change from the old Honda oil viscosity charts that we have been use to for years and years, yet the machines haven't changed. I have posted on this before, and nobody seems to know what is going on at Honda..........

 

I just run 10w 40 year round. I let em warm up for several minutes in the winter, before I ride.

 

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