Question about 2006 Harley Davidson FLHR Road king

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If I use synthetic in my primary how often should it be changed?

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You may want to follow the standard changing intervals just so it is easier. With synthetic oils you will benefit from better lubrication, cooler temperatures, longer transmission life, and if you desire longer intervals between changes. You could just change as needed shorter intervals city driving and much longer intervals highway driving , much like motor oil. Or set a longer interval to follow for the transmission change. The manufacturer usually gives you recommendations in the owners manual , unless you keep a chart it is just easier to follow that recommendation. Besides, oil is cheap compared to your bike. More changes are always better than less changes.

Posted on Sep 16, 2010


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If changing your filter as well as the oil, your bike should take three quarts of oil as best as I know. Always check your oil using the dipstick when you change it. Change the oil and filter and add three quarts, start the engine and run it just a bit, two or three minutes. Check the oil level with the dipstick. The dipstick has two marks on it. The upper mark is 'FULL HOT" while the lower mark is 'FULL COLD'. Make sure your oil level is between the two marks and never overfill.

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