As some of you may know from following me on Facebook, Twitter, or Instagram, I am neck deep in a front-end rebuild of my 1972 Harley-Davidson Shovelhead FLH. I have completely disassembled both fork legs, methodically cleaned each internal part, and ordered the replacement parts necessary to put things back together.
Of course, when all is said and done, I am going to have to refill the front forks. Therefore, I thought I would share with everyone some Harley-Davidson fork oil specifications – in particular, information regarding the proper fork oil weight to use and capacities for major models.
Weight: As a default, use 20wt. You will want to consider 10wt and 30wt under more extreme conditions (riding-wise or temperature-wise).
Capacity by Model:
-Note that “wet” means you drained the fork leg from the drain plug and plan to refill, while dry means the fork leg has been completely disassembled for a rebuild. In the first case, there is a little residual oil left in the fork leg. In the second case, you are filling a fork leg that is bone dry (requiring a little more).
-Most Harley-Davidson models have a drain screw in the bottom. However, the only way to truly drain all the oil is to remove the leg from the triple tree and turn it upside down.
-If needed, but the conversion between ounces and mL is 1 oz = 29.5735 mL
-The quantities given are per fork slider. You will need to order twice the quantity listed in the table below to fill both fork legs.
-The table generally covers “earlier” model Harleys, as these are the ones I am more familiar with. If you have another Harley or even another make/model of motorcycle and need your specification, please feel free to reach out via the contact page. I have a ridiculous number of manuals, and I will try my best to help where I can.
|Sportster (up to 1972)||5.5||6.5|
|Sportster (1972 - 1983)||5.0||6.0|
|Sportster (1984 - 1987)||5.5||6.5|
|FL/FLH (1948 - Early 1977)||6.5||7.0|
|FL/FLH (Late 1977 - 1984)||7.75||8.5|
|FX/FXE (1973 - 1983)||5.0||6.0|
|FXR/FXRS (1985 - 1986)||6.0||7.0|
|FXWG/FXST (1980 - 1984)||9.0||10.2|
|FXWG/FXST (1985 - 1998)||10.2||11.2|
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