Locate the transmission fluid fill hole. On a 2002 Sportster, the fill hole is located on the left side of the transmission, just below the clutch cable adjustment screw.
Remove the transmission fluid fill plug.
Use a 3/8-inch wrench to loosen and remove the transmission fluid fill plug.
Insert a funnel into the transmission fluid fill hole.
Pour the new transmission fluid into the motorcycle. Slowly add transmission fluid until it starts to overflow from the fill hole.
Replace the transmission fluid fill plug.
Use the 3/8-inch wrench to replace the fill plug.
Check the transmission fluid level.
The transmission fluid level should be checked with the motorcycle in an upright position. The fluid level should be between the "full" and "add" marks on the transmission oil dipstick.
Add additional transmission fluid if necessary.
If the transmission fluid level is low, add additional fluid until the level reaches the "full" mark on the dipstick.
