I have an '07 Ultra with a Lehman trike conversion. I was always told that the primary was filled with oil to the bottom of the derby cover hole while the bike was sitting upright and level. That requires more oil than what the owners manual says. Does anyone know what it should be? My trike is obviously upright and level all the time. Don't really want to run it low or too high and I understand the consequences of it being too low but what could get hurt by running it too full? Do I go by tried and true for the oil level or by the manual?

 

Primary fluid level is checked with the bike vertical. Harley has "waffled" with their recommended level between 32oz's and 38oz's. The level should be set to the bottom of the metal on the clutch basket. I have always added 1 qt after a drain and refill with improved shift engagement and neutral find and no mechanical issues. I do not use synthetic oil in my primary.

 

It's not exact as long as the clutch is sitting in the oil a little it's good. The oil should just cover the bottom of the clutches about a 1/2 inch maybe. If you over fill it can cause it to slip. Under full can cause the bike to pull at a stop.