Yup , they are serviceable, there is a rubber & metal seal top & bottom to keep swarf out . They seem to be working ok . I’ll still use my needle greaser to put a bit more in there particularly between the rollers . Hanging the handlebar assembly from the ceiling w/rope allowed me to not disturb any wiring or cables A bit fiddly but not a bad job . Good for another 25k Mi. At least . As I haven’t had a bike with a conventional steering head in 20+ Yrs. That skill set was a bit rusty . Job done !