I learned about tri-flow riding bicycles...

I use the aerosol kind on the Valkyrie for stuff, including cable lube...

I got kind of stymied the first time I tried to lube my throttle cables till I asked around here (It was sort
of the same way Spoc noticed that Kahn was thinking "two dimensionally"...

)...
Anywho... I was told to protect the tank and loosen the handlebar clamp (the handlebars want to
swoop over and dent your tank if you don't take precautions) and slide the handlebars to the left.
Then there's enough slack in the throttle cables to easily get at the cable ends so you can put
lube down the casing. You're done when lube starts dripping out the bottom onto your
engine...
My throttle action went from awful (it actually stuck on at full lock) to great, has been that way for
a long time with no re-do... If you use WD or silicone spray, I bet a re-do would be needed pretty soon...
-Mike