And also keeps your bike's diaper rash at-bay!:biglaugh:
Seriously though, a good tip. I suggest using a turkey baster to pick-up the powder & then as a method of easy and uniform application. And for perhaps the ease of visualization, an ultra-violet bulb to highlight the powder, plus, for those of us of a certain age, it may trigger 'flashbacks.' And if the black-light doesn't do it, staring at the detail in this, may!
I have an original one of these I bought in San Francisco at Bill Graham's outlet store, decades-ago, one of the best investments I ever made. I paid $20 and now it's worth $800+ today. (2nd edition) I have a collection of posters, and I like to see the artwork, I keep them stored to keep the colors from fading. I have often thought of using some of this era's artwork on my faux tank.
This particular poster was first printed in late 1968, and re-printed just before the New Year, as it was a popular design. Remember, these used to be posted on storefronts, telephone poles, and the like, to advertise these artists' live concerts at places like the San Francisco Longshoremen's Hall, the Avalon Ballroom, the Fillmore (which became the Fillmore 'West' when another opened in NYC), and other venues.
For anyone interested in the history of these talented artists:
http://antiquesandthearts.com/2009-03-24__12-11-32.html&page=1
Once cleaned a dusting of talcum will help show exactly when it is leaking.