anyone had experience with this? more specifically a coloured burst on a maple cap with a dark wood below, what do you guys do?

Depends on the dark wood. With any dark wood, if you want it to show, you may want to do the burst, and wai to finish the darker wood until you are spaying clear. You also have the option of color enhancement while doing the burst, such as a cherry burst when having a Mahogany back, or Tobacco burst when having a walnut back. The burst outer shade can be used to enhance the coloring of the darker wood, such as is done on some Les Pauls.

Depends on the dark wood. With any dark wood, if you want it to show, you may want to do the burst, and wai to finish the darker wood until you are spaying clear. You also have the option of color enhancement while doing the burst, such as a cherry burst when having a Mahogany back, or Tobacco burst when having a walnut back. The burst outer shade can be used to enhance the coloring of the darker wood, such as is done on some Les Pauls.

do you have any pictures of what you mean by this?

You asked for it you got it;) ...LOL Cherry burst LP with the red over the mahogany

looks nice, im actually looking at a greenbursted guilt maple, ala major metals sadowsky, im thinking about having heart rimu (ill be living in new zealand so supply is no problem) for the back but not too sure how it will work together, as ill want a contoured body so binding is out of the picture...

careful taping willkeep the stain off the Rimu, so you can stain the maple, and then clear coat the whole instument, just remember to seal the stain before clear coating, so you dont get too much color bleed. if you seal the stain properly, you will only get some tinted bleed at the seam of the maple and Rimu, and with a good number of clear coats, it will be completely unnoticeable.
Good Luck

i wont be doing it, im going to be telling one of our talkbass luthiers what to do :)

the colour im looking at
http://i34.photobucket.com/albums/d118/MajorMetal/Greenburst2.jpg

Yep, My FAVORITE color......I have one I built for myself a loooooong time ago in a trans green(no burst though), that i am refinshing and re dying. After 20 years the green got a little faded, and since it's my number 1, I decided it needed to be freshened up. Good Choice

i like how it fades into black, looks much classier to me, maybe ill even get him to put the black burst round the rimu to, make it even