Hi! I'm trying to decide the best method to use for a groom's cake. He wants a 2-D shaped cake to look like his motorcycle; I was thinking FBCT (or maybe chocolate transfer, but it's the entire top of the cake) is probably what I'll end up doing. My concern, though, is that it's a black motorcycle with black seats, on a dark chocolate background.
Any suggestions on how to get clear definition between the black seats and black body? Also, can I use piping gel or corn syrup (or something else) over the FBCT after it's placed on the cake, to make the black body parts shiny? 
Thanks in advance!

here's a thought--have you ever used candy clay or fondant? you can paint it on to get definition using a combination of gum arabic and water--the edible glitter flakes are gum arabic, check the label--they dissolve in water--purchase at michael's, hobby lobby--looks like patent leather or a high gloss finish on a bike--you could do this with the buttercream too--and handling any of it cold or frozen keeps it from stretching too much for yah and cutting it nice & thick & chunky helps too

and you can ice over the chocolate iced cake with a lighter color for a better contrast too--either all over or just where the bike will sit on top--

also to get definition you can outline the bike in another color--