OK so i have a 2000 model 748 with the 3 spoke wheels on it. I have bought a set of 5 spoke marchesini wheels for it from a fila bike so the front wheel is red and the rear is purple. I am looking at getting them painted but after opinions on what colour. Just as a further point I am not a purist so I'm not worried about it being an original colour. I have seen a 996 with very bright gold wheels which I quite liked but still unsure. Feel free to post pics of your own so I can see how they look.
Photoshop could be your friend. It's very easy to change colours in an image. You can try a few options virtually before you make a decision.
Look at a RAL colour chart for rough ideas. RAL colours are those used by powdercoaters most often. As mentioned try photoshopping or just go to a powdercoaters, or if you are contemplating wet spraying, then a motorfactors and look at colour chips. http://www.ralcolor.com/ You could try these people below they have done a number of wheels for me including some Yamaha RD250LC wheels which are black with polished rims. They also do trick metallic finishes. Maldon Shot Blasting & Powder Coating Ltd
Black. I like black wheels, they look good and most importantly don't show the dirt and particularly chain lube, a friend had an early 900SS with the white frame and wheels, it was a nightmare to keep the rear wheel clean. Both my Ducatis have black wheels and if I had a choice I would always have black wheels on a bike, my Guzzi has silver wheels because that's how it came, as it's a shaft drive the chain lube mess doesn't happen so I can cope...
Definitely liking the gold a lot. Will be going and talking to the spray painter when I'm back in Perth next week.