I've seen them machined on a VCM out of 'blanks'. We actually have a manufacturer here in this little town. www.halibrand.com
what type of machine is it that they use for making rims for motorcycles like u see on tv?
I have seen that on TV as well, the one I saw was a Haas VF-4, a high performance Vertical Machining Center capable of rapid speeds of 1000ipm and a 4 second tool change time. These things are very impressive; essentially they are a typical vertical mill only fully enclosed. They also can hold tolerances in the .0001 - .0002 range.
the rims you saw were on american chopper I presume. I saw the black widow show and was surprised to see how they made the frames.
My estimation is that they turn on a large lathe or VTL a wheel blank with all the tire specific requirements (all the controus etc have standards which need to be met so the tire will seal to the rim). I suspect that those are pruchasd as I am sure they would have shown how the blanks were turned.
The blank may have been clamped into a manual indexing fixture. Basically it is a fixture which allows the blank to be manually indexed using pins. I suspect this was how they did it as I watched the guy run one onf the spokes complete before going on. Now that might have been done for TV to show how the pattern would look or maybe to see if the pattern was correct, but I suspect it was due to fixtureing. The ideal way would be to get a large machine with sufficient travel and run all the passes for each tool complete before tool changing as this would be the quickest.
Oh yse, the mill was a Haas mill probably a VF1? Not sure on the model but positive on the make.