A brief comparison of two more modern carburetors
If you are interested in replacing your Bing or Mikuni carburetor with a different style, this is a review that might halp in your decision. Not strictly vintage , but could be considered a performance modification for your vintage bike. The real benefit should be increased fuel range on a tank of gas. I have used Lectrons in the past and have one mounted on the Penton 400.
Links to websites below.