I have a 87 zilla. I know the carb isn't stock, and was wondering what size carb it had? If anyone can tell me how to figure this out, I would appriciate it. The carb looks like the 44mm Mikuni Trinity offers for the stage 4 zilla kit. The motor has a stage 4 port job and a o-ringed head so I was wondering if it has the carb as well.

 

Take a metric ruler and measure the inside diameter (ID) of the front of the carb bore. Not the back where the air box boot mounts, but the front where it goes into the intake. The inside diameter is the size. If you look on the side, you should find some letters such as VM, TM, TMX, etc. THis is the carb model.