[Vegas Street Rider]

You definitely need to replace the vacuum line as it regulates the amount of fuel your engine receives when it is running. It could create both lean and rich mixture conditions which could do damage in the long run.

Also, if you leave the petcock in Prime, you could get a situation where the fuel could seep through the carb and into the airbox. Not good.

The vacuum tube does run from the back of the fuel petcock to the carb just behind the throttle wheel on the top right side. If you turn the hand throttle just slightly, you will see a nipple behind that throttle wheel on the carb. Not able to post a pic at this time.

You can pick up some vacuum hose at any auto parts store along with some ring clips. Not sure on size. Probably 1/4" or 3/16" inside diameter. You will only need 6 inches or so. Hope this helps.