I have used anti siphon valves from fish tanks successfully on my cars. I worked in a fish store for a few years as a teenager and a customer recommended it to me one day. They are used on fish tank air pumps so that water will not come into the pump in the case on power failure. You can buy them at ant fish store you will need to find the right size tubing to connect to the bleeder though. I have not tried this on my v-rod but it worked great on my cars when I did not have a second person to help.