There are two vacuum hoses coming out of the top of the carbs (black hoses). Looking from the back of the bike towards the front, the one on the left goes to the bottom connection on the petcock. The one coming from the right carb goes to the PAIR valve (used to help keep down emissions). The PAIR valve has a hose coming from the airbox and two that go to the top of the engine. The hose from the right carb goes to this valve as well. Remove those two hoses from the carb and connect the manometer to the two nipples (one on each carb) that the previous hoses were connected to.
Some people remove the PAIR valve, where in that case you would need to cap off the right carb vacuum line.
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fuel lines: 5/16 " ID (8mm) fuel line from auto parts store. Use regular line (more pliable) , not fuel injected type (rigid)
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Red is fuel line to the petcock
Blue is vacuum line to the petcock
Green is carb vent. Most people remove this and throw it away
Yellow is vacuum line for PAIR system (removed)
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That hose is a drain for the area around the filler cap.It doesn't have to be connected to anything. It just needs to positioned so any excess fuel can drip onto the ground.
NOTE: Some members have found this hose connected to the Carb Vent by previous owners. Although this configuration will function perfectly as a carb vent line when dry, when it rains or you wash your bike, this SERIOUSLY WRONG configuration also functions as a perfect gas cap well drain that empties directly into your carb vent tube and fills your carbs with water.
