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Join Date: Nov 2007
Location: Chandler, Arizona
First of all, you need to remove the tank, and have a good flashlight. There are 4 rubber connectors, 2 elbows that go between the carbs and the heads, and two ducts that go between the carbs and airbox. All 4 of these are different. it is important to know where each one goes. First, remove both air filter housings. They prevent the airbox from being moved up. Then wrap something around the bottom of the airbox and around the frame to hold it up. Otherwise it will try to drop when you remove the ducts between the carbs and airbox. The ducts are a bit difficult to get out of the airbox. Squeeze them a round a bit, and spray plenty of WD-40 around where they fit into the airbox. Make sure they are not stuck. You will have to flatten them out a little with your hands to get them out of the airbox. The WD-40 helps a lot. It makes them really slippery. Do not remove the throttle cables. once you have the carb to airbox ducts removed, make sure the airbox is as high as you can get it and is held tightly inn place, This gives you room above the carbs to work. Next, remove the carburetors. Leave the rubber elbow attached to the front cylinder head, and the rear rubber elbow attached to the rear carburetor. Once everything is loose, spray some WD-40 on everything, then wiggle the carburetor assembly out from the right side, then remove the cables. It may seem like the carburetors won't fit through the opening on the right side, but they will. They just have to be oriented correctly and they come right out.
Now, take a look at the Rubber ducts that go between the carburetors and the airbox. You will notice there is some extra rubber around the top, where the ducts connect to the airbox, and it is very stiff. Notice that there is a groove in the ducts. This groove fits in the airbox, and holds the duct in place. The bottom edge has to be outside the airbox, the inside has to be inside the airbox. It fits kind of like a rubber grommet. The hardest part of putting everything back together if making the ducts fit back in the holes in the bottom of the airbox. The problem is the really stiff rubber at the top of the ducts. I took a box cutter knife, and VERY CAREFULLY trimmed off some of this rubber, to make the duct a lot more flexible. DO NOT get too close to the groove. With some of that rubber cut off, the duct will be a lot more flexible. You can usually pop them in with your fingers, but if not, use a piece of 1/4" wood dowel rod with the rough edges sanded down. DO NOT use a screwdriver. That rubber is real easy to poke a hole in. That mistake cost me $65 once. Once the ducts are snapped in all the way around, you can tell by looking at them whether they are seated properly. The bottom ridge of the groove should be even all the way around, and the duct should turn in the airbox. The fit between the airbox and the groove in the rubber ducts is what seals them. I did this mod at about 30,000 miles on my '02, and it lasted to 108,000 when a cam chain broke. You need to make sure that all the rubber ducts and elbows are in the right place and oriented properly. They have little rubber tabs on them to help align them. This is not a fast job, but it does not have to be difficult. Everything does fit. If it doesn't there is a reason. Just use plenty of WD-40, and all the rubber parts will go together easily. It's kind of like mounting a tire. To me that is an easy job, but there are those that just don't seem to get it. I have replaced a lot of rear tires on Vulcan 750s, and never had any problems. Others will tell you that you have to have a tire mounting machine.
I am a motorcyclist, NOT a biker.
1997 Vulcan 750, purchased about a week ago
2006 Sportster 1200 Low
2013 Royal Enfield Bullet 500, converted to carb
2001 Yamaha XT225, heavily modified
2004 Honda Rebel 250
1979 Vespa P200E
2002 Vulcan 750 parts bike
1994 Yamaha XT225 parts bike