Battery box mod for easier carb removal

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What does this do?

In this modification, you're making the airbox and battery box into two different parts, so you can pull the battery box out by itself. This gives you more room to move the airbox around and get at the carbs to remove and reinstall them. This will result in a quieter and closer to stock bike, as opposed to messing around with pod filters. This also makes carb removal faster by eliminating the chore of removing all the inner fender bolts to move the fender out of the way.

Some people don't have any trouble getting the carbs out in stock configuration. If this is true for you, there's no use wasting your time with this mod.

This is how much room you have between the airbox and carburetors once the battery box is removed and the airbox is slid toward the back of the bike.

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First, remove the airbox. If you removed the box from the rear of the bike all in one piece, you need to split it by removing all the bolts around the perimeter, unless you think you can cut off the battery box while it's still all in one piece. This is what you'll have once it's out:

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Next, you're going to cut off the battery box. In stock form, it is part of the airbox. When cutting, make sure that you don't cut into the airbox itself. Putting extra holes in the airbox will make your bike run too lean. This is bad. When you saw, it's easy to get away from a perfectly square cut and drift to one side or the other. If you can't get a straight cut, you should at least err toward the side of the battery box.

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Bolt the battery box back together.

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Reinstall everything. Keep in mind that you're removing a mounting point for the airbox, which is not a big deal, as everything still fits together tightly. The elongated holes in the bottom of the battery box allow room for fore/aft adjustment, so slide the battery box tight against the airbox, then snug up the bolts that go down through the bottom of the battery box.

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If it looks like there is too much space from the width of the saw you used, add some sort of shim, such as a double-thick cereal box. Things shouldn't move even without the shim but may vibrate slightly more.


One other thing you may want to consider at this time is putting hose clamps on the air box boots where they connect to the carburetors. The stock springs have only 2 modes - easy and PITA.

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