I had cleaned my carbs in an ultrasonic cleaner, reassembled them, and installed them. I ended-up with an uneven idle, despite adjusting the air mix screw under the CV diaphragm caps, and balancing the carbs. Spraying some starting fluid on the cyl. head to VBoost manifold area, using the tiny red spray nozzle wand resulted in a quickening idle, when I directed the spray at the bottom of the VBoost casting, and the cyl. head joint. It happened on the two front cylinders, #1 and #3.
I ordered the o-rings, you need four. See the pics for the part #.
Remove the left air scoop. Remove the plastic trays that the relays are attached-to. Wire them out of the way. You now have access to the throttle cable junction box, where you need to detach the upper and lower throttle cables. Don't lose the small screws or the parts.
I removed the airbox, the carb float bowl hoses attached in pairs to the sides of the airbox, I removed the gas line to the carb rack. Using either a long pry bar, or a suitable piece of wood (I used my wood-shaft ball pein hammer) to pry upwards on the bottom of the carbs, on each side (L-R) after opening-up the carb to rubber donut clamps about 1/2 inch, the carbs were now loose. I had removed the carb cables at the junction box by the left scoop. Now the carbs can come-out the left side of the frame. Set them aside, they have gas in the bowls, be-careful about where you place them, and remember that gas vapors can travel many feet, and can ignite, and follow the vapor trail back to the source of the gas, your carb float bowls.
The VBoost manifold is secured to the cyl heads by two allen-head screws for each cylinder. Use a wadded-up paper towel in each passage of the VBoost manifold, so anything you drop won't go into the cyl head inlet passageway. Loosen and remove the eight allen head screws, and take-notice that the #1 cylinder has a silver screw whereas all the other screws (with one other exception) are black-phosphor coated, and longer than the silver allen-head screw. The other short silver allen-head screw on the VBoost manifold is the outermost screw for cylinder #4. These two screws each hit an oil passage. If you look carefully you will see some sealant on those screws, where the other screws don't have sealant.
OK, your eight screws are all-out? Carefully lift off the cyl heads the entire VBoost manifold with all cables & etc still attached. It will come-out the left side, like the carbs did. Use a piece of baling wire to wire-up the VBoost manifold so the underside is now exposed, and the o-rings in their grooves are visible.
Stuff more paper towels into the cyl head intake passages. Now you're protected from dropping anything into the engine intake passages.
Use clean paper towels and some carb cleaner to clean the VBoost o-ring grooves, once you use a pick, to remove each o-ring. Also clean the entire machined surface of the cyl heads where the VBoost manifold sits when assembled. Do the same for the VBoost mating surfaces to the cyl heads. Notice that you will see some sealant smeared around the two holes where those silver screws go. That's to keep the engine oil in the engine.
I use a bit of vaseline smeared onto the o-rings to hold them in-place in their VBoost underside grooves. You don't need much. Also put a daub of sealant on the area around the hole where the two silver screws for the VBoost manifold are. Again, you don't need much at-all. Make sure the sealant is all the way-around the holes where the silver allen head screws are. Check and ensure that the o-rings are properly in their grooves.
Now, replace the VBoost manifold, onto the cyl heads, being careful to not lose the o-rings. Take the silver allen head screw for the #1 cylinder and put a bit of sealant on the threads, use it sparingly, on the lower-half of the screw. The top half of the screw will be through the VBoost casting, and that doesn't need any sealant. Now do the same for the #4 cylinder and VBoost manifold, where the other silver screw holding down the VBoost to the cyl head. Do not fully-tighten these screws!
Now insert the other allen head screws (the black-phosphor ones) into their respective locations on either side of the other VBoost passages. Once all the screws are in-place, snug-up the screws, bit by bit, until you have them snug. You can refer to the factory service manual for the torque settings.
Replace the carbs onto the rubber boots on the top of the VBoost manifold. Use a pry bar to carefully lever into-place the carbs so they 'pop' into the rubber donuts. They should be fully-seated. I usually use the frame on the opposite side of the bike above the carb rack to lever-against the carbs, make sure you are putting the pressure on a solid part of the carbs and not on one of the round open mouths for the air passage. Done incorrectly, you could crack a carb body.
Re-attach the carb throttle cables at the junction block. Make sure you are attaching them correctly. The translucent cover of the junction box labels them. When they're properly-connected, the throttle should work with no hang-ups, it should quickly snap-closed after turning the throttle all the way open, and then releasing the throttle. If you have the throttle hanging-up try putting a bit more slack into the adjustable throttle by the hand throttle at the handlebars. That will probably allow the throttle to snap-closed when you release the throttle from wide-open. Don't forget to take-up any slack at the throttle cable thumbscrew by the throttle housing.
Reinstall the gas line, the airbox, and the carb gas bowl vent hoses which attach in pairs on either side of the airbox horn, with the opposite ends attached to the pipes coming-out the tops of the float bowls before you replace the airbox. Don't forget the hose on the bottom rear of the airbox. Yes, it'a a pain in the butt.
You need to replace the plastic pieces that hold all the electrical relays under the left VMax scoop. Then install the VMax scoop. Make sure before you start the engine that the throttle is operating correctly.
I ordered the o-rings, you need four. See the pics for the part #.
Remove the left air scoop. Remove the plastic trays that the relays are attached-to. Wire them out of the way. You now have access to the throttle cable junction box, where you need to detach the upper and lower throttle cables. Don't lose the small screws or the parts.
I removed the airbox, the carb float bowl hoses attached in pairs to the sides of the airbox, I removed the gas line to the carb rack. Using either a long pry bar, or a suitable piece of wood (I used my wood-shaft ball pein hammer) to pry upwards on the bottom of the carbs, on each side (L-R) after opening-up the carb to rubber donut clamps about 1/2 inch, the carbs were now loose. I had removed the carb cables at the junction box by the left scoop. Now the carbs can come-out the left side of the frame. Set them aside, they have gas in the bowls, be-careful about where you place them, and remember that gas vapors can travel many feet, and can ignite, and follow the vapor trail back to the source of the gas, your carb float bowls.
The VBoost manifold is secured to the cyl heads by two allen-head screws for each cylinder. Use a wadded-up paper towel in each passage of the VBoost manifold, so anything you drop won't go into the cyl head inlet passageway. Loosen and remove the eight allen head screws, and take-notice that the #1 cylinder has a silver screw whereas all the other screws (with one other exception) are black-phosphor coated, and longer than the silver allen-head screw. The other short silver allen-head screw on the VBoost manifold is the outermost screw for cylinder #4. These two screws each hit an oil passage. If you look carefully you will see some sealant on those screws, where the other screws don't have sealant.
OK, your eight screws are all-out? Carefully lift off the cyl heads the entire VBoost manifold with all cables & etc still attached. It will come-out the left side, like the carbs did. Use a piece of baling wire to wire-up the VBoost manifold so the underside is now exposed, and the o-rings in their grooves are visible.
Stuff more paper towels into the cyl head intake passages. Now you're protected from dropping anything into the engine intake passages.
Use clean paper towels and some carb cleaner to clean the VBoost o-ring grooves, once you use a pick, to remove each o-ring. Also clean the entire machined surface of the cyl heads where the VBoost manifold sits when assembled. Do the same for the VBoost mating surfaces to the cyl heads. Notice that you will see some sealant smeared around the two holes where those silver screws go. That's to keep the engine oil in the engine.
I use a bit of vaseline smeared onto the o-rings to hold them in-place in their VBoost underside grooves. You don't need much. Also put a daub of sealant on the area around the hole where the two silver screws for the VBoost manifold are. Again, you don't need much at-all. Make sure the sealant is all the way-around the holes where the silver allen head screws are. Check and ensure that the o-rings are properly in their grooves.
Now, replace the VBoost manifold, onto the cyl heads, being careful to not lose the o-rings. Take the silver allen head screw for the #1 cylinder and put a bit of sealant on the threads, use it sparingly, on the lower-half of the screw. The top half of the screw will be through the VBoost casting, and that doesn't need any sealant. Now do the same for the #4 cylinder and VBoost manifold, where the other silver screw holding down the VBoost to the cyl head. Do not fully-tighten these screws!
Now insert the other allen head screws (the black-phosphor ones) into their respective locations on either side of the other VBoost passages. Once all the screws are in-place, snug-up the screws, bit by bit, until you have them snug. You can refer to the factory service manual for the torque settings.
Replace the carbs onto the rubber boots on the top of the VBoost manifold. Use a pry bar to carefully lever into-place the carbs so they 'pop' into the rubber donuts. They should be fully-seated. I usually use the frame on the opposite side of the bike above the carb rack to lever-against the carbs, make sure you are putting the pressure on a solid part of the carbs and not on one of the round open mouths for the air passage. Done incorrectly, you could crack a carb body.
Re-attach the carb throttle cables at the junction block. Make sure you are attaching them correctly. The translucent cover of the junction box labels them. When they're properly-connected, the throttle should work with no hang-ups, it should quickly snap-closed after turning the throttle all the way open, and then releasing the throttle. If you have the throttle hanging-up try putting a bit more slack into the adjustable throttle by the hand throttle at the handlebars. That will probably allow the throttle to snap-closed when you release the throttle from wide-open. Don't forget to take-up any slack at the throttle cable thumbscrew by the throttle housing.
Reinstall the gas line, the airbox, and the carb gas bowl vent hoses which attach in pairs on either side of the airbox horn, with the opposite ends attached to the pipes coming-out the tops of the float bowls before you replace the airbox. Don't forget the hose on the bottom rear of the airbox. Yes, it'a a pain in the butt.
You need to replace the plastic pieces that hold all the electrical relays under the left VMax scoop. Then install the VMax scoop. Make sure before you start the engine that the throttle is operating correctly.
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