About the 'choke,' it's an enrichener. Yes, more fuel is introduced to the engine. A traditional choke is a simple plate blocking-off the air inlet to varying degrees, according to its position. The same amount of fuel is presented to the engine, but the amount of
air is less, causing an enriched mixture to the engine. The VMax works by supplying more fuel, the CV carb slides still flow the same amount of air.
Recently one of the members discovered their enrichener plungers weren't synchronized. They weren't allowing the same amount of additional fuel to enter the fuel venturi pathway. A good cleaning of the brass plungers, lubrication, and carefully ensuring that the rods and lever system opening and closing the enrichener pistons was functioning properly was needed. See the pic:
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If you own a VMax, either you pay-attention to the condition of the fuel delivery system, or you have problems. A clean gas tank, meaning no rust, and unobstructed pilot jets in the jet block will allow you to have a decently-performing bike which idles properly, doesn't have any low-speed issues, is easy to synchronize the carburetors, and which operates as it is supposed to behave.
Over time, certain gremlins arise. Intake leak(s) can come from a variety of places. The points of connection of the airbox to the carburetor bellmouths, the lower carburetor bodies' attachment to the VBoost manifold, and the VBoost manifold's O-rings to the cylinder heads are all places where air infiltration can cause you to pull-out your hair until you discover that/those leak(s).
Other likely places for leaks are deteriorated fuel lines. Say you bought a 1988 VMax, and you're having issues. Think about the age of the bike, and whatever service it has, or
hasn't-had. The molded T-line to service the carburetor bank is original to the bike, most-likely. It's 33 years-old! As are the other rubber components, including the CV carburetor diaphragms. The gas tank is rusty. Fine particulate material from that rusty tank is plugging your pilot jets, and that's what when you have the bike idling, one or more of the pilot jets has become obstructed by sediment/rust particles. Sure, try the 'peashooter,' try the 'shotgun,' or go straight for the cure: pull the carburetors, split them into-two, and remove the float bowls, remove the jet blocks, and then remove the gas delivery jets, and clean the jets and their passages. You want to be able to see light at the end of the jets' tunnels! The carburetor bodies also need to be cleaned, for this purpose, an ultrasonic tank is what I consider to be the best way to do this.
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While the carbs are apart, check for proper fuel level, you can use the carb body casting behind the float for a rough starting point, but a 'wet-check' will allow the best fuel delivery and best gas economy. If I open the carbs on a new to me bike, the float needles with their Viton-rubber tips are replaced, and the brass seat they go-to is cleaned.
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Have new jet block gaskets on-hand for the tear-down, because they inevitably tear when you try to remove the jet blocks.
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About splitting the carburetors into two banks: to do this, you need to work around the molded-rubber T-line, and don't be surprised if your 33 year-old rubbers fall-apart. Thank Yamaha for still allowing us access to as-many parts as they do for our bikes, because when they decide to stop supporting the replacement parts, the value of your bike is going to plummet. Some parts are now unavailable, but thankfully there is a cottage industry of what the UK members know as 'breakers:' people who part-out the bikes. They will be the resource of last-refuge when the lack of OEM, new parts happens.
Currently there are suppliers of the rubber donuts used for the carb joints and the CV slide diaphragms. Surface cracks on the rubber donuts which don't leak air will still provide proper air levels. use the old method of spraying something like starting ether, carb cleaner or another aromatic hydrocarbon on the boots or the cyl. head-VBoost joints, and listen for the increase in rpm's, a sign you have located a leak. Don't stop at that one leak, continue to search for more. In the case of an O-ring leaking at the VBoost to cyl head point, replace all four of the O-rings since it's apart. it is likely that disturbing the seal all four O-rings have will cause the others to leak, so replace them-all.
These tips are based on my work on these bikes for nearly 30 years, they represent issues I've dealt-with on multiple VMaxes. Remember that no-matter how-well that you clean all the parts in that set of carburetors, replacing anything which could be causing an air leak, or removing deposits which plugged-solid your pilot jets, if your gas tank isn't shiny-clean inside, you're just going to soon find your pilot jets are plugged again as an uneven idle, cold exhaust header(s) at idle, and poor throttle response off-idle happen again because of rust in the gas tank. Removal of the gas tank isn't difficult, follow Buster's how-to, and if you decide to use a kit to line the gas tank, follow the directions
exactly or end-up with more problems than you began-with. Heed the input of the specialists on-here, who work on these for a living, people like Sean Morley,
danymax for the carburetors,
Captain Kyle and Damian, they are the subject matter experts whose experience and knowledge collectively have see anything you're experiencing with your ride. Here's an example of something I had happen, the bike ran, but was obviously not running properly, and fortunately, the position of the cam when it happened was not on the lobe, so there was no piston-to-valve interference, which would have been a much more-involved repair.
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Once you've dealt with your issues, and solved them, put your experiences here so we all can see what worked for you. You will be helping the next fellow with a similar issue or issues.
, when your young your legs are worth less than the bike 
