mavgrab302
Well-Known Member
If your looking at that diagram the right side of picture is the top of carb. Do lvlheads shotgun (also easily googled) and just go from there.
Giving up on Vmax
- Thread starter Seve Moreno
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mavgrab302
Well-Known Member
If you piece together what i have given you you should be able to figure it all out. Id take the carbs out (i knowa pain in the ass) i had to have had mine out 10 times getting mine to run right but when i finally dailed it all in I never had to touch it again and that was 30,000 miles before i sold it. Here is link to level heads also informative as is the dynajet. https://vmax.lvlhead.com/tips/shotgun.htm
2017VMax
Well-Known Member
A black, feathery carbon deposit on your spark plugs can be an indication of a weak spark or an overly rich fuel mixture. Causes may include a stuck choke, misadjusted or heavy carburetor float, a leaky injector or carburetor needle valve, low coil output or high resistance in your spark plug wires. A dead oxygen sensor or coolant sensor also can be a cause of carbon fouling.
A heavier, oily black deposit means that oil is being sucked down into the combustion chamber, likely via worn valve guides, guide seals or piston rings or a cracked piston. Check for oil consumption problems including leaky valve cover gaskets, crankshaft end seals and oil pan gaskets. Tightening your automobile’s valve cover or pan bolts may prove a temporary fix, but you’ll likely need to replace the gasket.
https://e3sparkplugs.com/blog/are-your-spark-plugs-trying-to-tell-you-something/
A heavier, oily black deposit means that oil is being sucked down into the combustion chamber, likely via worn valve guides, guide seals or piston rings or a cracked piston. Check for oil consumption problems including leaky valve cover gaskets, crankshaft end seals and oil pan gaskets. Tightening your automobile’s valve cover or pan bolts may prove a temporary fix, but you’ll likely need to replace the gasket.
https://e3sparkplugs.com/blog/are-your-spark-plugs-trying-to-tell-you-something/
desert_max
Well-Known Member
Automotive quote straight off the interweb? Only partially relevant. Most of what the OP needs is motorcycle (Vmax specific).
Seve Moreno
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So I'm looking at my pilot jet and 3 of the 4 were falling out. Only one was screwed in and it was all the way down. Is there some way to prevent it from backing out. And what's the stock number of turns for the pilot jet?
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mavgrab302
Well-Known Member
See something simple. Someone had to have had those apart before and forgot to tighten them. Lol. Now to make sure are you talking about the a/f screw on the outside of carb or a pilot jet? The pilot jets are internal and seat down all the way. The air/fuel screws adjustable from out side are different. If your talking about those screw them in all the way, gentle seat them so you dont mess the tips up. I’d start at 3 1/2 turns out and go from there.
Seve Moreno
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I'm talking about the jet inside holder with the rubber plug you have to remove to get to the jet. Not the a/f screw.
Yeah, those shouldn't be backing-out. Someone didn't screw them in, or if they did, they didn't snug them.
mavgrab302
Well-Known Member
Yeah i was just making sure. That pretty much proves someone has been in those carbs because seated jets dont backout unless loosened. What exhaust fo you have? I ask because if i were you Id go ahead and buy stage one kit or if morleys still sells his get that being theyre off. Unless it already has one, then id start off from what i wrote earlier in this thread where i listed jets, needle position, a/f turns etc.
Seve Moreno
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Everything is stock on the bike. I was looking at the needle and it had a small washer and what looked like a plastic spacer. does anyone know if both of these are stock for the needle?
Not good advice! The Dynojet Stage 1 kit will-not be a good investment. There are multiple threads on-here about buyers having problems getting their bikes to run properly. The DJ Stage 7 kit will be a better choice if you are looking for a re-jet. Yes the Morley's Muscle jet kit is another choice. Not sure if Factory Pro is still available, they were another vendor of VMax jet kits. I run a DJ Stage 7 and I retain my VBoost, which makes it simple to balance the carbs with a Motion Pro 4-tube carb synch tool, or a bourdon tube 4-gauge set, I have both.
If you buy Sean's kit, you get Sean's assistance to get it installed and running correctly. That's a huge advantage for the owner who has already-found that a simple thing like a CV downdraft carburetor set from a VMax is a mystifying thing to most shops. [email protected]
The left front carb (#2) is the control carb, the other carbs are sync'd to it.
You missed something in your cleaning and/or adjustments.
Seve Moreno
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I'm not interested in getting new jets. I'm fine with the stock ones. I did go back and re-sync the carbs and everything did sync up real nicely so that isnt a problem any more.
mavgrab302
Well-Known Member
Mine ran like a top with the dyna plus needles shimmed with washers from radio shack. Lol Guess it has more to do with know how but yes I mentioned Morleys too because he will assist anyone less experienced.
PATMAX
Well-Known Member
Not sure how many remember the “Paul’s Shim Kit”. If you understand tuning these CV carbs, that can help really dial in the right tune but of course, I’d give a nut for an O2 sniffer ! I wasn’t using it anyhow !
DJ Stage ones' are too rich and not worth using.
Then shimming Stage 1's will make it even more-rich, and just the opposite of what you're probably looking to-do. Contact Sean Morley for his set-up. It will be much-less frustrating.
[email protected]
Well-Known Member
Go here and read all the pinned threads. Detailed threads on everything you need to know about these carbs
https://www.vmaxforum.net/forums/carb-tuning.6/
chrisnbeth8
Member
I assume you have a manual or access to one. The genuine manual is good but a little lacking in practical advice. Bite the bullet and remove the carbs. Very easy.Remove air cleaner box by pulling upward. The clamp bolts dont need loosening. Remove left hand scoop and plastic backing plates holding the electrical control units. Disconnect throttle cable block and then the top clamps for each Carby. You will need to lever them up as they sit in a recess in the rubber joint. Lever on the steel rails and not the alloy. You can slide them out the left hand side. All around half hours work. Pretty easy.
Some important things to check. Also, get a full gasket set at the least but maybe a full jet and gasket set. The jet block with main and pilot is in the float bowl and unscrews. Pilots are very fine so you may need a set of carby jet pricks. Lots of carby cleaner and compressed air required. Also check diaphragms and needle to make sure the are secure and not missing the plastic washers, allowing them to float around.
Use a manual and check the jet sizes as some idiot might have decided to jet it with no idea. These things will do a high ten or flat eleven second quarter out of the box so I dont think you need anything more than standard. When you outgrow that then there is plenty of advice from this forum providing you are still alive......
Check the float levels with each carby before refitting. Connect a funnel and some tube to gravity feed fuel into the carby. Fit clear plastic tube to the drain and open the drain screw. Hold it up and the fuel level should be around 16mm below the reference line on the float bowl cover. If they are high then the fuel can run straight down the needle tube into the throat. In my experience, even 5 to 10 mm high may cause this to happen. Sounds a bit like your issue. You can usually see this by removing the air box, start the bike and look at the actions when you blip the throttle. If you see raw fuel flooding in from the needle tube then you have a float issue. If you see the needle jet pistons fluttering too much or different on on side to another then you have a balance issue. Worth doing before removing carbies so you have at least an idea before the carby overhaul. On my recent overhaul, I had to use my original float needle valves as the new ones in the kit would not seal and fuel just kept flowing in regardless of the float height. Might be the case with yours.
When you fit them up then you need to balance them using a set of vacuum gauges connected to the four tubes on the intake manifold below each carby. They are touchy and need to be right. I thing around 170mm mercury minimum and 20mm between each. Follow the manual. Left has one screw which is the start to balance LH front and rear. The rear screw on RH side for front and rear RH. Finally, front screw on RH side to balance right and left. You may need to go through the cycle a couple of times to get it right. Finally set the idle screw.
Advice on mixture screw is old school carby rule. Seat in and out one and a half turns and unless any benifit, leave them as. At most you might get a little leaning out on start in winter and a bit of popping but wont flood in summer time....
Anyway, the effort is worth the reward. If you have not experienced the sheer power and acceleration of a Max running on song then you have missed one on the bucket list and after the experience you will always want to have one. More addictive than the horizontal cha cha. Well almost.....
Some important things to check. Also, get a full gasket set at the least but maybe a full jet and gasket set. The jet block with main and pilot is in the float bowl and unscrews. Pilots are very fine so you may need a set of carby jet pricks. Lots of carby cleaner and compressed air required. Also check diaphragms and needle to make sure the are secure and not missing the plastic washers, allowing them to float around.
Use a manual and check the jet sizes as some idiot might have decided to jet it with no idea. These things will do a high ten or flat eleven second quarter out of the box so I dont think you need anything more than standard. When you outgrow that then there is plenty of advice from this forum providing you are still alive......
Check the float levels with each carby before refitting. Connect a funnel and some tube to gravity feed fuel into the carby. Fit clear plastic tube to the drain and open the drain screw. Hold it up and the fuel level should be around 16mm below the reference line on the float bowl cover. If they are high then the fuel can run straight down the needle tube into the throat. In my experience, even 5 to 10 mm high may cause this to happen. Sounds a bit like your issue. You can usually see this by removing the air box, start the bike and look at the actions when you blip the throttle. If you see raw fuel flooding in from the needle tube then you have a float issue. If you see the needle jet pistons fluttering too much or different on on side to another then you have a balance issue. Worth doing before removing carbies so you have at least an idea before the carby overhaul. On my recent overhaul, I had to use my original float needle valves as the new ones in the kit would not seal and fuel just kept flowing in regardless of the float height. Might be the case with yours.
When you fit them up then you need to balance them using a set of vacuum gauges connected to the four tubes on the intake manifold below each carby. They are touchy and need to be right. I thing around 170mm mercury minimum and 20mm between each. Follow the manual. Left has one screw which is the start to balance LH front and rear. The rear screw on RH side for front and rear RH. Finally, front screw on RH side to balance right and left. You may need to go through the cycle a couple of times to get it right. Finally set the idle screw.
Advice on mixture screw is old school carby rule. Seat in and out one and a half turns and unless any benifit, leave them as. At most you might get a little leaning out on start in winter and a bit of popping but wont flood in summer time....
Anyway, the effort is worth the reward. If you have not experienced the sheer power and acceleration of a Max running on song then you have missed one on the bucket list and after the experience you will always want to have one. More addictive than the horizontal cha cha. Well almost.....
