Bike running super rich-spark plug chek

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To get an acurate reading the bike has to be under load. So uou have to make a run. 4th gear all the way through the rpm and then kill the engine, coast to the side with the clutch in or in neutral and check a plug. Just free wheeling it in the garage won't be acurate. So now you pulled a plug and it's white or tan.... that means you idle circuit is culprit and needs adjustingI don't really buy inot irridiom plugs. The ignition system on the vmax is not super advanced and a spark plug is only going to through enough spark to get the job done regardless what heat range or type it is. Unless you modify the ignition system just use stock plugs, unless you have money to spend.

Most vmax's will get between 80-110 miles per tanks some freaks will get 130 ( mostly more stock bikes) and some get crappy 60 miles per tank. Depends on mods and how you ride.

If the throttle is crisp and strong then your idle mixture is probably off, if your sluggish and hesitant, your springs maybe be weak or stage 7. Get ride of those and put stock springs in. If you surge you carbs are gunk ed up. If your flat up top your jetting is off.

Make notes at what rpm you have problems or a video helps too. Message Danny max here, he is the carb guru.

Good luck
 
Make notes at what rpm you have problems or a video helps too. Message Danny max here, he is the carb guru.

Good luck

Well it all comes down to if its a tuning problem, or a carb needs to be fixed problem. There are several GREAT tuners on this site....Sean, Mark....and several others. If the problem is openly discussed, then others can also learn.
 
Just thinking out loud, since your vboost isn't working properly, I wonder if its possible that the butterfly valves are stuck in the open position?.....I believe that would make it run rich. Also check your choke plungers to make sure they are all seating properly.
Also something that I noticed that happened two months ago was I used the vboost once while riding and after that no more sound after turning the key, also no vboost at up to 7500 rpm. But it shouldn't affect much the running rich problem. I believe.

Also I found that when bike is at idle and every time I pull the clutch lever I feel a difference in the engine sound, wonder if I'm getting already crazy with this cursed bike or it means anything.
 
Just thinking out loud, since your vboost isn't working properly, I wonder if its possible that the butterfly valves are stuck in the open position?.....I believe that would make it run rich. Also check your choke plungers to make sure they are all seating properly.

If vboost is open at part throttle, it makes the A/F mixture lean, it becomes rich at full throttle. Thats from using the A/F gauge that i have. That is an interesting thought about the choke plungers.
 
To get an acurate reading the bike has to be under load. So uou have to make a run. 4th gear all the way through the rpm and then kill the engine, coast to the side with the clutch in or in neutral and check a plug. Just free wheeling it in the garage won't be acurate. So now you pulled a plug and it's white or tan.... that means you idle circuit is culprit and needs adjustingI don't really buy inot irridiom plugs. The ignition system on the vmax is not super advanced and a spark plug is only going to through enough spark to get the job done regardless what heat range or type it is. Unless you modify the ignition system just use stock plugs, unless you have money to spend.

Most vmax's will get between 80-110 miles per tanks some freaks will get 130 ( mostly more stock bikes) and some get crappy 60 miles per tank. Depends on mods and how you ride.

If the throttle is crisp and strong then your idle mixture is probably off, if your sluggish and hesitant, your springs maybe be weak or stage 7. Get ride of those and put stock springs in. If you surge you carbs are gunk ed up. If your flat up top your jetting is off.

Make notes at what rpm you have problems or a video helps too. Message Danny max here, he is the carb guru.

Good luck
You do not need to go through 4 gears just 1-
I use iridium plugs before and after i installed cops and they make a difference either way.
I lowered the gap to from 35 to 27 when i made the cops and i run vboost open at all times.
122 mpt at sea level.
If your throttle is crisp and strong then your idle mixture is probably NOT off.
 
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You do not need to go through 4 gears just 1-
I use iridium plugs before and after i installed cops and they make a difference either way.
I lowered the gap to from 35 to 27 when i made the cops and i run vboost open at all times.
122 mpg at sea level.
If your throttle is crisp and strong then your idle mixture is probably NOT off.

122 mpg would you tune mine :punk:
 
122 mpg would you tune mine :punk:


clapping.gif
 
122 mpg at sea level.
Mee to??? Pleeeeeeeese

That would be something like 488 miles to the tank.. Sweet. :rofl_200:
 
You guys might be disappointed I hear part of his tuning involves disconnecting the driveshaft !!! LOL
 
Seriously- Do i need to correct that or do we need to stay in school?:rofl_200:
Knuckleheads PER TANK-GEEEEEEEEEEES:clapping:
And since you were being so sarcastic tune it yourself!!!:eusa_dance:
And CC gets nothing for all HIS typos? I thought he was DRUNK!!!
 
Hey we all make mistack's just a little friendly poke.........:eusa_dance::nyah nyah:
 
I usually type from a phone. So it auto corrects, hence my post below my original post.

And I never said through all the gears, I said 4th gear all the way through. ;)
 
When I had the 270 sprint I tried Iridium plugs. I started having jetting problems. To make a some what of along story short. I called the tech. department at NGK & asked them if the iridium plugs ran hotter then a regular plug & they said yes. I found them to be very unstable & would not use them. If your just a tick lean on jet it goes lean & if your a tick rich it goes rich. Lots of luck trying to get that sweet spot.:confused2:
 
When I had the 270 sprint I tried Iridium plugs. I started having jetting problems. To make a some what of along story short. I called the tech. department at NGK & asked them if the iridium plugs ran hotter then a regular plug & they said yes. I found them to be very unstable & would not use them. If your just a tick lean on jet it goes lean & if your a tick rich it goes rich. Lots of luck trying to get that sweet spot.:confused2:
It does take time to find it but the numbers prove it's worth it.
I do not agree that using it as a hotter plug will make it richer though.
Every bike i've ever owned that ran rich ran better and got better gas mileage when i changed to it.
 
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I usually type from a phone. So it auto corrects, hence my post below my original post.

And I never said through all the gears, I said 4th gear all the way through. ;)
Who said you said through all gears?
Actually 2nd, 3rd and 4th you are doing the exact same thing that is not necessary.
 
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