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gen 1 vmax is running on seemingly all cylinders but feels way down on power.

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kvb34441

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A new problem has started with my vmax. I replaced the battery recently, (about 3 days ago) and ever since then, it has felt way down on power. I thought the spark plugs might have been the problem, so I pulled them out only to find that they were actually decent. But I replaced them anyway, checked spark, all good. Took it on a test ride, same problem. Not sure where to go from here.
 

Pighuntingpuppy

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I would be wondering fuel quality. Did you top off the tank before battery replacement? Aside from that, I would go looking for pinched wires under the battery. Maybe disconnect the ground from the chassis and clean it up good and tight. Another thing.....is the battery you put in actually any good? Dead cell can make it start and run but 10v is not 12v and the charging system is protesting the low battery voltage.
 

kvb34441

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well now that you mention it, I was running 93 octane, I wanted to see the difference between premium and regular. Maybe the sudden switch could've effected it? I checked the battery with 2 different volt meters at different rpm's and as far as I can tell the battery is just fine. I'll check for pinched wires and let you know how it goes.
 

MaxMidnight

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IMO it isn't a battery problem, if the bike will start you will have sufficient power in it for the ignition to work.
You are either not running on all cylinders (the bike that is, not you) or you have a fueling issue.

Given that it started after you changed the battery I would start by checking the connections and wires around the coils.
 

Parminio

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I think you think you're hitting on all cylinders and you're not.

When you pull that wire bracket off to remove the battery, it is very, very easy to pull a wire out of a coil. It doesn't have to be all the way out for you to lose it.

Take your seat back off and make sure the two top coil wires are pushed all the way in.
 

jmdclan

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Poor power due to dirty fuel jet circuits in the carbs, boys!
Very common and happens every couple three years or so to my 94 max. The cure? The "shotgun" method of cleaning the carbs and syncing them with 4 vacuum gauges after blowing all the carb circuits out with carb cleaner and compressed air. You will have to google it as I haven't memorized the correct procedure but its online somewhere. Do this and your max will be back to normal. Also you need to pick up the metric "o" ring set from Harbor freight . Good luck
 

Fire-medic

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Poor power due to dirty fuel jet circuits in the carbs, boys!
Very common and happens every couple three years or so to my 94 max. The cure? The "shotgun" method of cleaning the carbs and syncing them with 4 vacuum gauges after blowing all the carb circuits out with carb cleaner and compressed air. You will have to google it as I haven't memorized the correct procedure but its online somewhere. Do this and your max will be back to normal. Also you need to pick up the metric "o" ring set from Harbor freight . Good luck
So he clogged a jet by changing the battery?

Odd.
I've frequently mentioned the pilot jets becoming clogged, and then interfering with idle and off-idle throttle response. Where the shotgun sometimes works, I just resign myself to a carburetor tear-down and removal of the jet block, and removal of the pilot jets (part # 42) and the 'main bleed jets' (part #44) to fix it properly. Before you do anything, check your gas tank for any rust or deposits on the interior, and consider replacement of the gas filter. Why? Because spending the time to disassemble the carburetors, to clean them, and to re-assemble/re-install them is a waste of time if you have a dirty gas filter and a rusty, corroded gas tank interior. It's just gonna clog the pilot jets and the main bleed jets again.

VMax carburetor.png

Clogged pilot jets cause non-firing cylinders at idle, poor off-idle throttle response, and make it impossible to do anything worthwhile for your carburetor synchronization and air-bleed screw settings.

ew adjustment.
 
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Fire-medic

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Someone could have a dirty gas tank, a clogged fuel filter, worn-out brake pads, shot clutch friction discs, tires showing cord, and be riding every-day. I'm not sayin' that's you. Daily use doesn't confer any status other than, "It started, again." It is better for things like seals and gaskets.
 

Julian Tomkins

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have you tried squirting water at your exhausts to see if they are all equally hot, try it at idle and after holding the revs up for a bit
 

Traumahawk

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Correlation does not mean causation. Actually it could be 2 separate issues. Occums razor says that all things being equal, the simplest answer (most likely answer) is usually correct. Now.....messing with the batteries probably means a coil wire that was bumped or pulled out just a bit. While your there clip about 1/4 of an inch off the end of the wire to clip off any corrosion.

BUT, the gen 1 is VERY susceptible to a clogged pilot jet, and will usually happen all of the sudden, so people think that its electrical in nature. Paper fuel filters let CRAP thru, especially if there is rust in the tank...etc.

So do a shotgun as well. Its very easy to do, and I know of people that do one everytime they change the plugs to keep the bike running crisp. Here are the directions. The only deviation that I do from the standard directions is to take out PAJ#2, to be able to get a full blast of air into the carbs. I learned it the hard way, and had a "clog" that I couldnt get rid of after 3 shotguns....and by adding the one step to get a full blast of air, the clog came out the 1st time. This was all done in one night because I had some dyno time reserved for in the morning on the 07.

 

Fire-medic

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Correlation does not mean causation. Actually it could be 2 separate issues. Occums razor says that all things being equal, the simplest answer (most likely answer) is usually correct. Now.....messing with the batteries probably means a coil wire that was bumped or pulled out just a bit. While your there clip about 1/4 of an inch off the end of the wire to clip off any corrosion.

BUT, the gen 1 is VERY susceptible to a clogged pilot jet, and will usually happen all of the sudden, so people think that its electrical in nature. Paper fuel filters let CRAP thru, especially if there is rust in the tank...etc.

So do a shotgun as well. Its very easy to do, and I know of people that do one everytime they change the plugs to keep the bike running crisp. Here are the directions. The only deviation that I do from the standard directions is to take out PAJ#2, to be able to get a full blast of air into the carbs. I learned it the hard way, and had a "clog" that I couldnt get rid of after 3 shotguns....and by adding the one step to get a full blast of air, the clog came out the 1st time. This was all done in one night because I had some dyno time reserved for in the morning on the 07.

Spell Check! It's "Occam's razor." ;) And I see that someone paid-attention in Statistics class.

I do agree that the pilot jets are susceptible to obstruction. I'd just as-soon remove the carburetors, and do it properly (split the carbs into two pairs), and remove the float bowls, and the jet blocks. That-way, you see everything.

I have a sintered-bronze, cleanable/replaceable element fuel filter, they're cheap, and they fit in the OEM space, a good way to-go.
 

Traumahawk

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Spell Check! It's "Occam's razor." ;) And I see that someone paid-attention in Statistics class.

I do agree that the pilot jets are susceptible to obstruction. I'd just as-soon remove the carburetors, and do it properly (split the carbs into two pairs), and remove the float bowls, and the jet blocks. That-way, you see everything.

I have a sintered-bronze, cleanable/replaceable element fuel filter, they're cheap, and they fit in the OEM space, a good way to-go.
I'm from Oklahoma, You better be glad that I didnt spell it Arkhams.....LOL.

I have a bronze filtered sintered filter on mine as well ( Earls) . Dannymax was telling me about information that was posted years ago about how bad paper filters actually are. Maybe it was RaWarrior that posted it? 🤔
 

Fire-medic

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I'm from Oklahoma, You better be glad that I didnt spell it Arkhams.....LOL.

I have a bronze filtered sintered filter on mine as well ( Earls) . Dannymax was telling me about information that was posted years ago about how bad paper filters actually are. Maybe it was RaWarrior that posted it? 🤔
I don't think a paper filter is evil, obviously, it's better-than none. I'm sure there are different levels of particulate filtering capacity available, pick one to fit your pocketbook and the level of protection you need. I have the EMGO version of the Earl's scew-together filter. Other than rinsing the bronze element and blowing it out, I've never replaced the filter. If it ever does become plugged, you can take a propane torch to it, and burn-off the accumulated crud, and rinse/blow it out, and re-install it.

Since DannyMax is one of the elder experts on our induction capacities, I would heed his input.

On a different topic, have you watched the Lovecraft Country series, we've watched a couple, and will continue to-watch. BTW, my diploma is in Eldritch Geneological Anatomy and Physiology, from Miskatonic University. 😱👿👹👻💀
 
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Parminio

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I've run the factory filter since day one out of the crate. Never had an issue.
 

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