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I have a 09 kawasaki vulcan 900 i can't throttle it passed 1/4 throttle if i do it just boggs out like it ant getting enough gas has anyone else experienced this type of problem or if someone could point me in the right direction to what might be causing it.
 

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Just had the same problem. Weak batter caused a issue which progressed to damage the fuel pump. Rebuilt the fuel pump with a quantum fuel systems kit (pump is defiantly louder then stock but works) and the issue was better but not completely resolved. Yesterday I disconnected the fuel vent hose and the problem got even better almost perfect but at full throttle she is slow to gain speed. Could this just be the after market fuel pump?
 

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Just had the same problem. Weak batter caused a issue which progressed to damage the fuel pump. Rebuilt the fuel pump with a quantum fuel systems kit (pump is defiantly louder then stock but works) and the issue was better but not completely resolved. Yesterday I disconnected the fuel vent hose and the problem got even better almost perfect but at full throttle she is slow to gain speed. Could this just be the after market fuel pump?

my kit came with 2 new filters mine was bad, appeared almost plugged. Did you replace that too? I will admit i have only got to ride mine little and I am not a hot rodder so it's seldom I crank it hard but since my pump it's back to 100% as far as I can tell. I was very surprised at the filter as I work on old cars and get some that the fuel tank pickup sock has never been changed and they clean as a whistle after years and the bike I have has 10,000 on it so its not high millage or old but it was very plugged. Makes me rethink where i get my gas, or if i should be removing the tank and cleaning every year or tow.
 

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my kit came with 2 new filters mine was bad, appeared almost plugged. Did you replace that too? I will admit i have only got to ride mine little and I am not a hot rodder so it's seldom I crank it hard but since my pump it's back to 100% as far as I can tell. I was very surprised at the filter as I work on old cars and get some that the fuel tank pickup sock has never been changed and they clean as a whistle after years and the bike I have has 10,000 on it so its not high millage or old but it was very plugged. Makes me rethink where i get my gas, or if i should be removing the tank and cleaning every year or tow.
yup, changed the filter. It really happens at higher speeds. lets say I'm going 50 Mi/Hr and need to get to 65 real quick to pass someone I nail down the throttle and she bogs for half a sec and then slowly gains speed. I notice it more since I live on Long Island NY where there is a decent amount of traffic so there are a decent amount of circumstances where I really hit it to try and seperat myself from traffic. its almost like the pump is playing catch up with the demand for fuel.
 

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I have a update. Just took her out for a 33 mile ride. she was running okay, enough power to sufficiently reach 70-80 then by mile 23 I believe she started really acting up on the highway bogging down to 55-60 no power what so ever. I was able to fix this for a couple of minutes by switching off ignition and advancing the throttle all the way then switching on the ignition holding the throttle trying to start the bike by using my speed(every time I tried did not work) pulling clutch back in and using the starter to start the bike back up. After getting to my destination I let her sit for 5min and started her back up and she worked okay as when i first started the ride. Bogging at full throttle and then once I get to around 1/2 throttle a rush of power. Should I see if i can get another pump?
 

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Tydeocean, what you are experiencing may be related to debris in the fuel tank. This would happen when after you start the bike, the filter would slowly start to accumulate debris until it becomes so choked the bike starts to bog down. After you stop the bike, the debris drops off after a few minutes, then you get to do it all over again. Have you shined a flashlight into the tank, to see if there is any debris in the tank?
 

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Tydeocean, what you are experiencing may be related to debris in the fuel tank. This would happen when after you start the bike, the filter would slowly start to accumulate debris until it becomes so choked the bike starts to bog down. After you stop the bike, the debris drops off after a few minutes, then you get to do it all over again. Have you shined a flashlight into the tank, to see if there is any debris in the tank?
Just looked inside the tank through the filler hole and it looks as clean as gas can get. I tipped her to the right side to see if there was anything over by the fuel pump that I could not see but nothing. I took her on a long ride this weekend 100mi, she would cruise at about 55 Mi/Hr but would have no power after that unless I switched the ignition switch off then on again and started her with the starter not the engine. That would give me about a 5 second burst of power and then she slowly came back to 55mph, this worked unit I ran low on fuel about 2gal left in the tank, then she would sit at about 35MPH no matter what I did until I got more fuel. I need to take the tank off to add the front grommets so I will drain the tank and see if I can find any debris, but besides this could it be the relay? The pump primes when she is in neutral not in gear, and if I put her in neutral from being in gear the pump wont prime. Don't know how to test a relay when i'm in the middle of driving, it only does this issue with bogging in gear for the most part. Neutral only acts up every once in a while.

Here is link of how the bike sounds when turning on the ignition. Whats that sound that is not the whirling of the pump?
 

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Found this in the tank accidentally spilled most of the 2gallons I had left on my drive way when trying to refill the tank, so i refilled it with a gallon and a half from the gas station and went off to see how it ran. Way worse, backfiring like crazy through the air intake(scared the hell out of me when I heard a loud bang and then a rush of air hit my leg). after a few minutes the backfiring stopped but the power is still not there. checked the pump and filter while I had it out, everything checks out. I'm going to order the relay and hope that's it, seriously at a loss.

Also not sure if I should start a new thread. I don't want to annoy paynedoug1975 as it seems his problem was solved with a new fuel pump.
 

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Your tank inside surfaces look clean, I could suggest maybe rinsing the tank out (off the bike) with distilled water only (which prevents flash rusting from the tap water minerals), then drying it with compressed air to get the sand out. I would also follow sfair's comments (in other threads) about taking fuel pressure measurements. Your fuel pump does sound a bit odd, from the sound videos you provided. The stuttering sound of the second video in particular sounds odd.
 

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Check fuel lines. Ethanol gas will soften certain rubber compounds causing the fuel lines to collapse under vacuum.
 

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Your tank inside surfaces look clean, I could suggest maybe rinsing the tank out (off the bike) with distilled water only (which prevents flash rusting from the tap water minerals), then drying it with compressed air to get the sand out. I would also follow sfair's comments (in other threads) about taking fuel pressure measurements. Your fuel pump does sound a bit odd, from the sound videos you provided. The stuttering sound of the second video in particular sounds odd.
The pump is new so fuel pressure shouldn't be an issue but ill check anyway. That studdering sound isn't the fuel pump, I'm not positive but it seems like the FI system. If you turn on ignition the FI light turns on and for one second you can hear that same noise but not studdering (not positive on the noise it makes for I have only recently been listening for something wrong). Thinking about it right now Its probably something electrical, this bike has been my daily driver for around a month now(car broke down) and at the begging of this routine the battery was pretty bad so I had to jump the bike with my car(car was off). This happened for about 2 weeks until the new battery arrived, where I would jump it in the morning she would run fine all day and then day-1/2, two days later I would have to jump again. Yesterday I was reading on some forums that this can damage the relay or even worse the FI System, the system doesn't light up to tell me there are codes but I will check that also.

Check fuel lines. Ethanol gas will soften certain rubber compounds causing the fuel lines to collapse under vacuum.
Checked the two fuel lines the bike has, can breath through them very easily. the bike only has 17,000 miles so I wouldn't expect this to be the issue.
 

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Tested the fuel pressure today. I made a little rig so i could drive and test at the same time and its a constant 50PSI, so i'm on to electrical now. Where do I start with this? was going to test stater and rectifier tomorrow then go to CDI( not sure if the bike has one) or the computer system.
 

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Do you still have the fuel pressure regulator from the old pump? The pressure should be around 44 psi or so. Being at 50 might be a bit high. Have you checked your spark plugs? Take a picture of them so we can see how they look.
 

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Do you still have the fuel pressure regulator from the old pump? The pressure should be around 44 psi or so. Being at 50 might be a bit high. Have you checked your spark plugs? Take a picture of them so we can see how they look.
Just changed the spark plugs, the fuel pump is rebuilt with a 400 Kpa pressure regulator so it's good with both of thouse. Tested the stator using Romans 5.8 wright up. I think that is toast. Getting 16v(A to C) to 25v(A to B, and B to C) at idel and 2V( A to B) 16v(A to C) 40v(B to C).
 

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After changing out my stator, and testing my regulator/rectifier I took her out for a test today. still have the problem :mad:. Any other ideas? here is the list of parts replaced and tested, fuel pressure, spark plugs, stator, rectifier/regulator. The only thing I can think of from here is the FI system which I hope is not the issue and don't expect it to be for it the light dose not stay on, just does its normal cycle when the ignition is turned on. I have plans to go on a 4hr trip on Oct.12 so I'm trying to get her working before then.
 

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What might be useful would be to see the fuel pressure while you are riding. Then you could see if the fuel pressure changes, as you begin to lose power. This would confirm or eliminate the fuel system as the problem source.
 

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What might be useful would be to see the fuel pressure while you are riding. Then you could see if the fuel pressure changes, as you begin to lose power. This would confirm or eliminate the fuel system as the problem source.
The picture of my fuel pressure which I posted earlier is the pressure under usage. I drove her 10 miles while she was acting up with the fuel pressure gauge connected no movement up/down steady at 50PSI. Might add to know that the bike backfires every once and a while through the air intake and exhaust, like I said earlier I jumped the bike a few times when the battery was dieing out on me. I think this caused the ECU to fail but before I replace that I would like to test it. do not know where to start with that though.
 
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