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Could you please post a picture of the spark plugs.
Also, when were the valves last checked?
Spark plugs where just changed, I wont be able to take them out until late tonight

Bike has never had valve check. But from what I understand many have gone to 30k miles without a valve check eventhough the check is at 15k. I'm not sure If I included that fact that I jumped the bike with cables when I had the battery issue not being aware that some have had the ECU fail from doing this.
 

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Bike has never had valve check. But from what I understand many have gone to 30k miles without a valve check eventhough the check is at 15k. .
Ooooh, not good. Never assume what applied to others applies to you. Extend Kawasaki recommended maintenance schedule at your own risk. Especially the first one.

Do a valve check ASAP.

Awaiting plug photos.
 

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Bike has never had valve check. But from what I understand many have gone to 30k miles without a valve check eventhough the check is at 15k. .
Awaiting plug photos.
Front Plug 20191003_193952_1570146884160.jpg

Rear Plug(has socket on it)

I will get to the valves as soon as I can, hopefully this weekend but I have a extremely busy week ahead of me with 3 different beginning engineering midterms. The valves wont cuases this bogging issue right? I thought that if they need adjustment it would cuase a loss of rpm that was consistent and I would hear them ticking.
 

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OK:

1. Your fuel pressure is out of spec. (too high). Fuel pressure is critical for correct engine performance.
Sometimes aftermarket parts can be one size fits all and not perform as they should. My hearing is not what it once was, but that pump sounded pretty gnarly, to me. Maybe the regulator is in backwards or not the correct one.

2. Valves, as they age, get quieter, not noisier (tighten up) A tight valve can cause all kinds of driveability issues until they eventually burn.

3.You are showing a difference between plug coloring, which shouldn't be.
The front plug is showing lean. Maybe that injector is partially plugged making that cylinder run lean.

Post back with any questions.
 

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OK:

1. Your fuel pressure is out of spec. (too high). Fuel pressure is critical for correct engine performance.
Sometimes aftermarket parts can be one size fits all and not perform as they should. My hearing is not what it once was, but that pump sounded pretty gnarly, to me. Maybe the regulator is in backwards or not the correct one.

2. Valves, as they age, get quieter, not noisier (tighten up) A tight valve can cause all kinds of driveability issues until they eventually burn.

3.You are showing a difference between plug coloring, which shouldn't be.
The front plug is showing lean. Maybe that injector is partially plugged making that cylinder run lean.

Post back with any questions.
1. The aftermarket fuel pump has a pressure regulator of 400kpa and its known to be a good aftermarket pump from what I have seen.

2. Checked the valves today all allowed the largest shim for the range .25mm on the exhaust and .15mm on the intake ex fee GB gcept one front intake valve which was .11m so still in spec.

3. The plug picture of the rear only showed the one side the other is black, I'll include it in this post. I will test for a mechanical issue in the injector tomorrow but both tested good at 12ohm.

4. Checked the coils just to make sure, they also check out good.

If it's not the injector Im lost as what it is. Im questioning this with the bike cold is the wrong step to take because I have the problem while running and after until I leave the bike for a little.
 

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1. It would be the fuel pressure regulator, not the pump, at fault.
2. One cannot expect an engine to perform correctly with fuel pressure that is out of range. If you do not correct that, somehow, you will be just spinning your wheels and wasting time. Fuel pressure is critical.
No other issues can be addressed (plugs, injectors, etc.) until that is remedied.

Sorry.
 

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Tydeocean, what is the plug gap? From the pics they look a bit wide, but that could just be the pics. If they are wide, that could be an issue because the coils can only produce so much spark. I agree with sfair, the front cyl appears to run leaner than the rear one. Fuel injector cleaner might help with this, like Red Line SF-1.

I also agreed earlier with sfair, the fuel pressure is a bit high. I noticed you can order the pressure regulator separately from the Quantum website, and it's like $10-$20 bucks, something like that. If I remember the numbers correctly, the pressure should about 44 PSI or so. The reason that's important is because the ECU runs open loop on most VN900s. That means without O2 sensors, the ECU times the injector pulse width based on the assumption that the fuel pressure is correct. If the pressure is off, the mixture will be off, and without O2 sensors the ECU has no way of knowing.
 

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1. It would be the fuel pressure regulator, not the pump, at fault.
2. One cannot expect an engine to perform correctly with fuel pressure that is out of range. If you do not correct that, somehow, you will be just spinning your wheels and wasting time. Fuel pressure is critical.
No other issues can be addressed (plugs, injectors, etc.) until that is remedied.

Sorry.
Tydeocean, what is the plug gap? From the pics they look a bit wide, but that could just be the pics. If they are wide, that could be an issue because the coils can only produce so much spark. I agree with sfair, the front cyl appears to run leaner than the rear one. Fuel injector cleaner might help with this, like Red Line SF-1. I also agreed earlier with sfair, the fuel pressure is a bit high. I noticed you can order the pressure regulator separately from the Quantum website, and it's like $10-$20 bucks, something like that. If I remember the numbers correctly, the pressure should about 44 PSI or so. The reason that's important is because the ECU runs open loop on most VN900s. That means without O2 sensors, the ECU times the injector pulse based on the assumption that the fuel pressure is correct. If the pressure is off, the mixture will be off, and without O2 sensors the ECU has no way of knowing.
I will call Quantum tomorrow to ask what kpa that regulator which is sold separately is and get it if its is the right one, but I have trouble believing that is the issue do to the fact that the bike runs fine for the first couple of minutes from cold and then once hot(and bogging) if I switch the ignition power is restored for a couple of seconds ( all of this when tank is above half full). I thought that if it was a pressure issue it would always have a problem for the pressure is always are 50
 

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Cold motors always run rich, at least for the first 2-4 minutes, because combustion is incomplete. For injected motors, the ECU does that. After a motor warms up, combustion is more complete, but a warm motor can run rough if it's too rich. An O2 sensor is very helpful in controlling the mixture, but most VN900s don't have these. Your idea about calling Quantum sounds good. It would be really nice if they had the tested pressure stamped on the side of the regulator or the box or something like that.

To add, by controlling the pressure, you are controlling the mixture. Because the bike has no O2 sensors, the fuel maps within the ECU were set after testing at the factory, and there is no way to change them (short of an ECU flash, which is a different subject entirely). Getting the pressure to factory spec gets the mixture to factory spec. It's a shame there is no adjustment for the fuel pressure.
 

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1. It would be the fuel pressure regulator, not the pump, at fault.
2. One cannot expect an engine to perform correctly with fuel pressure that is out of range. If you do not correct that, somehow, you will be just spinning your wheels and wasting time. Fuel pressure is critical.
No other issues can be addressed (plugs, injectors, etc.) until that is remedied.

Sorry.
Cold motors always run rich, at least for the first 2-4 minutes, because combustion is incomplete. For injected motors, the ECU does that. After a motor warms up, combustion is more complete, but a warm motor can run rough if it's too rich. An O2 sensor is very helpful in controlling the mixture, but most VN900s don't have these. Your idea about calling Quantum sounds good. It would be really nice if they had the tested pressure stamped on the side of the regulator or the box or something like that.

To add, by controlling the pressure, you are controlling the mixture. Because the bike has no O2 sensors, the fuel maps within the ECU were set after testing at the factory, and there is no way to change them (short of an ECU flash, which is a different subject entirely). Getting the pressure to factory spec gets the mixture to factory spec. It's a shame there is no adjustment for the fuel pressure.
Found the OEM pressure regulator and installed it. Pressure without bike running is 40psi, with running and under load (up to 75mph) is 37ish. I thought we had solved the problem when we installed the OEM pressure regulator, I started her up let her sit for about two minutes and she sounded fine. On the road is was great, got up to 75 like normal. Was on my back from the short test drive, about 3 miles total when she started acting up the worse she ever has. Got to a stop sign and she stalled, started her back up and she started bogging until eventually she was just backfiring through the air intake and going 5mph. Then she just died and would not start, killed my battery trying to get her back. Tested my battery and charging system before I left battery was at 13v idle and around 14v 3k RPM
With out ignition on she sate at 12.8v
 

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1. Check fuel flow rate, engine hot.
2. Recheck plugs and tell us what you see. It would be nice to check right after when the engine is acting up, particularly after a no start.
3. Fuel pressure now looks low.
 

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Agree with sfair, who can correct me if I'm wrong, but I believe the correct pressure is 44 PSI. It's possible a fuel tank vent is blocked, that's why sfair suggested running with the filler cap loose. If this works, then you know the tank vent is blocked some where. The bike starts out great, then gets worse as the vacuum builds in the fuel tank.
 

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I did not have enough time to do the diagnosis myself so I brought it to my dealer and its a good thing I did. Apparently my pressure gauge was not reading correctly, where it would get stuck at 50psi and not read that it was still dropping pressure. According to the head mechanic the quantum fuel pumps are of poor quality, the pressure is fine at 50psi but that doesn't matter if the pump can't pump it. This has put the bike in the shed until next season when I can afford a $400 pump or find a good quality replacement. Thanks for all the help anyway's guys.
 

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1. 50lbs. is not OK. Factory specs have to be met for correct fuel metering.
2. OEM can, at times be very pricey, but the parts always fit and function correctly. It can come down to how many times you want to do the job.
 

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OK, I'm confused. Previously, before the fuel pump was rebuilt, you said the fuel pressure reading would go down to about 17 psi (?) during the bogg. That sounds like a normal fuel starvation issue, After the first fuel pump rebuild with a Quantum fuel pump, you stated your fuel pressure was 50 lbs at idle. Then you said as you rode the bike, the pressure would drop into the 43-44 psi range at speed. Then you replaced the pressure regulator with a (so called) OEM one, that gave you 40 PSI at idle, that would then drop to 37ish at speed. That so called OEM prssure regulator is not up to spec. Then you took the bike to the dealer, they said your pressure tester gave you a "frozen" reading of 50PSI (CANNOT be true, since you had variable pressure readings). So now they are recommending replacing the pump with a new factory fuel pump. You know that will be expensive, but in all fairness, this may actually fix your problem. Given all this, the decision is up to you.

So, going back to your original post, when you gave us the initial pressure readings, where the pressure would drop to 17 PSI (?) at speed, that does sound consistent with the symptoms you were experiencing. So replacing the fuel pump with a factory fuel pump may very well correct the issue (assuming there is no venting issue, or fuel line issue, etc). In another thread, I posted a video showing a fuel pump rebuild with a Quantum fuel pump for a VN900. At the time, I was happy to see that there was an alternative to the expensive factory pump. Now I'm starting to wonder if that was a good idea. It seems the quality control that could be there for a good low cost alternative, clearly is not there, so disappointing.
 

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1. 50lbs. is not OK. Factory specs have to be met for correct fuel metering.
2. OEM can, at times be very pricey, but the parts always fit and function correctly. It can come down to how many times you want to do the job.
1. Just restating what the dealer told me
2.Yea, and with no viable alternative this looks like the road to go down.
OK, I'm confused. Previously, before the fuel pump was rebuilt, you said the fuel pressure reading would go down to about 17 psi (?) during the bogg. That sounds like a normal fuel starvation issue, After the first fuel pump rebuild with a Quantum fuel pump, you stated your fuel pressure was 50 lbs at idle. Then you said as you rode the bike, the pressure would drop into the 43-44 psi range at speed. Then you replaced the pressure regulator with a (so called) OEM one, that gave you 40 PSI at idle, that would then drop to 37ish at speed. That so called OEM prssure regulator is not up to spec. Then you took the bike to the dealer, they said your pressure tester gave you a "frozen" reading of 50PSI (CANNOT be true, since you had variable pressure readings). So now they are recommending replacing the pump with a new factory fuel pump. You know that will be expensive, but in all fairness, this may actually fix your problem. Given all this, the decision is up to you.

So, going back to your original post, when you gave us the initial pressure readings, where the pressure would drop to 17 PSI (?) at speed, that does sound consistent with the symptoms you were experiencing. So replacing the fuel pump with a factory fuel pump may very well correct the issue (assuming there is no venting issue, or fuel line issue, etc). In another thread, I posted a video showing a fuel pump rebuild with a Quantum fuel pump for a VN900. At the time, I was happy to see that there was an alternative to the expensive factory pump. Now I'm starting to wonder if that was a good idea. It seems the quality control that could be there for a good low cost alternative, clearly is not there, so disappointing.
Yes to all except the gauge, maybe I miss spoke. They did not tell me what was broken about the gauge just when they switched my gauge out and used theirs instead they where getting a drop in pressure to 15-20psi during bogging conditions. Like sfair said in a prior post the pump sounds off, and as time has gone on it has gotten worse. It's very loud and just sounds bad. In the end would not recommend a quantum fuel pump, going to call them up to see if i can get some type of reimbursement for all this time and $$ spent.
 
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