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Discussion Starter #21
Reading back over your posts;

(Forgive me if I missed this in your replies)

Fuel/Gas Cap ? Did you try and ride the bike with the cap open ?

You say that the fuel pump was replaced , was that with a drop in replacement for the pump itself or the whole pump assembly system?
Those rubber O-rings in the fuel pump assembly could be seated incorrectly or the fuel pressure regulator might not be out of position/direction

Your bike has a custom exhaust system.. has the clean air mod been done ? Is the bypass vent that the crank case uses closed up ?

The revs staying up for a long time could be an indication of the air system being out of correct settings..

When the bike starts up it measures air from the sensor mounted to the air cleaner element housing (as the airbox is called in the manual)
If that reading is out of range the ecu can put the bike into one of the two restricted modes..

BUT then you would be getting a fault code if I'm not mistaken?
The fuel pump was a rebuild kit that came with brand new everything, pump, electrical leads, O Rings, I put a new regulator in. The only OEM part in the actual plastic housing for the fuel pump. I have taken that fuel pump out probably 5 or 6 times and meticulously combed through it and I’m positive that it is correct. And no, it doesn’t have the clean air mod. And your question about the fuel cap confused me a bit. I have not tried riding the bike without the fuel cap on. What would that do?
 

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The fuel pump was a rebuild kit that came with brand new everything, pump, electrical leads, O Rings, I put a new regulator in. The only OEM part in the actual plastic housing for the fuel pump. I have taken that fuel pump out probably 5 or 6 times and meticulously combed through it and I’m positive that it is correct. And no, it doesn’t have the clean air mod. And your question about the fuel cap confused me a bit. I have not tried riding the bike without the fuel cap on. What would that do?
I saw it was a suggestion to your 1st post and I didn't think to ask you what happened when you rode with the tank open..

It may sound like an odd suggestion but I WOULD DEFINITELY recommend testing your bike;
- with the tank gas cap just a bit open
* its also in the workshop manual under troubleshooting the DFI fuel injection system

These bikes and many others vent through the over flow pipe at the back of the fuel tank and ALSO through the gas cap itself..

It's called a "labyrinth" with good reason.. I've taken mine apart twice now and (holding my breath) today was the first time I've retested the bike without the exact same symptoms returning..

If you do find that the bike rides better with the cap open you've narrowed down your problems by quite a big margin..

If the cap isn't venting at all it will affect the pressure/equalisation in the tank
.and in turn the ability of the pump to draw in more fuel than priming the fuel pump allows..

That's loosely from what I've read (and I'm really just restating what others have explained to me)

When you take the pump apart , I'm betting that it ran better after that for a bit ? Mine does the exact same thing..

I've rebuilt my gas cap (a horrible job) as best I can.. but busy trying to source a replacement.

If you do strip your gas cap down and clean out the junk in there ...
be careful to mark out which of the tiny springs go where..
if you unscrew the 'gasket rubber mounting plate' (that metal plate that keeps the rubber seal in) be very careful not to flip the top of the cap over.. because those tiny parts will go flying everywhere !

You'll see a lot of crap in there I bet..
 

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The gas cap makes a fairly good air tight seal to the tank. As fuel is sucked out by the pump, the air gap at the top between the fuel and Tank increases in volume. If no air enters the tank, air pressure goes down. When it drops far enough, the pump will not be able to draw out more fuel. The vent line allows atmosphere to move in and out of the tank to allow the pump to keep working
 

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Discussion Starter #24
I actually put a new gas cap on mine when I bought it because the other was a POS. I’m hoping it may be just a combination of small little problems that I didn’t know to check for when I get it back from the shop.
 

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I actually put a new gas cap on mine when I bought it because the other was a POS. I’m hoping it may be just a combination of small little problems that I didn’t know to check for when I get it back from the shop.
At this I'm not even sure where to start with mine.. first proper test and it's like nothing has changed ..
Practically un-ridable .. it really feels like it's getting choked off and the more you pull on the throttle the worse it feels..

No idea where to check next.. hopefully you fare better than me when you get it back from the shop
 

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Discussion Starter #26
At this I'm not even sure where to start with mine.. first proper test and it's like nothing has changed ..
Practically un-ridable .. it really feels like it's getting choked off and the more you pull on the throttle the worse it feels..

No idea where to check next.. hopefully you fare better than me when you get it back from the shop
That’s exactly how mine feels. It has no power, but especially when I twist into the throttle it completely falls on its face. When I get it back from the shop I will be sure to update you with the exact cause of the problem and that may be able to give you direction as to the next step to take.
 

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That’s exactly how mine feels. It has no power, but especially when I twist into the throttle it completely falls on its face. When I get it back from the shop I will be sure to update you with the exact cause of the problem and that may be able to give you direction as to the next step to take.
Any update with how this went?
 

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Any update with how this went?
I overhauled the crap out of the fuel pump assembly (pump itself , tbag strainer and the plastic housing that sits above the fuel pump - where the regulator is).. I threw a lot of bicarb in the plastic housing as some people say there's a second filter there (although I've never confirmed that) then dumped it in vinegar.. let it soak for a few minutes and then washed it out with warm soapy water before soaking it in fresh gas.
I also scrubbed the tank out even though it looked 'ok' .. the issue was definitely in the tank but swapping the strainer wasn't the problem..
So deep clean the entire fuel system in the tank.. go through the ground wires connected to the fuel pump. My bikes been pulling like a freight train since then . .. sat with that shit for so long I actually had to relearn how my bike handled 😅😅
 

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I've got the exact same problem.sat for a while then ran like crap.replace fule pump with the rebuild pump and filter replacement and regulator o rings are good .replaced plugs and removed and cleaned upper and lower injectors and full rail. Fuel line look good not kinked.bike is stock except for kn air filter.wont rev past 4k .haven't replaced the air cleaner element and didn't know it would put the bike in a limp mode so there's my next part to buy hopefully it works.
 

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I also cleaned that top section of the fuel pump there is a filter in there..didn't use vinegar so thats next..used fuelsystem cleaner...but like you said the problem. Seems to be in the tank
 

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also the exhaust makes my eyes burn not sure what that means ..did do that before ..I work on mine in a small shop and its ran I. There for 30 mins before with vent fan on .now I can't even be in there for 5 mins with the fan on.i don't know if it means running rich or lean or nothing at all
 

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At this I'm not even sure where to start with mine.. first proper test and it's like nothing has changed ..
Practically un-ridable .. it really feels like it's getting choked off and the more you pull on the throttle the worse it feels..

No idea where to check next.. hopefully you fare better than me when you get it back from the shop
 

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The change in how noxious the exhaust is, results from what is in the fuel tank. Solvents in the fuel system cleaner are much more toxic than regular gas -- which wasn't good for your health in the first place. It should be OBVIOUS that running that bike inside a building with limited ventilation is a very bad idea.

When a bike sits for months, with les than a full tank of gas the fuel that IS there, evaporates. But it doesn't do so equally. The parts of the fuel that burn most easily have the shortest molecules. That means they evaporate first, which makes the fuel that remains harder and harder to ignite. This heavier stuff that remains, is what forms the varnish in fuel systems. The varnish is sticky, tar like stuff.

Modern fuel with alcohol in it degrades even faster than 'straight' fuel does. The alcohol absorbs moisture out of the air and will form jell like substances in the tank, to add further grief.

Storing a bike with fuel stabilizer in the gas, and having that tank topped all the way up as far as you can, limits how much air can move in and out of the tank. The air in the tank expands when the tank warms, and contracts when it cools. Every time the air inside cools, it draws in more air from outside the tank. Whatever moisture is in that air, becomes trapped in the fuel tank. The lower the level of fuel in the tank, the greater the exchange of air from outside it to inside.

Were I you.... Pull the tank off the bike. pull out the pump, and clean the inside of the tank. If there is any rust present, remove it, and line the tank to prevent any more rust from dropping into your fuel supply.
 

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Have the fan on to clear the fumes but I stop and wait for it to clear...I've done every thing I can think of pulled and drained the tank ,replaced fuel pump and filter and regulator, cleaned all orifices I could find and tank lines and vent lines and fuel tank cap vent. Clean fresh fuel cleaned and chew injectors top and lowersalong with the fuel rail.i can't see the top injectors fire but I'm assuming its due to it not getting into the higher rpms
 

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fixed...had to thoroughly clean upper fuel pump cap used the baking soda and white vinegar ..packed the cap full of baking soda and dropped it in a Mason jar of vinegar ,bubbled like crazy for a few mins and rinsed with warm soapy water..put the pump back together and popped it in the tank fired right up.funnybtjing is I had that cap off numerous ti.es cleaning it with injector cleaner and carb cleaner but the vinegar got out whatever it was ...thanks again. Im So sorry I can find who suggested it ....to you sir a sincere hand shake. I hope this helped someone else as well .thank you all again
 

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fixed...had to thoroughly clean upper fuel pump cap used the baking soda and white vinegar ..packed the cap full of baking soda and dropped it in a Mason jar of vinegar ,bubbled like crazy for a few mins and rinsed with warm soapy water..put the pump back together and popped it in the tank fired right up.funnybtjing is I had that cap off numerous ti.es cleaning it with injector cleaner and carb cleaner but the vinegar got out whatever it was ...thanks again. Im So sorry I can find who suggested it ....to you sir a sincere hand shake. I hope this helped someone else as well .thank you all again
You're welcome man! It was a "long shot" idea when I did it .. but blew my mind when it actually worked (y)
 

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Hey your long shot worked...its a beast...thank you again ..I had that same part open I don't know how many times cleaning and spraying...guessing those bubble agitated it enough to knock that crap outta there.thank again
 

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Hey your long shot worked...its a beast...thank you again ..I had that same part open I don't know how many times cleaning and spraying...guessing those bubble agitated it enough to knock that crap outta there.thank again
Lol very glad to hear that your bike is sorted...

Yeah I went through the same thing.. nealy drove me batshit mental to put it plainly. Tried all the fuel cleaners as well and it made zero difference...

I wouldn't try vinegar on the fuel pump itself because I don't think those things are super resilient to something that acidic.. but the tbag filters and housing, briefly soaked and then left overnight in clean gas .. (y)
 
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