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Discussion Starter · #1 ·
hey guys,
i have a problem with my bike and that is why i am in here lol.
when i had a bone stock bike i never had any problems with it im an aggresive rider love roll racing.
after i got my bike flash/tune and on e85 on different map my bike been running like sh*t.
ran fine for about a week or two and then the problems started. My fuel pump went out. so i replaced it with a quantum fuel pump. after that day or two after started bogging and sputtering after 11k rpm. took it to get it fixed so the injectors got cleaned up, then after would bogg after 5k rpm. long story short, switched out; plugs, coil, throttle bodies, fuel pump, fuel pump regulator,cleaned injectors like 3 times (replaced injectors with injector rails twice), the whole fuel pump assembly, cleaned out the air filter and air box, made sure not to have any kinked lines.

bike runs good but when full throttle it bogs and when released a bit it goes. im running on ideas what could be wrong with it. any of yall can help me out with some tips or advices would greatly appreciate it. oh and by the way is not throwing any f1 codes. i have my healtech by passed thru the app. when i have it on and full throttle it shows "c24 c25 c26 c27" which is the igniton codes. but like i said when is bypass no codes.
 

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Welcome to the forum.

This symptom has popped up a few times in the last month or so and it is usually a fuel delivery problem.

I first suggest to do a fuel pressure and volume check as per the service manual.
 
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Discussion Starter · #3 ·
Welcome to the forum.

This symptom has popped up a few times in the last month or so and it is usually a fuel delivery problem.

I first suggest to do a fuel pressure and volume check as per the service manual.
Fuel pressure is good..we cleaned the top injectors changed the air filter installed a brand new pump and regulator and still no luck 😢
 

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What fuel pressure did you measure and how much fuel was discharged in 10 seconds?
 

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Discussion Starter · #8 ·
What fuel pressure did you measure and how much fuel was discharged in 10 seconds?
But just out of curiosity we tried two different pumps (new ones with new filters and new regulators) one was a quantum and the other one was a regular fuel pump would it still give me a bad reading? The pumps are on two different tanks one for e85 and one for super unleaded
 

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But just out of curiosity we tried two different pumps (new ones with new filters and new regulators) one was a quantum and the other one was a regular fuel pump would it still give me a bad reading? The pumps are on two different tanks one for e85 and one for super unleaded
43 is good, you should have about 6 ounces in 10 seconds with open flow.

The two tests confirm the whole assembly. (pump, seals, filters, regulator, etc). Till you know for sure it is in spec, you are just guessing. A nicked o-ring, bad or loose regulator or incorrect assembly have caught out a number of "new pump" owners.

Did you or someone else mention checking for a kinked fuel line when the tank was lowered?

Also, you mentioned "new ones with new filters". Are you talking about the tea bag filter on the bottom or have you also replaced the high pressure filter in the plastic housing next to the pump?
 

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Throttle body/secondary butterfly valves might not be opening fully. Remove air box to expose the throttle body and while bike running rev engine if the don’t open fully that’s your issue. Had this problem and ended just unscrewing them removing completely leaving open full time. Haven’t noticed a difference in performance and fixed my issue. Also check kick stand play.
 

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Fuel pressure is good..we cleaned the top injectors changed the air filter installed a brand new pump and regulator and still no luck 😢
Strap a mini bungee cord around your kick stand and go for a ride, aggressive riding could cause kick stand with worn springs to flop around and engage kill switch. Also, verify throttle body is fully opening during full throttle by gunning the engine in neutral with gas tank up and air box removed.
 

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I had the same problem around two years ago. When it hit 8,000 rpms does it cut out like you might be out of fuel. Thats what mine did and if I let of the throttle just a little and opened it back up it would take off like a rocket. I tried everything as well . And I showed no codes. I could not get it dynoed because of the problem. I wish I could tell you exactly what I did to fix it but I don't know what fixed it. I feel your pain. One thing I did do multiple times that I feel was a big factor in the turning point was clean the high pressure filter 3 or 4 times. I was able to get it dynoed . But I'm back in the same boat. I have no top end power . But I think it's timing and valve clearance. I'm struggling through my first valve adjustment and waiting on shims but I'm going to do a pressure test and Flo test tomorrow . And I think I'm going to do the high pressure filter by pass modification to eliminate problems with it down the road. I n my opinion its a bad design . At least you can change the filter if it gets dirty. There are some parts guys out there that will sell just the component that the high pressure filter sits in but I ca t remember wich one. I had one on order when the pandemic hit and they didn't know when it would come in so I cancelled it and got my money back and back flushed and cleaned my original the best I could. Hope your up and running soon . I will try and research my old emails and see if I can find the name of them if I can I will let you know
 
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