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Bogging and not running right

Athosch97

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Hello everyone hope I find you all well and ready for the holidays! Today I have a weird one, The bike was running just fine we went on the mountains rode around 300-400kms I had noticed that the bike was kind of weird, but nothing special.
Came back home parked the bike thought it was just my idea. Next day I hop on the bike to go refuel and go for a night ride,(the bike wouldn't run right) Got to the gas station turned off the bike filled it up, and it wouldn't start. I was there around 20 minutes trying to figure out what happened but nothing, It would crank just fine but wouldn't start. Pushed the bike home (it was not fun). Once I came home I messed around with the air screws and the bike started but wouldn't run right at all again. Today I changed the spark plugs (new irridium ones) but nothing has changed, Took off the fuel pump relay cleaned everything put back together again, still nothing. Would love some suggestions.


 
Sounds like it's starving for fuel. Could be the fuel pump is failing. Could be the fuel filter is clogged.
It could also be the (TPS) throttle control sensor. You can look at the TPS through the diagnostics to see if it's skipping. IIRC the values for the TPS are 16 to 100.
 
Sounds like it's starving for fuel. Could be the fuel pump is failing. Could be the fuel filter is clogged.
It could also be the (TPS) throttle control sensor. You can look at the TPS through the diagnostics to see if it's skipping. IIRC the values for the TPS are 16 to 100.
I forgot to mention that I have already cleaned the fuel pump filter (as much as i could ofcourse).

TPS Values are 14-99 Not skipping any numbers.

I was thinking of removing the injectors tomorrow morning to do some cleaning see if it makes any difference.

How can I see if the fuel pump is failing? Thanks for the reply!
 
I forgot to mention that I have already cleaned the fuel pump filter (as much as i could ofcourse).

TPS Values are 14-99 Not skipping any numbers.

I was thinking of removing the injectors tomorrow morning to do some cleaning see if it makes any difference.

How can I see if the fuel pump is failing? Thanks for the reply!
I think the fuel pressure is supposed to be 36 psi. If some other member can confirm? @TownsendsFJR1300 @Gary in NJ
 
The fuel pressure is 36psi.

What do mean by “I messed around with the fuel screws”? Do you mean the throttle body sync screws? If that’s the case you made the problem worse.

I would always suggest the classic diagnostic method; check for spark, fuel, air and then compression. For example rather than changing the spark plugs, simply check for spark.

The bogging in the video could be a symptom of the throttle bodies being out of sync.
 
What do mean by “I messed around with the fuel screws”? Do you mean the throttle body sync screws? If that’s the case you made the problem worse.

Unfortunately yes. Alright, I know how to check for spark and compression. But I need some guidance with the fuel (how do I check the psi?) and air, By air you mean checking if any of the hoses / vaccum going to the airbox is fine?

Sorry if my questions are dumb I'm just not very familiar with mechanical stuff, learning as I go.
 
At this point I think the throttle synchronizing being out now is the lesser of the issue and you need to establish you are getting the proper amount of fuel. You need a fuel pressure gauge to establish you're getting 36 psi. You could see 36 psi from the pump but when you open the throttle and the ecu increases fuel injection the fuel pressure can not drop any significant amount. If it does drop you're not getting enough volume of fuel delivery.
 
Greetings everyone I am back to this issue but now with more awareness, I have found the culprit (unfortunately after replacing a fuel pump) The O-ring after the pressure regulator seems to be either worn out or not the original I don't have any photos of it because after spotting it I quickly reassembled it after I properly seated it and the proceeded to test the bike, after that the bike run just fine. Now after 150km of riding again the same issue it started slightly bogging on low rpms which tells me that O-ring has moved again. Now I'm here asking for any photos of anyone who has disassembled his own fuel pump I would like to see if the one I have is the correct dimensions or if it's changed. Thanks in advance!

1759825277428.webp
 
If you don't have a source in your area for "O" rings you might take some measurements to get an idea of what you need. The inner diameter and outer diameter would probably be a good dimension. If you don't have a source maybe I could mail you what you need. I have an over the top commercial hardware supply that has every size I've ever needed.
 
Adding another picture i found on youtube. The O-ring that sits right there where I've circled.
Have a look at all 3 pictures here in case it is getting cockeyed when re-assembled:
 
Goodmorning everyone! Appreciate the help Motogiro! No need to send I will go out for hunting now that I've seen the pictures sent from Tuning-forks I can see that the O-ring I have slotted on is indeed the OEM one, which means it's most probably flattened.

At least now I have a spare OEM fuel pump laying around!! lol
 
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