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Discussion Starter #1
So guys I recently picked my bike up from a friends where I have been storing it. It’s been sitting there for almost a year now. It ran fine before I took it there. Apparently he was starting it up every few weeks but I doubt it. Battery was dead. Went to jump and got it started no problem but as soon as I turned choke off it died. I noticed the bike was backfiring and choking up when the choke is on so I emptied all the gas out and which looked pretty nasty and I replaced it with fresh gas and some sea foam. Now the bike idles great with the choke on and Will drives around great if the choke is on but as soon as I turn the choke off it dies. What could be causing this issue? Can it be battery related considering I think it’s shot. Been charging it for two days on a trickle charger and it still won’t turn the bike over, it just clicks. The battery is putting out 12.5 volts. Or is this a different issue? I read online somewhere about someone having this issue and it was from the butterfly valve not opening up and it needed adjusted. This bike has sat quite often before in the past and never had issues. Thanks In advance
 

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Have you checked if your idle might be too low when choke is off causing it to stall...?
Fuel pump strainer might be clogged in your fuel pump...? Kawasaki brute force 700 fuel strainer is a perfect replacement if needed...!
Does your F.I dash light remain ON while the motor is running...?
Your valve clearance might needs to be checked..
Intake 0.10~0.15mm Exhaust 0.17~0.23mm
Your TPS/throttle positioning sensor might be out of range...see picture below...
 

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Discussion Starter #3
Have you checked if your idle might be too low when choke is off causing it to stall...?
Fuel pump strainer might be clogged in your fuel pump...? Kawasaki brute force 700 fuel strainer is a perfect replacement if needed...!
Does your F.I dash light remain ON while the motor is running...?
Your valve clearance might needs to be checked..
Intake 0.10~0.15mm Exhaust 0.17~0.23mm
Your TPS/throttle positioning sensor might be out of range...see picture below...
Have never had to mess with the idle so I doubt it is the problem and I already have turned it up a few clicks and it didn’t seem to help. I hate to keep turning it up and maybe cause other problems? I will check those other things tonight
 

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Discussion Starter #4
Have you checked if your idle might be too low when choke is off causing it to stall...?
Fuel pump strainer might be clogged in your fuel pump...? Kawasaki brute force 700 fuel strainer is a perfect replacement if needed...!
Does your F.I dash light remain ON while the motor is running...?
Your valve clearance might needs to be checked..
Intake 0.10~0.15mm Exhaust 0.17~0.23mm
Your TPS/throttle positioning sensor might be out of range...see picture below...
Ok so new battery didn’t fix it. If the FI light is the far left red light on the cluster then no it does not stay on. Only comes for a few seconds when you first turn the key on. I guess I need to look into the TPS
 

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Ok so new battery didn’t fix it. If the FI light is the far left red light on the cluster then no it does not stay on. Only comes for a few seconds when you first turn the key on. I guess I need to look into the TPS
If the TPS is in range...definitely check your valve clearance...
Intake 0.10~0.15mm Exhaust 0.17~0.23mm

Also low fuel pressure due to a clogged fuel strainer & low compression can cause your symptoms...!!
 

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Discussion Starter #6
If the TPS is in range...definitely check your valve clearance...
Intake 0.10~0.15mm Exhaust 0.17~0.23mm

Also low fuel pressure due to a clogged fuel strainer & low compression can cause your symptoms...!!
Looks like I need a special tool to check the tps according to that picture you sent me. Does that sound right?
 

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Ok so new battery didn’t fix it. If the FI light is the far left red light on the cluster then no it does not stay on. Only comes for a few seconds when you first turn the key on. I guess I need to look into the TPS
It's easier with the adapter..But you can stick the meter leads into the back of the TPS connector...Wires...Yellow positive & brown negative..see picture

Digital multimeter Only like the one pictured below

or adapter 57001-1538 Kawasaki 57001-1538 - SENSOR ADAPTER | eBay
 

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Discussion Starter #8
It's easier with the adapter..But you can stick the meter leads into the back of the TPS connector...Wires...Yellow positive & brown negative..see picture

Digital multimeter Only like the one pictured below

or adapter 57001-1538 Kawasaki 57001-1538 - SENSOR ADAPTER | eBay
Well I have Meter leads for using on moles plugs and could still not get dc voltage to it. I guess I will have to order the adapter. In the mean time I am gonna pull the fuel strainer and see if it’s clogged. I think I have a manual but in case I don’t how exactly do I do that?
 

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Discussion Starter #9
Fuel pump is out and I can’t really even see anything on it including the screen. According to the manual you can clean or check the filter or screen but you have to replace the whole assembly if clog is inspected. This seemed like waste of time Inless I’m missing something
 

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Discussion Starter #10
28102
28103

Ok so figured out how to get it apart on YouTube and found the strainer looking like this and it was half ripped off from the pump. Hoping this is my issue but I guess we will see. No matter what it needed replaced
 

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Discussion Starter #11
Have you checked if your idle might be too low when choke is off causing it to stall...?
Fuel pump strainer might be clogged in your fuel pump...? Kawasaki brute force 700 fuel strainer is a perfect replacement if needed...!
Does your F.I dash light remain ON while the motor is running...?
Your valve clearance might needs to be checked..
Intake 0.10~0.15mm Exhaust 0.17~0.23mm
Your TPS/throttle positioning sensor might be out of range...see picture below...
Fuel pump assembly has been cleaned, strainer and spark plug replaced. Still no luck. Guess I will buy that tool to read the dc Volts at the TPS
 

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Discussion Starter #12
I read online somewhere that a guy was having the same issue as me and he had to adjust the butterfly valve because it was completely closed. Can anyone leave me to the right direction on how to do this because I can’t find anything in the manual about it?
 

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I read online somewhere that a guy was having the same issue as me and he had to adjust the butterfly valve because it was completely closed. Can anyone leave me to the right direction on how to do this because I can’t find anything in the manual about it?
I forgot to ask you does your KFX have mods...upgraded Intake,cams exhaust ect... If yes, can you list them...
The butterfly & TPS calibration is set at the factory..If you mess with it & throw it out of calibration... you'll need a dynamometer to readjust the calibration or buy a new throttle body...!

Did you check your valve clearance or TPS voltage range... ???

Also do you have spark & is the fuel injector spraying fuel...???
 

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Discussion Starter #14
I forgot to ask you does your KFX have mods...upgraded Intake,cams exhaust ect... If yes, can you list them...
The butterfly & TPS calibration is set at the factory..If you mess with it & throw it out of calibration... you'll need a dynamometer to readjust the calibration or buy a new throttle body...!

Did you check your valve clearance or TPS voltage range... ???

Also do you have spark & is the fuel injector spraying fuel...???
Only engine performance mod I have is a empire full exhaust
I tried checking my tps voltage but could not get a reading with my meter so I’m still waiting for the adapter harness to come in from eBay
No I have not checked my valve clearances yet. I have never checked valves on anything so I had to order a gauge set and am waiting on them to come in still
And what do you mean do I have spark and fuel from the injector? I mean the bike runs with the choke knob pulled out so I definitely have it then but then it immediately dies when you push the knob in so there is definitely no spark or fuel there.
I ask about the butterfly valve being open because it would make since. Choke on no issues as soon as you close it it completely closes it off Inless you are giving it throttle which would keep it open
 

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Discussion Starter #16
Have you tried cracking throttle then and shutting choke off?
Yes if I barely crack the throttle with the choke off then it runs
 

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Sounds to me like you may be onto your problem. Anyway of reaching out to the guy you mentioned that adjusted his? What about inquiring about having a dealership perform the service?
 

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Only engine performance mod I have is a empire full exhaust
I tried checking my tps voltage but could not get a reading with my meter so I’m still waiting for the adapter harness to come in from eBay
No I have not checked my valve clearances yet. I have never checked valves on anything so I had to order a gauge set and am waiting on them to come in still
And what do you mean do I have spark and fuel from the injector? I mean the bike runs with the choke knob pulled out so I definitely have it then but then it immediately dies when you push the knob in so there is definitely no spark or fuel there.
I ask about the butterfly valve being open because it would make since. Choke on no issues as soon as you close it it completely closes it off Inless you are giving it throttle which would keep it open
Yes the butterfly is calibrated to the throttle positioning sensor to control the advance ignition timing & fuel injector spray...

Your symptom sounds like too low of piston compression, fuel flooding your motor with the choke ON provides a temporary seal at the point of leakage for enough compression to run, turn off the choke no more fuel seal & the compression falls, valve clearance is the usual suspect
Cylinder Compression Service Range: 49.0 ∼ 81.8 psi) @900 r/min (rpm)
 

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Discussion Starter #19
Sounds to me like you may be onto your problem. Anyway of reaching out to the guy you mentioned that adjusted his? What about inquiring about having a dealership perform the service?
Here is the link to the post I found. Unfortunately it’s from 07 and idk how I would find the guy and it sounds like an issue from the dealer but I do think i have a similar issue
 

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If I were in your shoes I’d try @Dust Devil recommendation. I have lurked on the website a lot and he always gives sound advice. Checking valves costs no money and is a great place to start. If you find that’s not the problem maybe inquire what a dealership would charge to check your butterfly.
 
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