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Discussion Starter #1
Alright guys i posted before in 2017, im having the same prob just getting around to it again. MY 08 KFX keeps bogging down after riding for 10-20 min. Charged the batt, changed the ignition coil. Which i thought it was. The fan wont turn on before it bogs down. It turns on when i unplugg the temp sensor plug, but then it wont start and smells lole flooding. Any thoughts please?
 

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Discussion Starter #2
Ok, so i rode it around till it started bogging, came home, took off the water temp sensor plug, it started while hot, but doesn't start with it cold unplugged. It ran awesome, i took it out again and it didnt bog out, f.i like was on the whole time though, and it backfired once in a while but other than that i think its the water temp sensor, unless anyone else has a clue before i buy another one?

P.s I live right by the desert so i just ride from my house to the trails, so from bogging and unplugging the wts to back to riding was like 2 min
 

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There is a way to test it! But i can’t remember the exact procure.

It honestly sounds like a water temp sensor
 

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Discussion Starter #5
Also, if i ride it with the water temp sensor unplugged until i get a new one, will that hurt anything?
 

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The water temp sensor is part of fan control and fueling.

The fan will in the whole time. I can’t remember if it changes the fuel mixture
 

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Is that a yes or no, on riding with it unplugged haha.
Is your KFX all stock or has mods...???? fuel controller,upgraded intake, full exhaust...ect...?

Unplugging your water temp sensor should cause your F.I dash light & fan to come ON...

The water temp sensor needs to be plugged in or the DFI goes into limp mode & locks your advance timing....

To test the water temp sensor...see picture below...

lean fuel mixture or Low fuel pressure...can cause your symptoms...!
 

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Discussion Starter #9
All its got is a jardine rt99 exhaust and a notoil with airbox lid off. I rode around the other day with the water temp sensor unplugged. It did last longer before it bogged out, but itbl still did the same thing.
 

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All its got is a jardine rt99 exhaust and a notoil with airbox lid off. I rode around the other day with the water temp sensor unplugged. It did last longer before it bogged out, but itbl still did the same thing.
Keep the water temp sensor PLUGGED IN...!!!

Check your fuel pressure 43 psi (idle to full throttle)...tester... https://www.ebay.com/itm/Fuel-Injection-Pump-Injector-Tester-Test-Pressure-Gauge-Gasoline-Cars-Trucks-Kit/122271091503?hash=item1c77eccb2f:g:LdcAAOSwfl1chyt6

Also check your valve lash/clearance....

Valve Clearance: between cam and valve lifter
Standard:
Exhaust 0.17 ∼ 0.22 mm (0.0067 ∼ 0.0087 in.)
Inlet 0.10 ∼ 0.15 mm (0.0039 ∼ 0.0059 in.)

If the valve clearance is not within the specified range,
adjust it.
 

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Dust devil, you think it could still be my water temp sensor?
It could be a faulty water temp sensor, faulty spark plug cap, low fuel pressure, valves clearance & dirty injector nozzle...Don't know...?

Also check your valve lash/clearance....

Valve Clearance: between cam and valve lifter
Standard:
Exhaust 0.17 ∼ 0.22 mm (0.0067 ∼ 0.0087 in.)
Inlet 0.10 ∼ 0.15 mm (0.0039 ∼ 0.0059 in.)

If the valve clearance is not within the specified range,
adjust it.
 
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