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Discussion Starter #1
hello everyone i have just recently started to have this issue with my current set up on my kfx it seems to keep fouling plugs and is very hard start with and with out the choke knob out it cranks for a while and alot of the time it just wont start i pull the plug and it is always black and fouled sometimes a little wet ive even leaned out my programmer a little and still the same i even tried it with out the programmer but really didnt ride it much ive had this for a while and the issue just recently started
 

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If it recently started, then you might have a water temp sensor going bad....??

Is your F.I dash light remain on when starting...???

Have you checked your TPS voltage...? 0.58~0.62 volts @ close throttle
 

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Discussion Starter #4
i have not yet checked the tpms and no there is no FI light on at all i even checked to find codes but there was none
 

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Discussion Starter #5
i just checked tpms voltage everything is good there i pulled the plug and its slightly wet is there a chance its getting oil fouled ?? maybe im using to much oil or somehing?
 

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Whats the color of your exhaust smoke...

oil = blueish/white smoke
fuel = black smoke...

If the valve lash is in spec, intake 0.10~0.15mm exhaust 0.17~0.23mm and compression is good 63~68 psi throttle closed...

And If it's fuel fouling than test or just replace your water temp sensor, when your temp sensor goes bad it will enrich your mixture and even flood it...

Water temp sensor is on the back of the cylinder under the throttle body...
 

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Check compression.

Change your coolant temp sensor.
 

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Discussion Starter #10
Compression is good its more gas fouled im gonna try the temp sensor
 

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Compression is good its more gas fouled im gonna try the temp sensor
Yeah, the list ain't real long on this stuff it if is on the fuel side.

Injector spray
Fuel controller
Ignition coil, wire or boot (weak spark)

Sensor reading out causing too much fuel delivery.

Most common to show up in cold weather are the temp sensors. Hard to crank cold, and runs bad/rich/cold.... or starts well cold and floods out as it warms up.
 

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Ive ran into this same issue, local bike shop said it could even need a top end....is this ALSO a possibility?
Welcome to the Forum...!
Yes...depending on the type of fouling...?
oil fouling...bad rings/scuffed cylinder wall or bad valve seals
Fuel fouling...bad water temp sensor/ improper fuel tune with fuel controller...
 

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Also; my kfx has been running only on 91 and 95 it's whole life, I bought it, now runs on 98, can running 98 for its first time have an affect on anything?
 

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Also; my kfx has been running only on 91 and 95 it's whole life, I bought it, now runs on 98, can running 98 for its first time have an affect on anything?
Not really...What is your piston compression...?
Stock piston is 12.0:1 requiring 91 octane...
Piston of 13.0:1 requires 98~105 octane

What type of plug fouling are you experiencing oil or fuel...
Black exhaust smoke is fuel
Blueish white exhaust smoke is oil
 
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