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Monkey bad idle and low speed bogging

6K views 4 replies 2 participants last post by  Old1Eye 
#1 ·


So I have had this issue once when the bike was stock, and it went away on its own.

4 months later, it's not stock now for a few months and it's back again.

So, it won't idle properly when it's warmed up, keeps dropping off and then picking up again just before it stalls, and when cruising along at low throttle it does the same to the point I stop going towards until I wack the throttle open.
Which in low traffic speeds makes me kangaroo, and isn't safe or fun.

I have reset the ECU and TPS but no difference.
The spark is fine, cleaned the airfilter and checked there is no air leaks.
Exhaust is fine too, did the valves about 1000km ago.
Oil was the same time too.

I have fitted new exhaust, air intake system, Efie device a couple of months ago and it's has been running fine until last week.

Spark plug is a good light tea colour.

I'm at a loss as to what this is?

Oh and I'm not going back to the dealer, as every time I have it comes back in a worse state, even had it back once and it was covered in oil and leakin,and the bolts for the top fork brace were missing.
 
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#2 ·
Sounds like the fuel trims are going too lean then too rich as you can hear it change pitch, as if it's not really leveling out as it should.
What is your black air screw set to located on the side of the throttle body? I believe 2 turns out is starting point.
Where is your IAT sensor located?
What is your EFIE set to voltage wise?
 
#3 ·
Sounds like the fuel trims are going too lean then too rich as you can hear it change pitch, as if it's not really leveling out as it should.
What is your black air screw set to located on the side of the throttle body? I believe 2 turns out is starting point.
Where is your IAT sensor located?
What is your EFIE set to voltage wise?
IAT sensor?

Air mix screw is set to two turns out, and efie was set to .210 for 4000km.
Then this started happening and it suddenly got super rich on the plug, so dropped it to .180.
Same issue, so
150.
Same issue, so
Removed efie.
Still same issue running rich on the plug.

New clean plug each time, and bogging and idle issue continued
 
#4 ·
If the IAT (intake air temp sensor) were to be resting on the engine or getting abnormal heat it can cause afr to jump. As long as it's zip tied up high or away from engine heat should be fine.
Possibly a bad o2 sensor giving false readings
 
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