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Discussion Starter #1
Curious if anyone else has had to replace their fast idle solenoid? I am having a cold start only issue with my 2019 Monkey that lends me to beleive this part may be the problem. Idles like crap then dies. Start it a second time and it will stumble then level off. Idles and runs fine when warm.

I come for the era of carbs, and this is the first FI bike I have ever had any issue with.

I have done all of the following to correct to no avail:

Reset ECU
Reset TPS
Fresh Fuel
New spark plug

Only mod is a Takagawa STD exhaust. (No leaks). Bike has 220 miles

Any help is greatly appreciated.
 

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2020 Honda Grom
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You might try raising the idle by a couple hundred rpm. There is a black plastic screw with a spring behind it on the throttle body, give it 1/4 turn further open and see if it helps. Easy to put it back where it was if it doesn't.
 

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Discussion Starter #3
Ordered a new solenoid and an EOT sensor.

I will advise everyone what happens. I was a little shocked that, per the manual, a bad EOT sensor can effect the idle.

A carb on this little bike doesn't sound half bad right now. No sensors, no fuel pump, add a jet kit and done.
 

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I know how you feel as F. I. is a whole new ballgame for me, too. I've never gotten 113-127 MPG out of a similar 125 with a carburetor so there may be something to this newfangled technology.
 

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Discussion Starter #5
Update - I found that if I wait about 30 seconds, from the moment the fuel pump stops running, after turning the key on to to press the start button, the bike fires up much better and second start is not required.

It really never has 'Fast Idled" like if on a choke, so I am still convinced that the fast idle solenoid may have something to do with the issue.

Does anyone else notice a 'Faster Idle" with their bikeswhen starting cold?

I'm going to do a little "Throttle Therapy" after adding some Techron to the fuel.

I'll let everyone know how that works out.
 

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2020 Honda Grom
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My oem and CJR flashed ecu both idled faster/louder when cold. Did you ever determine your idle rpm?
 

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Mine has fast idle on first start up but not all the time, bike must use one of the temp sensors to determine if it’s needed or not
 

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Discussion Starter #8
Just ordered a Tach,. She idles great when hot. Idle has never been fast when cold.

New fast idle solenoid and an EOT sensor on order.
 

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Discussion Starter #9
Update - Bumped up the idle a bit, "Plastic" (Really) screw was very easy to turn, seemed loose. I guess I am just used to the brass ones on carbs.

Idle seems too high to me now, but I know the FI bikes like a higher idle.

We'll see what a cold start brings in the AM
 
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