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Idle Idle fluctuating

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Old May 12, 2019 | 08:47 AM
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Default Idle Idle fluctuating

2019 Street Glide Special, just over 600 miles. At idle it is flucuating. Anyone else experiance this issue?
 
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Old May 12, 2019 | 08:51 AM
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Check to see if your EITMS is enabled.
 
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Old May 12, 2019 | 09:18 AM
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Originally Posted by Throttle1971
2019 Street Glide Special, just over 600 miles. At idle it is flucuating. Anyone else experiance this issue?
Your first Harley? Harley's "hunt" at idle. Post a video so we can understand what you're experiencing.
 
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Old May 12, 2019 | 09:26 AM
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Originally Posted by 702
Check to see if your EITMS is enabled.
No. Actually when EITMS kicks in, the motor runs smoother.

OP: the M8s have an erratic idle.
 
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Old May 12, 2019 | 09:57 AM
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As long as it’s within a couple hundred rpm it’s normal. Any M8 I’ve seen is bouncing around between 700-900.
 
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Old May 12, 2019 | 10:02 AM
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Originally Posted by Throttle1971
2019 Street Glide Special, just over 600 miles. At idle it is flucuating. Anyone else experiance this issue?
I have a '19 Road Glide 107 stock. The idle definitely seems to bounce around. The FSM specs idle rpm at 850 but doesn't give a tolerance. I recall the twin cam had a + or - 50 rpm on the idle spec). Watching the tach at idle it does appear to drop below 850. Without a tuner it's impossible see what it's really idling at.... Bike runs great, I'm not worried about the idle.
 
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Old May 12, 2019 | 10:57 AM
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Cool tuner needed ...

you'll need a tuner like power vision to see all the setting/tables and to be able to adjust anything ...what we have found is that the stock maps have the
'Idle Spark Control Max" table set too high at 10-12 degrees and the
'idle Spark Control Gain" table set too high at 6-8 degrees...
what is happening is the ECU is trying to control the idle by adding and subtracting ignition timing ...but in a too large of a range ...causing the fluctuation...
what we do is lower both tables ....set the Max Table at 2 and the Gain Table at 1 ...
we see a dramatic increase in the stability of the idle ...with the narrow range ...there is much better control ...
hope this helps ...
good luck ...


 
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Old May 12, 2019 | 11:44 AM
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You need to state how much. I would say my m8 idle bounces around more than my twin cam but I am also looking at a digital readout vs analog on the twin cam. I posted before about a roblem with startup idle,had some warranty work done, problem still there of it going too lean and back to normal. Unusual but it is now back to normal and I have no idea why? Have a few ideas but nothing I can prove but happy to not.be stalling out on startup.
 
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Old May 12, 2019 | 11:57 AM
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Hey Springers4ever....got a question for you since you've seen the stock tunes....my 2019 Road Glide rpm always shoots to 2400 the second it fires up... It drops right down in a couple seconds to a normal cold idle (around 1200 or so). It definitely shoots to 2400 with EVERY start. I'm in FL and don't ride below 70 deg so it can't be a cold weather setting. Is there something in the tune you've seen that will cause this?

thanks
 
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Old May 12, 2019 | 01:31 PM
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Originally Posted by Stickman53
Hey Springers4ever....got a question for you since you've seen the stock tunes....my 2019 Road Glide rpm always shoots to 2400 the second it fires up... It drops right down in a couple seconds to a normal cold idle (around 1200 or so). It definitely shoots to 2400 with EVERY start. I'm in FL and don't ride below 70 deg so it can't be a cold weather setting. Is there something in the tune you've seen that will cause this?

thanks
That is controlled by the IAC Crank to Run table. Lower the values if you have a tuner that allows it. Note the description in the lower right.


 

Last edited by VDeuce; May 12, 2019 at 01:34 PM.
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