rough idle on m8
Club Member
Joined: Mar 2009
Posts: 66,131
Likes: 51,462
From: Niles Canyon Ca.
Idle getting erratic is how I know my clutch safety switch is flaking out again, so far a drop of lube on the plunger has cleared the issue up for several months before needing it again. Try starting the bike in gear, it won't the switch is funky.
Road Captain
Joined: Jul 2011
Posts: 522
Likes: 204
From: dunedin, fl
been there, done that! it's the clutch safety switch. I had 3 replaced before they got one to work. Harley redesigned it and there's a service bulletin on it. fanning clutch in traffic at bike week almost got me killed, the thing was reaching and loping. it may or may not start in gear, or be intermitttent. tell dealer it is a safety issue, it will wake him up and he will replace the switch.
Novice
Joined: Jun 2018
Posts: 24
Likes: 2
From: Santa Clara
I will try and see if it starts with the clutch pulled in and in gear but last time it stalled I tryed to restart while rolling in gear would not restart until I stop in put bike in neutral
Road Master
Joined: Jan 2016
Posts: 1,143
Likes: 433
From: Menifee, CA
I struggled with erratic idle for the first 3k miles on my new 2018 RGU. It never actually died on me, but it came real close, and at times was a serious distraction when taxiing a parking lot, especially with my pax on-board.
Once I learnt it was being caused by the clutch switch, I took bike to dealer shop, found out HD has a new re-designed switchback and lever assys, got them replaced, and it has been perfect ever since.
Erratic idle is apparently first signal of clutch switch problems. Also, inability to start the motor in-gear with clutch lever pulled. It will probably be intermittent. It will come and go. Sometimes it will start in-gear, other times not.
The service writer didn't even look at the bike. I described the issue symptoms, and he replaced the clutch switchback and lever.
Once I learnt it was being caused by the clutch switch, I took bike to dealer shop, found out HD has a new re-designed switchback and lever assys, got them replaced, and it has been perfect ever since.
Erratic idle is apparently first signal of clutch switch problems. Also, inability to start the motor in-gear with clutch lever pulled. It will probably be intermittent. It will come and go. Sometimes it will start in-gear, other times not.
The service writer didn't even look at the bike. I described the issue symptoms, and he replaced the clutch switchback and lever.
Club Member
Joined: Mar 2009
Posts: 66,131
Likes: 51,462
From: Niles Canyon Ca.
Clutch switch is funky and that's your idle problem. Have no clue how or why they are related but it is.
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Road Warrior
Joined: Apr 2007
Posts: 1,382
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From: Illinois
That switch is connected to the ECM via canbus, so who knows what the ECM does with it.
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Joined: Mar 2006
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Lon