M8 problems
Cruiser
Joined: Aug 2013
Posts: 220
Likes: 64
From: The Netherlands
Problems starting here as well...
Wanted to go for a ride, but when I started the engine a terrible scraping noise was all what happened
Not sure how this works, but it sounds like the starter motor is turning around but "somewhere" some sprockets are not connected the way they should be.
Motor will be picked up by dealer next week; worst thing is: it's finally spring here with temps of mid 20's C
Wanted to go for a ride, but when I started the engine a terrible scraping noise was all what happened
Not sure how this works, but it sounds like the starter motor is turning around but "somewhere" some sprockets are not connected the way they should be.
Motor will be picked up by dealer next week; worst thing is: it's finally spring here with temps of mid 20's C
Advanced
Joined: Apr 2018
Posts: 57
Likes: 14
From: NJ
Excellent.
I think the PO151c code is the rear O2 sensor low (or lean). Maybe from the new slip-ons. I'm just concerned because it is setting off the check engine light. Maybe there is an exhaust leak. I'll check the clamp later.
I think the PO151c code is the rear O2 sensor low (or lean). Maybe from the new slip-ons. I'm just concerned because it is setting off the check engine light. Maybe there is an exhaust leak. I'll check the clamp later.
Last edited by almico; May 5, 2018 at 08:46 AM.
Outstanding HDF Member
Joined: Aug 2012
Posts: 2,442
Likes: 418
From: South Carolina
Finally got someone at the dealership (service manager) to agree that the noises coming from my engine weren’t normal. He shot some video and sent it to the Mothership and they gave him the go ahead to open it up and see what the culprit is. I’m at 3,100 miles and it’s been mondo noisy since day 1. On the test ride, at delivery, at the 1K, and every time I was by the dealer...”my bike is WAY too noisy”. “They all do that...it’ll settle in...that’s normal on the 117...”. Etc, etc, etc.
I never had slumping issues or overheating or detonation or any other problems, just a random loud clacking coming from inside the mill. Doesn’t sound like lifter clatter or anything. It’s in the shop now for open-heart surgery, should know something by early next week.
I never had slumping issues or overheating or detonation or any other problems, just a random loud clacking coming from inside the mill. Doesn’t sound like lifter clatter or anything. It’s in the shop now for open-heart surgery, should know something by early next week.
Road Captain
Joined: Apr 2007
Posts: 679
Likes: 120
From: Fairbanks, AK.
There's some earlier talk either here or on the HD Tech forum about reversion flow into a more open exhaust outlet causing O2 sensor issues. Under certain conditions (like closed throttle with the rpms up?) air can get sucked into the muffler outlet and unburned oxygen fools the sensor into thinking lean and causing low output voltage. Throws a code. Can happen during periods of open valve overlap. Hold a piece of paper near the muffler outlet and rev the engine up then close the throttle, The paper can get sucked flat against the outlet when the throttle is closed. Might be something else tho.
Road Master
Joined: Sep 2014
Posts: 779
Likes: 29
From: AMERICA
Their job is to tell you no problems. They want to keep getting a paycheck. Forum members are telling you there is a problem. There is a problem.
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Seasoned HDF Member
Joined: Dec 2005
Posts: 19,925
Likes: 8,027
From: poway
There's some earlier talk either here or on the HD Tech forum about reversion flow into a more open exhaust outlet causing O2 sensor issues. Under certain conditions (like closed throttle with the rpms up?) air can get sucked into the muffler outlet and unburned oxygen fools the sensor into thinking lean and causing low output voltage. Throws a code. Can happen during periods of open valve overlap. Hold a piece of paper near the muffler outlet and rev the engine up then close the throttle, The paper can get sucked flat against the outlet when the throttle is closed. Might be something else tho.
They were talking about decatted head pipes on twin cams.. Look at the O2 sensor location on a M8.
Seasoned HDF Member
Joined: Dec 2005
Posts: 19,925
Likes: 8,027
From: poway
Only problem I see is the chicken little syndrome.