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CVO Technical => Milwaukee-Eight => Topic started by: 1roadking on May 15, 2020, 12:14:13 AM

Title: Engine vibration 2020 M8 117
Post by: 1roadking on May 15, 2020, 12:14:13 AM
I feel like the vibration at idle is way better on my 117 M8 but I feel more vibration at speed then the twin cam. It’s mostly in the floor boards. It’s not terrible but very noticeable. Is this common?
Title: Re: Engine vibration 2020 M8 117
Post by: Phreakyz on May 15, 2020, 05:57:23 AM
Vibration at Engine speed or Vehicle speed?   If while sitting still,  you bring the throttle up, do you feel the vibration or only when moving at speeds?    If when moving, then could be a tire/balance issue? 
Title: Re: Engine vibration 2020 M8 117
Post by: FLSTFI Dave on May 15, 2020, 06:19:54 AM
Loose or improperly adjusted motor mount could also be the issue. 
Title: Re: Engine vibration 2020 M8 117
Post by: 1roadking on May 15, 2020, 07:05:40 AM
Can you guys feel any vibration in your floor boards. I might just be being picky but it’s at least if not more noticeable then my twin cam built 117. I was expecting it to be smoother given the Motor is counter balanced and rubber mounted.
Title: Re: Engine vibration 2020 M8 117
Post by: mark on May 15, 2020, 08:38:39 AM
When you feel the vibration and pull in the clutch, does the vibration disappear?  If so, it’s not a tire balance problem.  Might try loosening the floorboard bolts (just enough for the floorboard to move up/down freely by hand). 
Title: Re: Engine vibration 2020 M8 117
Post by: Phreakyz on May 15, 2020, 09:12:23 AM
Can you guys feel any vibration in your floor boards. I might just be being picky but it’s at least if not more noticeable then my twin cam built 117. I was expecting it to be smoother given the Motor is counter balanced and rubber mounted.
Check out this old thread...

https://www.cvoharley.com/smf/index.php?topic=117419.msg1481912#msg1481912
Title: Re: Engine vibration 2020 M8 117
Post by: grc on May 15, 2020, 09:28:54 AM

Harley supposedly set up the counter-balancer system to leave some engine vibration at idle to appeal to old time Harley riders.  I'm not sure I really believe that hogwash, it's probably more like their system is only effective in a certain range of rpm and they chose higher rpm smoothness over idle smoothness.  Seems like a reasonable choice to me.  However, 1roadking's issue seems to be the opposite, vibration OK at idle and more apparent at higher speeds. 

1.  Ride the bike at the speed and rpm range where the vibration is most apparent, quickly pull the clutch lever and chop the throttle.  If the vibration remains, it's not the engine.

2.  Run the engine at the rpm where vibration is most apparent while sitting still with the clutch disengaged.  See if you get the same vibration as what you feel when riding at that rpm.  If so, and it didn't do this before, I'd be inclined to check for motor mount binding issues before assuming anything internal.

3.  When in doubt, have your dealer let you ride other similar bikes to see if what you are feeling on your bike is also evident on other 117's.

JMHO - Jerry
Title: Re: Engine vibration 2020 M8 117
Post by: 1roadking on May 31, 2020, 08:27:52 PM
Ok, so I tried my friends 2020 CVO and his definitely has less vibration, it still has it but probably half as much. . It vibrates in neutral sitting still at same RPMS but I feel it more when actually riding. I also noticed it’s way more prevalent at cruising speed and When engine breaking or decelerating. Under hard throttle I don’t feel it as much if any. I’m thinking it’s a motor mount/alignment issue as the motor itself seems to not vibrate Anymore then my friends bike.  It’s primarily felt in the foot boards. Any thoughts?