Engine Shake Riddle
Extreme HDF Member
Joined: Sep 2010
Posts: 14,744
Likes: 402
From: Phoenix '53, '88, '09 Big Twins
as touched on above:
the counter balancing is a parasitic load on power, adding complexity to the lubrication, drive and bearings- any of which go wrong and pooch the motor.
the "rubbermount motor"- is actually the entire drivetrain, primary drive, clutch and tranny- the mount system adds the to overall height and will not fit the softail frame with out changing the entire concept of the styling.
The rubber mount system also robs some power- some forward motion is lost to the bushings.
as for comfort, some are fine with the solid mount buzzing along at speed- esp the pan/shovel/evo
but for all day operation the rubber mount bikes are more popular, the motor really only shakes at idle. stay off the front brake at a stop and the rider will notice it even less
mike
the counter balancing is a parasitic load on power, adding complexity to the lubrication, drive and bearings- any of which go wrong and pooch the motor.
the "rubbermount motor"- is actually the entire drivetrain, primary drive, clutch and tranny- the mount system adds the to overall height and will not fit the softail frame with out changing the entire concept of the styling.
The rubber mount system also robs some power- some forward motion is lost to the bushings.
as for comfort, some are fine with the solid mount buzzing along at speed- esp the pan/shovel/evo
but for all day operation the rubber mount bikes are more popular, the motor really only shakes at idle. stay off the front brake at a stop and the rider will notice it even less
mike
Road Captain
Joined: Jan 2012
Posts: 621
Likes: 3
From: N CA
I think HD took a survey a few years back & they found this is what the owners wanted - they didn't want the balanced engine in the touring - My Ultra Classic is pretty smooth at speed, not as smooth as a GoldWing but what is - I think the Shake is just part of the Harley charm - not so sure a shake that bad is good for any engine but it is what it is - tom
Road Captain
Joined: May 2009
Posts: 505
Likes: 2
The B engine came out a year after the standard (rubber mount) 88 engine because they had to design and build the counterbalanced system for it. The reason the softail motor is solid mounted is because it enabled the bike stylists to wrap the frame around the engine a lot closer than with a rubber mount system to give a "neater" more custom look. It makes less power but vibrates less at idle. It's not smoother once your feet are on the pegs.
Road Warrior
Joined: Oct 2006
Posts: 1,916
Likes: 0
From: San Antonio, Texas
I like the shake and wouldn't want a "smooth" idling Harley. My EG is smooth at speed, which is all I care about. The ONLY thing I don't like about the rubber mounting is the fact the stupid oil filter is right on top of the front mount, but that's another story...
Seasoned HDF Member
Joined: Mar 2009
Posts: 24,778
Likes: 9,366
From: Snow Hill, NC
I used a loaner Heritage from the dealer last year and found out quickly at 70 mph what they meant.... it goes through the handlebars... I will stick with the rubber mounted for trips... i might buy a Softy for local rides or for the wife after a few years on the FXDP ...
HD Forum Stories
The Best of Harley-Davidson for Lifelong Riders
Jason Momoa Is Turning Classic Harleys Into PHEVs
Verdad Gallardo
Harley-Davidson Fat Boy Becomes a Dark, Decepticon-Inspired Custom
Verdad Gallardo
6 Weirdest Harley-Davidsons Ever Sold to the Public
Verdad Gallardo
7 Times Harley-Davidson Chucked Tradition Out the Window
Verdad Gallardo
7 Surprising Harley-Davidson Products that Are Not Motorcycles
Verdad Gallardo
8 Best Harley-Davidson Motorcycles Ever
Pouria Savadkouei
10 Worst Harley-Davidson Motorcycles Ever
Pouria Savadkouei
Killer Custom's Jail Break Is The Breakout That Refused to Blend In
Verdad Gallardo
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?
Verdad Gallardo
Thread
Thread Starter
Forum
Replies
Last Post
Flufebunekilr
Touring Models
61
May 1, 2026 08:07 PM