I have seen a post regarding checking the engine rubber mounts , something about undoing the bolts and fitting washers to stop the stress?
Can anyone help me find this post!
Thanks
Scouser

 

I've read the thread you are talking about, but haven't really looked for it. It had to do with shimming the front motor mount to reduce the amount of engine vibration. Some say it is an improvement. I've never done it bacause I just accept the vibration as a known given with harleys.

Hope this helps....

Best wishes....Tim(HT)

 

Take a look at this:

I would do the chassis / engine alignment procedure, as well as shimming the mount (see below).


Quote:
Originally Posted by WS6 Formula
Having the engine mount preloaded from the factory is most likely the cause of engine mount failures. When I removed my vapor canister my frame mount pulled forward and the engine mount also pulled away into a stress free condition. I had a jack under the engine so that I could screw the bolts in by hand with no resistance which gave me a 3/8" gap that I shimmed with washers. Then I came across the below post and it seems to be a common problem on rubber mounted bikes.

Quote:
FXD Vibration Problem Cured - $10 Materials

Sorry for the long post, but I have cured my Dyna's vibration problem for about $10 in materials and I thought others might benefit from my approach.

I have a 2005 FXDI with a HD 95 inch Stage I kit.

Like some others on the Forum, my bike had, what I consider, excessive engine vibration transmitted to the handlebar, foot pegs, and seat. The vibration was especially evident below 3000 rpm. At idle, the handlebars jumped around excessively.

I followed the Service Manual procedure for vehicle alignment in an attempt to reduce the vibration. Alignment includes loosening (but NOT removing) ALL the motor mount attachment bolts, and then running the motor for 5 seconds during which allow the mounts to align themselves to the frame. The motor mount attachment bolts are then re-torqued to spec. The procedure helped a little, but did not cure the problem. I also looked at other changes that might address the vibration problem such as a Bar Snake, different length handlebars, handlebar mount bushings, etc. All these are Band-Aids on the fundamental problem of too much vibration.

A few weeks later I was thinking about the motor mounts and the alignment procedure and was struck by the cause/cure of the vibration problem. Any elastic motor mount, like the Dyna's, has a limit to how much vibration it can absorb. Engine movement in excess of this limit is transmitted through the frame to the handlebars, foot pegs, seat, etc as vibration.

What struck me was that when I did the alignment procedure and the mounting bolts were LOOSE, there was a gap between the mount and the frame. Tightening the mounting bolts caused my front motor mount to be PULLED forward to the frame as the mounting bolts were tightened. I noticed that when the mounting bolts were torqued, the frame was also deflected somewhat.

THE ELASTIC TRAVEL OF MY MOTOR MOUNTS WAS LARGELY USED UP JUST BY BOLTING THE MOTOR MOUNT TO THE FRAME.

Any movement of the motor would not be absorbed by the mount as the elasticity of the mount is already used up before the motor is even started. Hence any engine movement is transmitted to the frame and is felt as a vibration. This would also explain premature failure of Dyna motor mounts as they are under stress to begin with.

My solution was to shim the gap between the UNSTRESSED front motor mount and the frame. THE ENTIRE INHERENT ELASTICITY OF THE MOUNTS IS NOW AVAILABLE TO ABSORB ENGINE MOTION. MY VIBRATION PROBLEM WAS GONE!

EDIT ---------

Try this site for photos: http://spotks.blogspot.com/

EDIT --------


Picture shows the gap between the unstressed front motor mount and the frame of my bike as it is almost 0.2 inches. The solution is to shim this gap.

Picture shows my test where I used washers as shims to test my theory. Result - excessive vibration is GONE. The bike is very smooth and the handlebars don't jump around at idle.

Picture shows the final result. I cut some brass shim stock to fit and used longer bolts to accommodate the shims thickness.

Picture shows a scissors jack and block of wood I used to hold the engine up when I had the mounting bolts removed. I had my wife steady the bike and hold it level while I worked on the mount.

 

I tried it and did not feel a real difference , only the stock bolt was too short and I stripped the lower hole (I realize that don't sound right) so I had to use a longer one, so if you do that mod make sure you get the same size bolt , but at least 1/4 " longer. Or do this : https://www.hdforums.com/forum/dyna-...today-wow.html

 

Thats it, great thanks for that.
Scouser