I had some really bad vibrations at a certain RPM on my 06 street bob. I took it to two different stealers and they both looked at me and said "Hey, its a Harely, that is what they do". Well BS,I have a couple of buddies with them and they do not vibrate this bad, and I know that others have talked about this also. So, I was going to solve it and possibly have.
What I did was tried to ordered a new lower front Isolator (Rubber motor mount) and well they are back ordered, along with the rear, so I got to thinking that something is strange here. Alot seem to be ordered and they verifed that alot are being ordered. So I wondered if there is something here. So I got one, and as I installed it I noticed that there was about a 1/4" space between the alum. mount that is on the motor and the two verticle tabs that bolt to it. So to tighten the thing up, you are compressing the rubber mount, which takes away the "rubber" isolator is some capacity. So we made a spacer, installed, check the vehicle alignment and then tightened it down. Started the bike and guess what, vibrations are basically gone. The other guys that were helping could not believe it. One has been a bike wrench for years and he was impressed at how much better the bike was and how poorly the motor mount was built that we would need to make a spacer to work correctly. With out the spacer the mount is loaded alot and has very little give not allowing it to work as it was orginally designed.
So I talked to the local stealer in the shop and he said that they had wondered about that before, and well now they are going to be looking at this alot closer because it seems I am not the only one asking about it.
Just wanted to pass this on to everyone. If you want further info let me know.

 

Thanks for the heads up I will have to try that I wonder about the back as well I will have to have a look at that also.

 

I just had my front motor mount replaced under warranty on my 06 Street Bob. It felt like a solid mounted engine, not rubber isolated likethe dyna's are, with loose mounting bolts between the engine and frame. It was especially noticeableunder deceleration from 45 mph to around 5 mph. With the new motor mount that feeling is gone. There is still plenty of vibration but now it is more like what you would expect from a Harley. It no longer has the hard to describe "harsh" vibration that it had before the new motor mount. I had personally done the engine alignment and motor mount adjustments and to no avail. I even took the front mount off to check the stiffness of the rubber and then went to the dealer tocompare that feel to a new one. There was not much of a difference but still the new mount made all the difference in the world to me. It was not something that you could see or maybe even feel but there was a problem with the mount none the less. Push for a new mount or pay for it your self you will likely be happy with the result. Good Luck PS: I was considering getting rid of the bike. It was that annoying. Don't let them tell you that it is normal.

 

I think this is basically what you are talking about - maybe just a bit different. Makes sense, if you load/stress the mount in it's static position, how is it supposed to do tyhe job it was intended for?

http://www.*****************/forums/sh...ibration+fixed

I know it's a different forum, but very well documented.

 

well - they edited my post - but you can figure it out.

 

Stranger, do you have any dimensions on thespacer you used? A drawing with specs would be great for those of us that could make our own. Thanks for the info.

 

ya maybe a pic for us to see. i kinda have a hard vibe on the decel right before it gets to idle rpms. i think this might help just would like to see a pic of the spacer installed and is it on the frame side motor side on top the mount or under it?? these i wnat to know.....thanks

 

I've heard of the inner part of damper, the aluminum piece with the two tapped holes not quite reaching the the mounting point on the frame. It's been well documented how making a spacer to bridge the gap makes a world of difference with regard to vibration reduction. In this scenario the mount would be stretched apart as you snugged down the two bolts to pullthe mounttight to the frame, understandable! But, squeezing the rubber slightly as the outer mount is bolted to the motor is a new one as it would relate to making the bike vibrate more. Keep in mind the mounts have no locater links in their vicinity and it's the mounts themselves that locate the motor horizontally! I know the distance you are talking about, as I have watched the same thing happen on my 06 Dyna, butIt's as smooth as can be in spite of how the rubber is compressed. In other words, your findings have mesomewhat confused.

Also, wouldn't you need two spacers, one on each side to maintain alignment?

 

I wish HD would adress this problem as well.Maybe someone will come out with an aftermarket one that will work right.

 

Cynic, To address your concern which is valid, I aligned the bike as perscribed within the book and after doing this, I only needed a spacer on one side, but good point, just lucky I only needed one. As far as what you have experienced with your own bike, I will just say you are lucky, because I know that there are several of us who are not so lucky, I just wanted to pass on what I think has worked for me.
Another interesting thing I learned, is that as you drain your oil and then remove your oil filter some oil seems to find its way to the rubber mount and this can deteriate the mount after time. They say if you use Synthetic oil there is not an issue.
As far as what the dimensions are of the spacer, we used the old one for the hole dimensions and then installed it, made of 3/16" steel plate. It goes next to one side of the rubber isolater and the alum. mount (that is bolted to the motor).
For fun, I took the old mount and put it into a vice and compressed the two ears of the mount towards each other 1/4" and then pushed on the mount and dam it was solid, alot different than if it was not compressed. The rubber mount should take up most of the harmonics and vibrations of the motor and to do so it should not be under that much compression, or it will almost act as a solid motor mount.
As some of you have asked, it was the worst under decel as you are describing. It could just be the new mount, I am not sure but what ever it is, there is something wrong with the existing mounts (Isolators) on some bikes, maybe not all as some have mentioned but enough that Harley should take some kind of action.
Try to order one and see when you can get one. I asked two shops, they are back ordered and not sure for how long. Tells me something is up if you ask me.
Glide05, what site is it?
I will do what I can to take a pic and show it.
I too was on the verge of going crazy and possibly getting rid of the bike, but I have yet to back down to a problem, including this one. Hang in there, there is a fix, just have to find it. I wish anyone with this problem the best of luck to solve it. Get a front lower isolator and try that. Best of luck.