Vibration problem fixed!

TylerIII · 04-14-2012, 05:30 AM

Havent put up a post in some time as the weather has been real nice and I eat, breath and sleep golf. Well fishing and riding the bob too. If you remember some time ago after I tore down the front end for powder coat and zombies I got this terrible vibration. I asked about the fall away test and heavy fork oil and was worried that I didnt put the bike back together right. I took everything down and back together and couldnt figure it out.. After research on the web I started looking at the front motor mount and some other vibration issues owners were having and stumbled on this..
Shimmed front motor mount today WOW - Harley Davidson Forums

I did this shim trick and vibration gone! I knew it couldnt have been the front end as the vibration was different thru rpm ranges and almost gone when I was at 65 in 6th gear.. This is when I started looking at the motor mounts... Here are some pics... Call me crazy but it worked...

see the gap when I removed the bolts?

Picture with shims..
A few more pics of the bob...I just need wheels, tires and new pegs and done for now..

HrdNox · 04-14-2012, 07:18 AM

Cool,I’ll keep this in mind.

Kidneybuster · 04-14-2012, 06:32 PM

Depending on bad tires, loose steering leading to unsafe riding, all dynas vibrate until the get up to a certain mph. They have rubber mounts unlike soft tails.

Dirk · 04-15-2012, 12:22 PM

I might try that.. I put a midglide front end on my LR this winter with heavier fork oil and Ive got this terrible vib @ about 2-2400 rpm range. But, I also fixed a broken bracket that was holding my pipe in the cam cover area, I thought that bracket being fixed is what surely put that vib in there, I will check my rubber mounts.

missedem · 04-15-2012, 04:44 PM

I had read about some of the motor mounts on these dynas (specifically the front motor mount) being bad, needing shimming , or trimmed down a bit. Good to know if the vibes go up that there is a simple fix.

I'm-Ric-Greene! · 04-16-2012, 06:05 PM

Nice bike man...looking good. I always forget about that trick...my mind always tells me..."the f'king front tire is out of balance"....thats what it feels like sometimes....but then you'll feel it in your feet....dynas got tha good vibrations.....

mixtacy620 · 04-16-2012, 06:57 PM

Gonna do this..inexpensive and cant hurt

Gommee · 07-25-2012, 11:59 AM

The shimming helps a great deal, but Harley put out a service bulletin (M-1324) in May about the front isolator. The front mount is sagging causing the top curvature of the rubber mount to rub on the metal frame transferring vibrations. They are recommending trimming a little off the top of the rubber to gain a clearance of 0.020 - 0.040 in.

TylerIII · 07-26-2012, 12:37 PM

I would love to see a picture of this to see how it is done. Great find by the way..

Gommee · 07-26-2012, 12:43 PM

The shim or the bulletin?

TylerIII · 07-26-2012, 12:51 PM

I already posted pics of the shim at the start of the thread./ It helped with my vibration however if I can trim a little here and a little there maybe it will ride even smoother...

I was wondering if there are pics of a trimmed shim and how it was done...

Hell, I d like to see the bulletin as well..

Thanks

Gommee · 07-26-2012, 12:54 PM

I sent you a PM with my email address. I will send it to you.

I was being a smart a$$.

I can take pics of my mount trimmed and shimmed when I get home tonight.
Just have to figure out posting pics here.

TylerIII · 07-26-2012, 01:07 PM

Didnt even notice!

Thanks for emailing the bulletin..

Gommee · 07-26-2012, 06:02 PM

As promised, I have attached pictures of my shim, shaved mount, and bulletin.

Shim: I used 1/4" brass flat stock. I believe the holes are 1.25" center to center.

Shaved mount: I went a little crazy with the shaving. I took most of the rounded area off with a razor knife and filed flat. You can cut it with the mount in, but it was much easier to remove the mount.

I have also included a copy of the HD bulletin pdf format.

TylerIII · 08-01-2012, 06:04 PM

After you shaved/Trimmed how did it effect the vibration?

Gommee · 08-01-2012, 11:10 PM

Quote:

Originally Posted by TylerIII

After you shaved/Trimmed how did it effect the vibration?

Vibrations are practically gone. Took it from 0 to 160 mph on the freeway. Such an enjoyable ride. It has not felt like that since it was new.
There are some "harley" vibrations, but nothing like the dreaded dyna vibes.

Before you shave, look at the curved rubber at the top of the mount. It is most likely rubbing on the top metal frame. This is transferring vibrations from motor to frame.

Look at the pictures I posted in this thread. I went a "little" overboard, but some others have as well. You may just want to make the clearance like the bulletin, but I did not want to pull it out more than once. Lazy I guess.

TylerIII · 08-02-2012, 04:31 AM

Great news and thanks for the update. Ill try this weekend.

0 to 160? Your crazy!!! HA

Gommee · 08-02-2012, 08:37 AM

Quote:

Originally Posted by TylerIII

Great news and thanks for the update. Ill try this weekend.

0 to 160? Your crazy!!! HA

Just a little!

I should not do conversions in my head! I will fix it when I get to a computer.

I was cresting just over 200 kmph which puts that between 125-130 mph.

It does not fix the fact that 6th gear is useless.

missedem · 08-02-2012, 03:08 PM

Quote:

Originally Posted by Gommee

Just a little!

I should not do conversions in my head! I will fix it when I get to a computer.

I was cresting just over 200 kmph which puts that between 125-130 mph.

It does not fix the fact that 6th gear is useless.

thanks for the information on the fix. I read the hd bulletin as well. dont know if youve ever ridden an evo model hd with a 5 speed above 80 mph or not but if you had you might change your mind about the 6th speed transmission. those old 5 speeds could vibrate your fillings out of your head at 80MPH +.