My new S&S 107" had all manner of strange vibes when new and took a good many miles to smooth out. What brand is your 131"?

 

To close out this saga on my end, I replaced the Biker's Choice mount with the original after inspecting it. The excessive vibration went away immediately and the bike is a joy to ride again. I'll follow the recommendation of Texashillcountry and Gbrown above when it's time to replace the mount and go OEM. I rode with the Biker's Choice mount for at least 200 miles and it would still shake the heck out of the bike at 1200RPM and was pretty rough through 200-2500RPM. Didn't seem like it eased up a bit. Put in more time than I wanted on this but learned a quite a bit in the process.

Thanks to all for your help.

Frank

 

I learned in the early 90's that if it comes from JP it's usually junk. I won't buy from them or a lot of online retailer for that matter.

 

grbrown - I have the Ultima 131 with roughly 150-200 miles on it now. It is f*ckin flat out violent around the 2000-2800 range then smooths out after 3k. Rough enough that it started stressing the FXRT lower fairings mounted to the upper. Im picking up an OEM mount today for another $80 dam dollars and will swap out this Alloy Art tonight to see. I introduced so many variables that its hard to determine whats causing what since its a frame up build so Im hoping its just the mount at this point and not just a beast of a motor.

 

Good luck on the new mount hopefully it works

 

Just to report back my findings. I stopped by the local HD and picked up a new motor mount which is item number 16207-79. Ok so pay attention here, this has been redesigned and the old style in most parts books for FXR ends with a "B" the one being sold now ends with a "D". IF you buy a new one pay attention to the number you get as they mount differently. I have added a picture to show you each and what the redesigned one looks like upright so make sure you don't put it in upside down.

Back to the point, took my Alloy Art mount out and put the new "D" version OEM rubber mount in.............. holy Sh*t! Night and day difference. No more violent rattles or vibrations from 2-3K. Smooth as butter. There is slight roughness around 1500-1800 but that could be various things, new motor still breaking in, not tuned yet so could be sputtering, could just be bogging the big motor down too much, etc. But really who cares. 95% of the time in motion you should be above 2K rpm anyways. So if you put a new poly type mount in and cant take the rattles go back to OEM, or if you have a new OEM and it shakes make sure its in there properly as I read last night even some dealerships were putting the "D" mounts in upside down as habit.

 

No Idea why my attached picture isn't showing as it showed uploaded but here is a URL, maybe that will work

https://i.imgur.com/yCU8MR3.png

 

I have found none of the EVO mounts are good much longer than 5 years.
At that time they are ready for the trash.
The swing arm is sagging and it all need to be refreshed.
In fact, the swing arm inside bushing get egg shaped from just sitting there,
Oh I know-Some here will say they last a lot longer...and yes you can put up with the misery lot longer if you like.
AT the same time they are complaining about a bike that drives like it has a drunken mind of its own.

 

Thanks for the D model mount info, I hadn't heard about that and will changing out a '96 soon, good to know. I was thinking about one of the American made poly mounts, but sounds like this time OEM is better.

 

how about this one ?
https://dirtycustomz.com/products/fr...-flhx-fltr-flt