This is probably going to sound dumb and I'm sure its been covered but I couldn't find the answer.
Can a non rubber mounted shovelhead be rubbermounted? I've got a '79 FXS and wondered if you could take the motor out and move the mounting tabs and rubber mount it? Would something catastrophic happen?

 

????
You can put yer '79 engine into a rubbermount chassis.
If you can make your '79 Chassis into a Rubbermount...Post Pictures....Lots of Pictures

 

Well I mean, I'm sure it CAN be done. My thing was I just didn't know if there was any real difference in the motors aside from the way they were mounted? So theoretically it should work. Right?

 

the engines themselves were common, the frames and motor mounts were the variables.

 

There's not enough room in the '79 frame for you to rubber mount the engine/transmission unit.
There's no realistic way to make enough room in that style of frame for a rubber mount set up, if there was, Harley would have done it years ago.

The reason the Softail line of bikes don't have rubber mounts is because they don't have the room in that style of chassis to do a rubber mount set up and retain the look that they were trying to achieve, which is similar in many ways to the earlier superglide chassis like yours and to the older rigid frames..

The only way to do it would be to find an FXR frame and put the '79 motor in it...but that would be a waste of a good FXR frame.

Keep your '79 the way it is.

 

You cannot just rubber-mount the motor...the motor/trans/primary has to be rubber-mounted as a unit...so you would need a different trans/primary and remove the seat post from the frame...while nothing is impossible, if you had the skills to accomplish this you wouldn't be asking could it be done...need to just get a rubber-mount bike if that is what you want...good news is most rubber-mounted shovels are dirt cheap.

 

I realize that it would all need to be mounted as a unit, and the moving of the mounting tabs wouldn't be an issue, I just didn't know if it was doable because I wasn't sure if there was a difference in the years of the frame and if it would allow the motor to bounce around like harley motors like to do..
If harley would have thought about it I'm sure they would have been rubber mounted from day one, it was probably an afterthought.. Most changes that remain a permanent thing are I believe.

 

it was eric buell that came up with the rubber mount assembly - in the early 70s police started looking at other companys like kawie as they are smooth and a cop can ride them 8 hours a day with out to much fatigue - the solid mount bike sucks 8 hours a day, day after day riding it

so his design was used -- it is a completly different frame and mounting locations as well

 

Well held misconception ...Eric Buell had nothing to do with the design of the rubber mount or the FXR...when he was brought in it was already built, and they were testing it... it just didn't handle well...he was responsible for "considerable stability and refinements to the chassis design" He received his engineering degree in 1979...first rubber mount was 1980 model released in 79...when he started working at Harley there were already rubber-mounts on the showroom floor.

 

my 80 FLT is supposedly the first 80 inch, rubber mount, 5 speed