I want to build an Evo with a 4 speed style frame. I have a titled ‘76 but would rather not do all the cutting needed to fit the motor in it. Motor is stock sized 80” evo with S&S heads.

Ideally I’d find something like an ‘85 lowrider frame but wasn’t ‘84 sized for Evo as well? I thought it was available as an option.

just wondering if any earlier back than that the frames were sized to fit the larger evo motors.

i’ll be running sportster rockers to get a little extra room, and a 5 in a 4 trans.

 

1984 Softails had 4 speed frames and Evo engines. I don't know if any other models had 4 speed frames with Evo engines in 1984.

 

It is the 4-speed frame that is gonna throw ya.. All 5-speed frames will accept an Evo Engine!
As Said.. the '84 Softail??? Maybe I never seen one, with a 4-speed!!!
certainly the 1985 and 1986 FXB and the FXWG... tho they command a Premium...(except If I own it of Course)
S&S built an Evo Mill, specifically to go into the Typical (pre 1985) 4-speed frame...
At this Juncture, I would Not modify any Shovelhead, nor Shovel Frame to accept an Evo... you will Loose Money....Period.
But... Yer bike... Cut 'er Up and the rest of us with Survivors, Benefit!!!!

 

Yeah I saw the softail years, but I’m an FX guy. Just dreaming of a badass custom evo swingarm bike with a classic cast frame look, especially since I have the motor ready to go.

Love my dyna but want to go in a different direction looks wise. Might just end up getting an aftermarket SA frame. Unless someone wants to offload an early FX Evo frame! Not likely.

 

My buddy rides a 84 Softail, 80" Evo with a 5 speed and tapered shaft for the clutch.

Harley-Davidson introduced the 1,340 cc Evolution engine in 1984, and when the Evolution was used in five of the company's big bikes, the five-speed transmission was used along with it. The base model FLH was the only FL bike to retain the four-speed transmission in 1984; and even that changed the next year, when the FLH was modified to use the rubber-mounted Evolution and the five-speed gearbox. The Evolution engine debuted in the Sportster line in 1986, but the five-speed transmission wouldn't be used on a Sportster until 1991, when the four-speed gearbox was replaced by the five-speed on all models.

Copied this but also believe Harley used the remaining Shovel & 4 speed surplus in the 84 Softail until gone.

 

There were a very few FX Superglides in '85 with the Evo solid mount 4 speed,I've only seen one in the flesh owned by someone working at an H-D dealer.
Good luck finding that needle in a haystack.
Those transition years '84 & '85 saw some rare bikes like the '85 FLHP Shovels and the aforementioned '85 Evo Superglide.
I had one of the first Evo bikes an early '84 FXRS,chain drive and dry clutch like a Shovel.

 

My 85 FXWG is an Evo, 4 speed, Kick and Electric start.

 

Yup... 1985 and 1986 FXWG and FXSB (I believe was the Letters), were E-Motor 4-speed chassis...modified by MoCo...to accept Evo Mill..
is most Likely where the MoCo used up any surplus 4-speed trannys..
One aside... the Late 1984 4-speed (like the 5-speed) , got the Tapered shaft... but Not the "good" one... like the Shovelhead Clutch
I despise the Late 84 clutch, and would Gladly trade it out for the Good Ole Shovelhead Clutch... I think Only the Mainshaft changed, except there were 2... Chain drive and Belt drive... Complications abound

Back on track...Earliest Evo Motor Frames from the MoCo were 1979 for 5-speeds, and 1985 for the 4-speed... Softails???? IDK I guess I thought they were All Evo's
so 1984???

 

How hard is it to modify a 4-speed shovelhead frame to fit the Evo with 'sportster rocker covers'? A little dimpling or maybe cutting and welding on the back tubes?

 

The backbone of the frame needs to be raised to accommodate the taller Evo engine, even with the Sportster rocker boxes.