Six speed upgrade

[Johnnyshvlhd]

Has anyone put an Ultima six speed in a four speed frame, mated to a Shovel head?

[a_disalvo]

My local wrench told me to stay away from Ultima transmissions. I just installed a revtech 5/4, works great. ( If you can find one at list price). Frank

[Buglet]

     It can be done but it is a lot of work, you have to use a soft tail primary and starter set up. I done one years ago it ended up working great. Is it worth it the is hard to say.

[Johnnyshvlhd]

Thanks Buglet, did you have to modify the frame. I'm aware of the primary upgrades.

[Johnnyshvlhd]

we made it happen

[capn]

you dont have to modify the frame.

[JW113]

Do tell! I'd like to here what you had to do to squeeze it in there.

thanks,
JW

[billbuilds]

        We'd really appreciate it if you could give us a rundown on how you guys did this. Photos really help too.  Bill

[capn]

The flange on the left side of the trans case has to be notched to fit around the forward end of the swingarm.You will loose the two bottom mounting holes for the inner primary. you also need a different mounting plate.A couple places sell the plates.

[JW113]

You mean two holes that mount the inner pri to the trans? Leaving only the other two? Hmm. I've not done the math, and that might be OK for stock (although HD did not think so), but for any added HP from bigger motor & such, that does not seem like a good idea. To me, anyway...

-JW

[capn]

You end up with the two holes at the front of the trans and also the two at top the where the starter bolts.

[Buglet]

  I did one years ago, did not loose any mounting holes in the primary. Had to machine a little casting next to the two rear mounting holes and notch the transmission for the swingarm mount. Redo the oil tank to battery box mount and made a new battery box to fit the standard HD battery to clear the starter lug.   

[Johnnyshvlhd]

Here is what we did, first thing was the tranny plate. Bought off eBay was listed as a Softail plate. I seem to remember tweeking some of the bolt holes to get it lined up. The swing arm mount is in the way. We didn't like the idea of loosing a mount point for the inner primary (96" engine) so (after much deliberation and debate) hacked off the swing arm mounts and re welded them facing reward. Ended up using A BDL 3" belt drive and everything bolted up fine. The stock square oil tank and battery box had clearance issues, got an Ultima round tank (still a tight fit with the starter bolt terminal). Haven't gotten any road time yet (pretty crappy weather here in Ohio) But she's running and everything goes around like it should. For now we are using the original top shock mounts with 14" shocks. It's a Jammer frame.

[bump]

Seems like a lot of work to get the same final gear ratio.

[capn]

Six speed has taller final ratio than 5 or 4 speed

[crock]

Seems a moot point, but what are you gonna do for rear fender mounts?

[Johnnyshvlhd]

We didn't lose or alter the fender mounts. The fender is attached to the swing arm.

[Ohio HD]

Six speed has taller final ratio than 5 or 4 speed

The OEM HD six speed is the same final ratio as four or five speed OEM HD transmissions. 1:1.

The Ultima, I don't know what their final ratio is.

[nibroc]

 

             good call Ohio

                                             

[JW113]

Nice work Johnny! And clever solution for making clearance around the swing arm. I've often though of a 5 or even 6 speed for mine, but then always fall back to "will it really make it any more fun to ride?". Not really, but then, mine is purdy much bone stock.

-JW

[Johnnyshvlhd]

Thanks JW, not sure if the handling will be much different or how much shock action will be affected. My first home build is on a Sundance four speed style frame. It is stretched out, if I recall correctly, two and a half inches. Feels a little different but nothing radical. The real reason for the six speed is that we got a really good deal at a local swap meet, couldn't stand it just sitting around collecting dust.

[kd]

That 2 1/2" should hold those wheelies to a minimum.  That may be a workaround for a  restricted rear fork length at the drag strip. 

[bump]

I have a 78 shovelhead and a 02 FLHTCI in high gear at 3000 rpm they both are running 70 mph.

[JW113]

That added wheel base will put it about the the same as a Softail. So should handle just fine.


And good point, waste not want not!

-JW

[76shuvlinoff]

Nice work Johnny! And clever solution for making clearance around the swing arm. I've often though of a 5 or even 6 speed for mine, but then always fall back to "will it really make it any more fun to ride?". Not really, but then, mine is purdy much bone stock.

-JW

I have a 5 inna 4. I liked the betweener gearing riding two up or loaded for a trip but lament exhaust limitations since the kicker cover sticks farther out to the right. I have often wondered if I eliminated the kicker if I'd gain any space for pipes. As for off the shelf pipes I only found Paugho true duals or a Thunderheader to clear it.  Would I do it again today? Probably not. I have had a TC touring bike for 8 seasons for two up or taking a trip. As for the 76 with a 93" mill there isn't really any need for 5 speeds plus I intend to strip her back to bar blaster mode this next season.

In my case the factory 4 speed needs a complete overhaul before it ever went back in.