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Building a Shovelhead 5 speed

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  • Building a Shovelhead 5 speed

    Howdy Folks. I'm going to do a 5/4 build, and to make for easy reading with out a bunch comments, please hold your comments until I finish the thread.

    Thank you in advance,
    Last edited by 68shovelbobber; 03-10-2012, 06:17 AM. Reason: Addition

  • #2
    PAGE 1

    Howdy folks, I have been meaning to do this wright up for a while now, but my watch stopped working and I just lost track of time. HUH!!!

    I have built a couple of these transmissions over the years. The first one I built was for myself, about 6 years ago. I bought a new take out, Twin Cam gear set from a customer, and had it just sitting around. So I used it.
    The objective of my build was to have a transmission that functioned like an over drive, but was still able to pull out on a hill in low gear with a 74" engine. I have seen it at least a hundred times on here, said, "but it is still a 1-1 ratio in high gear". That is true, but, with a 3.24 ratio first gear, it is possible to use taller gearing. I used a 25 tooth sprocket on the transmission and a 47 tooth on the rear wheel. With those sprockets, my final drive was around 2.90, compared to a stock Shovel ratio of 3.55. Unless I'm going at least 48 MPH, I would be in 4th gear. It could wind out ot 80 MPH real easy, then shift to fifth. I don't ride my bike hard ashifting in to 5th at 80 wasn't revving the engine much at all. Objective complete.
    Chris (inverse121) did an excellent write up on one of these transmissions. See his post;

    On this particular build, the customer wanted an all natural finish, including the kicker cover.

    Well, lets get going on the build.

    I have used the S&S cases, but they are a little more pricey than the Rev-Tec. The RT cases come polished as in the pic below. The only thing that is the same on your 4 speed transmission case and this one is the 4 studs on the bottom. That's it, nothing else. If you want to build a five speed, you need a 5/4 case, period.

    This is the RT kicker kit for this transmission. It is a nice complete set up, including the main shaft and all the small parts necessary for installation. This will accept the stock clutch hub and clutch set up. All 4 speed parts are interchangeable with this kit. A kicker is not necessary, you can use an OEM door which will bolt right on to the RT case.

    Here, the kicker assembly was disassembled for glass beading. The kicker to case adapter is also polished.

    Here are the parts after going thru the glass bead cabinet.
    Last edited by 68shovelbobber; 03-09-2012, 05:39 PM.


    • #3
      Page 2

      After thoroughly cleaning and blowing dry the parts, the main bearing is installed into the case. If you heat the case up to around 200*, the bearing will just fall in. Just to play it safe, I use 4 drops of blue Locktite, or medium thread locker in the bearing bore. That is to make sure the bearing OD does not slip in the bore. I would never use any strong or permanent thread locker, as removing the bearing would be a pain in the butt and possibly damage the case. This case takes the 79-84 style ball bearing, the S&S case takes the slightly larger 85 and up ball bearing. Compare this bearing to a 4 speed main bearing. BIG difference!

      Next, the Andrews fifth gear will be pressed into the ball bearing. The retaining ring has been installed in the groove in the case, and the inner bearing race will have to be supported. The Andrews gear is next to the OEM 5th gear.

      The back side of the main drive gears.

      Here is an Andrews fifthe gear next to an early 5th counter shaft gear. Notice the spacer leaning on the gear and the width compared to the Andrews gear.


      • #4
        Page 3

        Here 5th gear is being pressed into the bearing. As stated before, the center bearing race must be supported, or you may bust the case.

        Here is what was used to support the bearing. Do I recycle? Yes!

        Here is the main bearing seal, sprocket spacer, and the 5th gear quad seal. The quad seal is the reason these transmissions don't leak. The Sputhe transmissions don't use the quad seal, and they are prone to leaks. The metal faced seal is a Cometic, but I have used James also, which are rubber coated. The Cometic are a tight press fit, the James can be pressed in with your fingers if you are a weight lifter.

        I should have mentioned this earlier, but forgot. If you are using an Evolution shifter assembly, no modifications to the case are necessary, but the TC assembly requires the case to be clearenced, see the red marks. A dremal tool can be used if you don't have a milling machine. I usually mill about .040 deep X 1/4 in wide (1/4 inch end mill) That is so the pivot detent and spring don't dig into the case. Do this before installing the bearing.


        • #5
          Page 4

          I prefer using the TC shifter assembly, but it does require a little more work. Shown below is an Evolution and Twin Cam shifter, the longer one being the TC.

          When installed in the case, here is what you will have. Notice how much sticks out, about 1/4 inch.

          After taking a measurement between the washer and retaining ring (in the picture above), I machine a space to fit onto the lever shaft. I like to allow about .015 free play. Keep in mind, "free play" doesn't cost any thing.

          After fifth gear is installed, and the counter shaft bearing, this will be the first part to put into the transmission. If you install the gear set first, this part will not go in. Here a sleeve is slipped over the spline and the seal tapped in. I made a tool to install the seal about .015 below the case surface.


          • #6
            Page 5

            Here is a picture of the case after the machining is done for the shifter drum. The tool is what you will need to expand the gear retaining rings. If you over stretch them , they could fall off. OUCH!!!

            This is one of the things I don't like about the RT case. The holes that the screws are going thru are not blind holes, but open the transmission oil. What I do is install a couple of 5/16 X 1/4 inch long set screws in the holes, and locktite them. If you don't do that, the threads will wick oil out and could potentially leak. YUK!

            Here is another view of the thru holes.

            Here are the set screws I use.


            • #7
              Page 6

              Here the main seal and sprocket spacer will be installed. Be sure to slip the quad seal onto 5th gear before installing the spacer.

              Because the Cometic seal is such a tight fit, it must be pressed in.

              The counter shaft bearing is being pressed in here.

              The kicker gears are re-installed on the main shaft, and installed in the kicker adapter. You can see the thee bolts in the housing. They are used to support the housing while the gears are installed on the shafts. It is much easier to do it that way vs. laying the thing on the bench.


              • #8
                Page 7

                Ready to install the gears after the counter shaft is pulled in. It must be "pulled" into the bearing, as pressing the shaft into the bearing with out some type of support may damage the bearing. I have the Jims door remover/installer tool that I use. Keep in mind, the counter shaft has to be shortened. That information is available on S&S's web site.

                I am not going to waste time/space here, that is why you should have one of these. It will give you all the specifics, what I am doing here is giving you information that is not available in the book.

                I made this tool to hold the shafts when tightening the nuts on the counter shaft and the kicker gear nut. You could jam it between gears to lock it up, but I don't like to over stress the shifter dogs. It is a 5th gear that has a 1/2'' shaft welded to it.

                The counter shaft is being pulled into the right side counter shaft bearing.


                • #9
                  Page 8

                  Here the kicker gear nut has been installed and torqued to specs. At this time, the adapter will be removed and the gears installed on the shafts.

                  After the gear build up, be sure the shifter pawl is installed in the case, then install the gear set in the case. Again, there isn't much sense in going thru the final assembly, as that is covered in the service manual, and it is a strait forward install with out any surprises.

                  I feel that the information I provided you with here, you can determine for your self what your capabilities are, and if you would care to try building one of these for your self. I have 2 more of these transmissions to finish for customers, then I'm done. I am 60 years old, am in the process of liquidating my old school "mom & pop" motorcycle shop. That is why I haven't been spending much time here on the forum.

                  I have a couple of 5/4 cases left, and about 4 kicker kits. If any one is interested in them, let me know.

                  Thank you folks for being a great bunch of guys. Take care and ride safe.

                  Last edited by 68shovelbobber; 03-09-2012, 05:47 PM.


                  • #10
                    Well worth the wait tony thanks ( i hope you were done)


                    • #11
                      Thanks Tony.
                      Very informative and very generous of you to show us.

                      One day would you mind showing us how to do this without a kicker and which main and countershaft are needed?
                      Agony sometimes changes form but it never ceases


                      • #12
                        Hi Chris,

                        for a non kicker transmission, you can use an Andrews 1979-early 1984 main shaft, but you will need a special bearing and seal. S&S includes them with their case kit. I prefer the Rev-Tec main shaft, as you will still use the standard inner primary bearing. I like standardized parts, vs. special parts.

                        Any of the 5 speed transmission doors will work, from the early 5 speed FLT's, up to and including the 5 speed Twin Cam doors. You will need to use a Softail style cable on 87 and up doors, the ones that screws into the end cover.


                        • #13
                          thanks for sharing....

                          it takes alot of time taking pics and writing stuff.... and building stuff!

                          much appreciated,,

                          thanks // Kenneth
                          "Good judgment comes from experience. Unfortunately, the experience usually comes from bad judgment."


                          • #14
                            i'm proud to say (and tell anyone that'll listen) that i have one of your transmissions in my sled Tony........thanks.


                            • #15
                              Sorry to hear that you're giving it up, but good to know that you can get some well deserved free time. Also good to know that every time that sly grin goes across my face as I'm clicking into high gear and pegging the speedo at the same time, it's cuz my shift linkage is hooked to one of the last of the best.

                              Thanks for the how to, and wishing nothing but the best for you and yours.
                              Behind every smile, is a set of teeth.