No announcement yet.

Fancy motorcycle plate holder

  • Filter
  • Time
  • Show
Clear All
new posts

  • Fancy motorcycle plate holder


    A friend from work moved over from Europe to the US in January and got himself a Japanese "Harley wannabe" motorcycle. He really loves it and he likes to "spice it up" with various gadgets.

    I don't actually recall how he heard that I have a somewhat complete machine shop in my garage but a few weeks ago, he told me about this fancy plate holder that he had for it. The holder was supposed to be mounted on the hollow rear axle, but the hardware it came with to mount it to the axle was not doing the job.

    So, if you are into motorcycle perhaps, or into finding the most time consuming way to mount a license plate on a hollow axle , you may want to take a look at the posts that will follow in the coming hours and days.

    They should contain a fair amount of pictures and only minimal but informative narration.
    Last edited by jariou; 10-09-2017, 05:06 PM.

  • #2
    I have built a fair amount of plate holding hardware. The axle is not always the best places but it wil, eliminate welding..usually.
    First thing I would consider.. will your efforts be legal ?
    Much of what I did was what .ca you make me to get me legal again.

    I one made a plateholder that was 2 pc, 3/8 total thickness, no threads showing, that was a bit tricky.


    • #3
      Here is the machine

      Ok, so here is the machine with the owner.

      And here is the rear axle to which the plate holder must hold on.

      And here is the plate holder installed. He still has to handle the wiring properly. I don't get involved with that.

      So that's it for now, I will show the parts to be built in the next post.


      • #4
        Here is the problem...

        Here is the arm on which the plate holder is screwed.

        Below the arm, you can see a bushing and a washer as well as two cylindrical parts, one of which carries an O-ring.

        Here is a picture of those two parts on their own.

        Apparently, the intention was for those two parts to be screwed together while they are inserted into the hollow axle, and the O-ring will expand and hold everything tight to the axle.

        Well, that system had already failed. So, my mission, if I was willing to accept it, was to create something similar but more effective to connect to the axle.
        Last edited by jariou; 10-17-2017, 04:23 PM.


        • #5
          Originally posted by jariou
          I made another post to continue this thread 20-30 minutes ago. I saw a message that popped up about a moderator reviewing the post, and it seems to have disappeared!

          Could some moderator enlighten me? Did the post really disappear? I can't find it in my profile.
          I can't figure it out either. Your post did go to moderation, though it shouldn't have considering your post count. Somehow IT mucked things up when they changed software and then changed back; some settings in the control panel no longer function.

          I did see your post in the moderation bin and did click on "Accept," but have no idea where it went. It should have popped up immediately. Sorry about the hassle.
          Traverse City, MI


          • #6
            I would just keep it on the backrest like it is in the first picture. It seems to be sticking out pretty far sideways on the axle. YMMV.
            Kansas City area


            • #7
              The beginning of a solution

              You may have noticed that the axle ends in a hex shape. I happened to have 4 or 5 inches of 3/4" hex steel. It fit perfectly in that part of the axle which is about 1/2" long. This way, I wouldn't have to worry about the part spinning around and it would be locked in.

              After the 1/2" or so of hex shape, the axle hollow is round and around 0.720" so I essentially built an expanding arbor from a piece of hex. I turned both ends and kept a hex registration in the middle and then I drilled the whole part through with a 1/2" - 20 tap drill. I then tapped the part with a taper tap and I stopped tapping when the end of the tap had just started to poke out of the other end.

              I then drilled 6 stress relief holes around and cut as many slots with a slitting saw.

              Here is the end result with the set screw used to expand the arbor.

              This gives a lot more positive lock inside the axle than the expanding O-ring could ever provide.

              Then, I took a bolt and turned the head off to screw in the other end of the arbor.

              Last edited by jariou; 10-12-2017, 08:26 PM.


              • #8

                I don't have a bike and I don't argue with the "customer".

                He had the thing to put it on the side but it was not working properly.

                I am not suggesting this is the way to go. I'm just telling my story. It's a little dull for now but you should find it a little more interesting in a few posts if I can get them to show up after I do put them up!


                • #9
                  Just making an observation. I think it's great that you are trying to help the guy. I'm looking forward to seeing what you come up with. I am always glad when someone with our skill set can solve a problem. Best Regards.
                  Kansas City area


                  • #10
                    So now, all I need is a nut to put on the stud and we're all done!

                    But no! It would be way too simple!

                    I asked my friend if he would like a "fancy nut" to go with the rest of the bike style! His eyes lit up as he said "Yes, that would be great!"

                    Here are a couple of images of some bike accessories that inspired me for the nut design.

                    Can you see a "theme" here?

                    So I turned an arbor with a 1/2" - 20 stud thread on the end, I drilled and tapped a piece of 1-1/4" round 316 stainless and went at it.

                    Here is the result.

                    Notice that there is still a small matter to worry about... That is, how will one be able to unscrew the nut from the arbor without mangling the part with marks left by vise-grip jaws or other uncivilized tool or method!

                    That problem did enter my mind as I was turning the part, but it was not enough of a worry to stop my progress. One problem at a time, I thought to myself, one problem at a time!...
                    Last edited by jariou; 10-17-2017, 04:26 PM.


                    • #11
                      I was going to suggest an expanding hex arbor too If I were to do it though, I'd cut a taper in the hole going through the expanding bit and make a threaded rod with a matching cone at the end. Then you could pin it to what ever fancy outside widget you want (like in your last pic), mill a couple of spanner flats on the edges or behind the widget to tighten up the arbor.

                      to be honest I think that the adapter will be the easy part. Hiding the cables so they don't look ugly will be the difficult bit!


                      • #12
                        I never understood why some people want their license plate mounted like that. I've seen it done before and always wondered what the appeal is.. I could understand wanting to lower it, but why not mount it right under the rear fender then.


                        • #13
                          I hate to see those spiked style nuts, I have dropped a few bikes in my time and it hurts, no sense in adding medieval torture.


                          • #14
                            Well, I was wondering if anyone was following this thread. I guess I got my answer.

                            So, for those who followed so far, the problem at hand is now to remove the "spiky" nut from the mandrel/arbor I had it screwed on for turning. Flats would definitely work, but then it would be too simple! Plus it might damage the aesthetics!

                            So I machined 6 holes 1/4" in diameter in the face of the nut.

                            And here is the end result on the same arbor.

                            Now, we have features onto which to grab, but nothing to grab with! Not to worry, I turned 6 pins about 0.235" and pressed them into holes on a ring that will act as a "custom wrench".

                            I could finally use the custom wrench to liberate the nut from the arbor.

                            Last edited by jariou; 10-12-2017, 08:30 PM.


                            • #15
                              You may have noticed a hole on the side of the wrench above, it is so as to be able to put a tommy bar in there to be able to torque the nut properly. Of course, anything could be used but why not complete the job by providing the customer with a complete solution.

                              There is also the 1/2" - 20 set screw that might need a tool so why not kill two birds with one stone.