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  • Rubber Fork Boots

    I'm assembling my front fork and I'm confused by the fit of the rubber gaiters (boots). I'm using OEM Harley boots 46001-54, which I purchased in sealed plastic Harley packaging. The lower legs and boot retainer assemblies are all OEM as well.

    The bike is in the air on a frame lift, obviously with the front legs fully extended. With the boots slid onto the lower legs, there is a 2-1/2" gap between the top of the relaxed boot and the landing area on the boot bracket. Therefore, I have to fully stretch the boot as far as it will open to make it onto the bracket. I just don't remember the boots being stretched so long when the bikes were in the air. The pertinent measurements area as follows:

    Fork tube: 22.75" overall length
    Fork Boot: 5.5" fully relaxed
    Gap between top of installed lower leg to bottom of boot bracket: 7.0"
    Gap between relaxed boot (installed on lower leg) and bracket landing area: 2.5" (amount of necessary boot-stretch).

    It's been a long time since I've worked with early Sportster fork boots so I'm relying on not-so-reliable memory here. But I just don't remember having to stretch them this much to install them on fully extended fork legs and I don't remember how much the legs will contract when the bike is on the ground, which I'm unable to do so of yet.

    Also - are there any tricks to keep the felt washers in-place on the underside of the boot brackets?

    Thanks...
    Bill Pedalino
    Huntington, New York
    AMCA 6755

  • #2
    OK - here's what I've discovered thus far:

    I think that the upper hydraulic dampener bodies in the lower legs were installed incorrectly when I took them apart and I cleaned, inspected and re-assembled them in the same way. If these were originally installed incorrectly, the assembled fork legs would be approx. 3/4" longer than stock.

    I believe that the incorrect assembly is due to an upside-down upper dampener valve body in the lower legs P/N 46160-68. It was originally installed with it's open end facing up and I think that the open end should face down. When facing down, the assembled lower legs would sit about 3/4" closer to the bottom of the triple tree which I believe is correct. Can anyone please confirm the correct installation of the upper valve dampener body?? Can someone also confirm that the lower valve dampener body (46231-68 - with the drilled holes) also sits with its open side facing down toward the bottom of the fork tube lock ring??

    I have also taken the following measurement and I would greatly appreciate it if somebody would confirm that it is longer than stock:

    With the fork legs fully extended, the distance from the top of crown plate (there the top fork tube nuts sit) to the center line of the axle = 31" (measured on left side, but should be the same on both sides). I may be wrong, but I think it should measure about 30-1/4".

    Thanks,
    Bill Pedalino
    Bill Pedalino
    Huntington, New York
    AMCA 6755

    Comment


    • #3
      Bill pictures are worth a thousand words, The gap will close when the bike is on the ground and the front wheel is on it if all was done right. Post some pics.



      1959 XLCH

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      • #4
        Bill,

        If you go back to the link I sent you some time back and check the gallery section, specifically the 67 and 69 XLCH's, you will see what he correct boot stretch length is for the "early" (52 to 67) front forks and 68 and later forks with the bike resting on its own weight.

        Dave

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        • #5
          Murph,
          Yes, a picture is worth 1,000 words. That's exactly what mine looks like. So I'm OK.

          Dave,
          Yes, I'll go back and look at the boot-stretch.

          Thank you both ...
          Bill Pedalino
          Huntington, New York
          AMCA 6755

          Comment


          • #6
            Murph/Dave,

            As per Murph's request, I've attached a couple of pics of the installed front end - If I've inserted the attachments correctly.

            I must say, doing this operation brought back many memories of working at Gil's Cycle in the late 1960's! Back then, EVERYONE who bought a Sportster came to Gil's to have us install extended fork tubes. 'Frank's Forks' did a brisk business back then. On the downside, its disheartening how 40 years can erase so many of the fine details of an operation that was once so repetitive! Thank you all (and my many other AMCA colleagues) for refreshing my memories and for the many 'AH-HAH' moments.

            Please excuse the condition of the front fender - It's on there to tweak the alignment and I haven't gotten a chance to strip it yet - you will notice the ongoing gas tank-stripping operation on my bench.

            DSCN2236.jpg
            DSCN2238.jpg
            DSCN2237.jpg
            Last edited by billpedalino; 02-15-2015, 08:30 AM.
            Bill Pedalino
            Huntington, New York
            AMCA 6755

            Comment


            • #7
              Well, it looks like the fork length problem is NOT solved and the extended gaiter is an indication of something else that is incorrect. I took the bike off of the frame-lift and placed it onto the table lift. While doing so I noticed that when the bike's weight was applied to the front end, it didn't compress at all. Red flag No. 1.... I then placed the bike on the side stand and it leaned way over - like when we used to extend our fork legs and forgot to extend the kick stand. Red Flag No. 2..... I then stepped back and looked at the bike in the upright position and noticed that the bottom frame tubes are obviously not approximately parallel to grade. I know that the stock geometry was not exactly parallel, but this is obvious.

              I then placed the bike onto the table lift with the front wheel chocked and the bike in the vertical attitude and raised it up to take some measurements. The forks definitely look to be extended, which is confusing as my notes state that the stock fork tubes that I installed are the correct 22-3/4" long.

              Given the above can anyone please give me the following dimensions:

              1) Bottom of triple tree casting surface to top lip of fork leg (slider)... - I have 8" with the weight on the front end.
              2) Bottom of triple tree to Center line of axle .... I have 22-5/8", loaded.
              3) Frame-to-ground (below lower front motor mount bolts)... - I have 8".

              At this juncture, the conclusion that I'm leaning toward is that the lower legs are from the earlier XL and the internal dampener units are from the 1968 and later models. However, I'm told that this should be a direct swap if the slider anchor bolt holes are drilled to 7/16" diameter to accommodate the larger anchor bolts, which I did. Also, the original springs were broken, so I used a set of Ted's springs. I'm hoping that they are not too stiff, thus not allowing the bike to 'settle down' a bit when the weight is applied.

              Before I take the assembly apart, I'm hopping for a a little more information from some of you guys. However, at this point my patience with this bike is waning and I think I'll may take another 'time-out' on this one, throw a tarp over this beast and work on my '53 FLE motor for awhile!
              Last edited by billpedalino; 10-18-2015, 10:37 AM.
              Bill Pedalino
              Huntington, New York
              AMCA 6755

              Comment

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