Announcement

Collapse
No announcement yet.

bouncing speedo needle

Collapse
X
Collapse
 
  • Page of 1
  • Filter
  • Time
  • Show
Clear All
new posts
Previous template Next
    #1

    bouncing speedo needle

    When the needle on my speedo hits 50 mph, the needle starts bouncing frantically covering about a 20 mph range.

    Is this a speedo head problem or a cable problem? What is the best type of lube to use for the cable? What about the speedo head? Is it toast or it possible to lubricate it without ruining it? I am a little leary about pouring lube into it?

    Junkman
    Tags: None
    #2
    Re: bouncing speedo needle

    Usually, the problem is in the cable and not the speedo. Sharp bends or pinches in the cable routing can cause this, or dirt/rust in the cable housing, or lack of lubrication. I had this problem when I rebuilt my 750. I removed the speedo cable from the bike, pulled the drive wire out and flushed the inside of the housing out. Then cleaned off the cable and coated it with chain lube and held the cable housing vertical and shot chain lube into it until it ran out the bottom. Put the drive wire back in and reinstalled it. When you get the housing/drive cable routed, before hooking up the ends, spin the cable with your fingers. You will be able to feel any kind of binding. There can be no binding.

    Earl

    [quote="Junkman Frankenbiker"]When the needle on my speedo hits 50 mph, the needle starts bouncing frantically covering about a 20 mph range.
    Komorebi-The light filtering through the trees.

    I would rather sit on a pumpkin and have it all to myself than be crowded on a velvet cushion. H.D.T.

    Comment

      #3
      Thanks Earl,

      I'll give that a try although, I now have a recollection that I have tried using this speedo head on more than one bike in the past using different cable/housing sets. So, my suspicion is now leaning more toward the speedo head being the culprit. Any suggestions if that is the case?

      Junkman

      Comment

        #4
        Let's clarify.....speedo head is the instrument, speedo drive is on the wheel.

        If you have a problem with the drive, you may (or may not) be able to take it apart, clean, lube, and reassemble it. Some, unfortunately, have crimped edges that make them a sealed unit, and you have little option but to replace them, but others can be opened.

        If it is the speedo head that is a problem, you can try spraying a light oil/lubricant like WD40 into the base. Cable-drives basically run into a very light gear assembly that drives your odometer and spins a magnet under the dial, so that the dial/needle moves in relation to the magnetic deflection.

        Often, the heads are tough to take apart without causing damage. If lubrication does not work you can take the unit to a professional and see if they can repair it.

        I have no idea how much they would charge, but if the cost of pro work is too high, check E-Bay for another unit.
        Bertrand Russell: 'Men are born ignorant, not stupid. They are made stupid by education.'

        ​

        Comment

          #5
          My understanding is that the speedo head is induction driven with magnets, so I dont know what can be done there. (I've never had reason to disassemble one) I dont believe debris or sludge would have any effect on a magnetic field. The only thing I can think of is there may be enough dirt/sludge build up to restrict the rotation of parts.
          I am guessing it would be safe to clean the speedo head/drive with electronic contact cleaner such as sold by Radio Shack, but I have never tried it and it is only a GUESS.

          Earl




          [quote="Junkman Frankenbiker"]Thanks Earl,
          my suspicion is now leaning more toward the speedo head being the culprit. Any suggestions if that is the case?
          Komorebi-The light filtering through the trees.

          I would rather sit on a pumpkin and have it all to myself than be crowded on a velvet cushion. H.D.T.

          Comment

            #6
            my 2 cents

            I have heard of this problem on cars, it usually is a magnet related thing, the only wierd thing is usually the needle will bounce around at the lower speeds and then stop at higher speeds. I would think it is the speedometer. I had the same problem (but at lower speeds) with my GS, before I could fix it though the needle on the speedo broke, so I got a new(used) one instead!

            Comment

              #7
              My speedo and tach would both do this after a few hours of riding. All I needed to do was oil up the cables.

              Steve

              Comment

                #8
                its more than likely either the cable or the gear at the wheel. my cable was okay but when i took my front wheel off i discovered that the gear mechanism was coming apart inside. there was a small c clip that had popped out of it's groove.
                you might want to check that out.....................

                Comment

                  #9
                  bouncing speedo

                  Thanks guys! I will lube the cable well, check for burrs and unravelling. I will also check the wheel drive as I have not had it apart yet to check its condition. Has anyone tried putting lube into the speedo head itself at the cable connection? I realize that the speedo needle is magnet driven but, I am thinking there might be some drag from dirt or corrosion right where the cable goes into the head. I don't want lube to go too far up into the mechanism though or get onto the inside of the glass.

                  Comment

                  Previous template Next
                  Working...
                  X