on the left, you see the speedo board being separated from the main
board. There are two sets of pins (top and bottom red arrows) that
unplug carefully, and one screw (centre red arrow) needs to be removed.
These pins have been reported to be the cause of malfunction of the
speedo, as they can become corroded from moisture entering the unit.
The Kfaqs describe how to clean them.
pins should be cleaned up in order to ensure good electrical contacts. I
sanded the pins lightly with very fine sandpaper and worked them in
their sockets a few times.
the board is separated, you can examine it for any problems. The light
bulbs are the small bayonet type, and have a flexible green plastic
cover on them. A suggestion to get red instrument lighting is to remove
the green covers and paint the bulbs with red nail polish. You can also
purchase all sorts of fancy coloured bulbs that will fit. I'm actually a
bit intrigued about red instrument lighting, and might paint my bulbs in
the future. You can also just remove the green covers and get brighter
My previous K100RS bike came with red instruments. Check them out, cool
shown by red arrows, are screws that hold the clear plastic end of the
wheel case on.In
my case these screws were loosened and caused the green wheel to move
enough to disengage and the trip meter to stop working. By loosening
these screws you can 'adjust' the mileage on the speedo. This is
something that I suspect was done on my bike. It might have been done to
reset it to the original mileage when a replacement speedo was
installed, or it might have been done to cheat and make the bike appear
to have less mileage than it does. In any case, it was very sloppy work
that left these screws loose.
To the right of the yellow wheel in the bottom right corner is the
speedo adjusting pot that some people have used to adjust their speedo
accuracy. I have found my speedo to be quite accurate, but yours may
read too high as many do. See the IBMWR faqs for adjustment of this pot.
order to determine the problem that your unit has, you may have to take
the speedo needle off to get the speedo's face off. I pried very
carefully but forcefully with two small screwdrivers on each side of the
needle, using a piece of stiff paper under them to keep from marring the
face. It will come off, be brave. However, you may not have to remove
the needle and face, and I recommend you do not unless you have to.
For the problem that I had, it turned out that I didn't have to remove
the face, but I had to figure out how the trip meter was activated in
order to find and fix the problem. Check the wheels for excessive play
or sideways movement. If your speedo has been working erratically, I
would suggest cleaning all the contact pins and trying it.
is a view of the speedo unit itself. You can see the speedo needle
shaft in the center. You
will need to remove the speedo needle and face to get this view. The
larger green wheel is what drives the trip meter. If you have sloppy
wheels, some people have shimmed them tighter. But, the large
translucent plastic screw you see on the far right is used to adjust the
end play of the main odometer gears. It might allow one to tighten up
wheels that have some wear and are not working if it's tightened to take
up play on the main shaft.
At least you will be able to get the unit apart now, hopefully without
breaking anything important. This unit is fairly robust, but be careful
of the flexible flat ribbon cables that flop out of the mechanism in
Follow Up -
After checking my speedo and tightening up the screws mentioned, my trip
meter started working perfectly. Unfortunately a few hundred miles
later, my speedo started working erratically. A slight tap on the
housing started it working again. This told me that connections inside
the housing were definitely the problem. So, cleaned up all the
connection pins of the main plug, and I went back into the unit and
cleaned the connection pins on the speedo board. I lightly sanded all
the pins, and worked them in their sockets a few times. Even though the
pins looked very clean, I guess some surface corrosion on the aluminum
does take place over time. It's worked perfectly ever since. I
suggest cleaning the main plug pins, and all internal connection pins
any time the instrument unit is apart. Most of the time, this will get
the unit working again for a long time.