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K100 Speedometer, Odometers & Clock Not Functioning

Paul_F

RK Ryder
I taken my K100RT out for a couple of short rides this spring and despite having cleaned the rear speedometer cable twice, the speedometer, odometer, trip odometer and clock are not working. Is the fix simply a new cable or will it be the inner workings of the dash unit?

Suggestions appreciated.

In the meantime, the GPS is giving me speed readings keeping from getting tickets. :clap

Cheers!

Paul
 
It sounds like an electrical issue up at the dash unit to me. The give-way to me is the clock included in the defect. The speedo signal from the final drive should have nothing to do with the clock. I would start by disconnecting the bundle up at the dash unit and cleaning all of those contacts. Then see what is happening.
 
Paul F,

Early K bikes never had speedometer cables. The speedometer/odometer is electronic. There is an electronic pulse sensor at the final drive. It is common for this sensor or the wires between this sensor and the connector to the main bike wiring harness that is located just in front of your coolant overflow bottle to fail. It is also possible for the tip of the sensor to attract metal particles that can effect the signal.

IF the sensor/sensor wires are not bad and the odometers AND the speedometer are not working, the problem is either the speedometer drive circuit board or a bad speedometer head. If the speedometer works but the odometers don’t, the problem is bad odometer gears.

Try pulling the pulse sensor and cleaning the tip. Then pull it out of the bike all the way back to the connector by the coolant overflow bottle. Then take an AC soldering gun or iron and hold the gun or iron 1/4” away from the tip of the sensor while wiggling the wire (especially around the connector) with the key and kill switch in the run position. If the speedometer needle moves at all during this, the problem is a broken sensor wire. If the wires make solid contact, the needle will remain solid somewhere around 45 mph if you are in the US or a country that has 60 cycle AC current. 50 cycle current will cause the speedo to read somewhat less.

Your clock not working is either a blown #3 fuse or the clock module itself. Or it could be the clock power pin in the connectors to the back of the instrument cluster I guess.



:dance:dance:dance
 
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Paul G.,

It is possible that there is a problem with pin #1 (power from fuse #3 directly to the clock). Pin #1 is the top pin on the left connector (facing the back of the cluster).

AND pins #22 & #23 (speed pulse sensor wires to speedometer). Pins #23 and #22 are the second and third pins from the bottom of the right connector.



Paul F.,

Are there ANY other functions on the dash that are not working properly?..






:dance:dance:dance
 
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Paul G.,

It is possible that there is a problem with pin #1 (power from fuse #3 to the clock). Pin #1 is the top pin on the left connector (facing the back of the cluster).

AND pins #22 & #23 (speed pulse sensor wires to speedometer). Pins #23 and #22 are the second and third pins from the bottom of the right connector.



Paul F.,

Are there ANY other functions on the dash that are not working properly?..
:dance:dance:dance

The rpm’s, the brake light and the choke light are all functioning. I haven’t ridden the bike far enough this spring for the low fuel to light up.
 
Turn indicator dash lights, neutral light, gear position indicator, high beam indicator, bulb check light, oil pressure light, charge light, backlights?


I just remembered, try turning on your turn indicator and drive with it on. If it doesn’t cancel before around a half mile or so at over 40 mph, there is a really good chance that the problem is the speed sensor or the wire up to or just past the connector by the overflow bottle.

Do the test with the soldering gun/iron.



:dance:dance:dance
 
Turn indicator dash lights, neutral light, gear position indicator, high beam indicator, bulb check light, oil pressure light, charge light, backlights?


I just remembered, try turning on your turn indicator and drive with it on. If it doesn’t cancel before around a half mile or so at over 40 mph, there is a really good chance that the problem is the speed sensor or the wire up to or just past the connector by the overflow bottle.

Do the test with the soldering gun/iron.

:dance:dance:dance

The above work. However the turn signals are not automatically turning off.

I will check the items that you and Paul have suggested today.

Thank you.
 
Paul,

Check the fuses first and see if that is the problem with the clock. Things are easier to troubleshoot if you only have one problem.




:dance:dance:dance
 
I changed the fuses that control the dash unit; all looked well worn. As well I separated the wire near the coolant overflow bottle which connects to the rear wheel, although I assume I would need an electrical spray to clean the terminals. I’ll pick up a can. On the plus side, the clock has been keeping the correct time for over twelve hours and all the indicator lights come on, with the exception of low fuel (tank isn’t near empty).

On the downside, neither odometer works, nor the speedometer and the automatic shut off feature of the turn signals is not functioning. As well, now the brake light indicator remains on.

My mechanical abilities are extremely limited. I will most likely use the GPS for mileage and speed for now and when the spring bike rush is over, take it to a dealer. With my history, I have the ability to make things worse when I attempt repairs.

Thank you Paul and Lee98 for your patience and advice.

Paul
 
Your brake light indicator is on (if you just checked it in the garage) because you didn’t cycle both the front brake lever and the rear brake pedal OR you actually have a bad tail light, brake light, or front or rear brake light switch.

Did you do the soldering gun test?


I would probably just put a good speed sensor in it (but that’s because I have several of them available to me).



:dance:dance:dance
 
Since neither speedo or trip meter operates there is a more than likely chance that the gear train that runs both has given up. The original gears tend to crack and just fall apart over time. I have heard that the grease used at the initial assembly causes the plastic gears to deteriorate and fail. A company called speedometergears.com makes replacements out of better materials that don't require lube. The replacement operation can be quite daunting to someone who is not experienced. Maybe if you are lucky you have a speedometer shop close by.

Frank
 
Since neither speedo or trip meter operates there is a more than likely chance that the gear train that runs both has given up. The original gears tend to crack and just fall apart over time. I have heard that the grease used at the initial assembly causes the plastic gears to deteriorate and fail. A company called speedometergears.com makes replacements out of better materials that don't require lube. The replacement operation can be quite daunting to someone who is not experienced. Maybe if you are lucky you have a speedometer shop close by.

Frank


The gears only drive the odometers. They are driven off the speedometer. USUALLY, when one of the teeth in the gear train breaks, the speedometer continues to work.

The most likely cause of the OPs problem (especially given that the clock problem was not related) is a bad speed sensor.



:dance:dance:dance
 
The gears only drive the odometers. They are driven off the speedometer. USUALLY, when one of the teeth in the gear train breaks, the speedometer continues to work.

The most likely cause of the OPs problem (especially given that the clock problem was not related) is a bad speed sensor.



:dance:dance:dance

You are correct. I recently went through the speedo gear problem on my RS.

Frank
 
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