Fix a flaky or inoperative K bike speedometer

[Supershooter]

Tore my gauge cluster apart, and found a dried up gasket and rust inside. Can this be fixed? Or should it be replaced?
Supershooter

[wmax351]

Tore my gauge cluster apart, and found a dried up gasket and rust inside. Can this be fixed? Or should it be replaced?
Supershooter

Depends what you're time is worth, and if you like the mileage being correct (though you could correct the mileage on an ebay cluster if needed too).


You can very carefully disassemble those cables, and clean the contacts. Often those rusted ones get loose too. If there are breaks in the cable or circuits on the PCB, you can even very carefully solder "airwires" on to them, to restore function. I had to do it in mine.

[Supershooter]

Don't know anything about circuit boards, are there any how to's on YouTube?
I wouldn't mind fixing it myself, but don't know where to start, and am concerned about breaking it beyond repair, which I guess shouldn't be a concern since it doesn't work now.


Supershooter

[wmax351]

The soldering is going to be tough, since it's not even normal circuit type soldering.


Your best bet is to carefully try to disassemble it and clean it, I'd use Pb-catalyst seized bolt remover.

[Martin]

You can get liquid solder in a tube (conductive glue) try Jaycar. It might be easier, use a contact cleaner in conjunction with cotton buds.
Regards Martin.

[rbm]

To solder air wires on the flexible circuit strip will require a temperature controlled soldering iron that can be set to 600 *F, 63/43 solder in 0.039" diameter to control its application and lots of flux to ensure good solder flow and wetting.  That's achievable but specialized.  Better to see what you accomplish with conventional cleaning tools and products.

[Laitch]

To solder air wires on the flexible circuit strip will require a temperature controlled soldering iron that can be set to 600 *F, 63/43 solder in 0.039" diameter to control its application and lots of flux to ensure good solder flow and wetting.  That's achievable but specialized. 

Which makes me wonder if wmax351 is considering a career in vascular or neurosurgery.  :yes

[wmax351]

Which makes me wonder if wmax351 is considering a career in vascular or neurosurgery.  :yes

If I go procedural, more interested in Interventional Radiology or Interventional Cardiology. So essentially doing the soldering through the holes where the wires come out.

[Nomatch1]

Hi,
I have had a non working speedo on my 85k100 since I got it years ago. I am trying again. Wire connectors checked but the soldering iron does not make any effect. I checked the connection points at mid bike connection and did the soldering iron proximity test. The meter reads 1 and does not change the resistance. If this is having no resistence effect does it mean that the sensor is bad?
 I have cleaned it, the ring insteam rear drive is attached and spinning.
I have not seen any sensors available onlone anywhere.
I did not yet call a dealer lest I go into shock.
Any ideas for me?


Barry


in WV, 85 k100 rs, 50k,,,guessing


code 0513 I think  (not sure how to tell what month it was made)

[BrickMW]

Here is one source.


Not too bad a price, only $4.95 more than my odometer gears.  :2thumbup:

[Nomatch1]

Is there a dependable way to be sure that the sensor is dead, before buying one?


I did find a used one for $50, is this a good idea or would new be a smarter option?

[rbm]

Before springing for a new sender (which is unlikely to have gone bad), perform some tests using your PC and a program called Karamba.  My Karamba tutorial is on the K100-forum site and should serve as a test instrument for you to isolate the problem with your Motometer.  Since it's off the bike, troubleshooting will be much easier.  Building the sound card adapter cable that Karamba needs is easy.  If you can't locate the program, then PM me.

[Nomatch1]

Robert,
 Thank you for the Karamba advice. I am rounding up the parts to make my wiring rig. I will keep you all informed.
Barry

[rdivy725]

Greetings,

Got the flaky Speedo issue, got the cluster out and hit the 3 pin with Deoxit, should I use DC 4 insulating compound on it? I was def going to use it on the bulk connector...

[FlySpur]

Mine has started acting funky as well. I will try the solutions posted above and will share the update how things go afterwards.

Great thing I saw this thread.

[Laitch]

I will try the solutions posted above and will share the update how things go afterwards.

[FlySpur]

its been a while and I figured I haven't shared the update. I did clean the contact, assembled everything back again but that actually didn't help. I noticed that tacho operates normally after riding the bike for over than 20 min. However, turning off the engine and starting it back again even after short stop - and tacho starts acting up again. Well, not being able to sort it out I just ride it the way it is

[Gabriel70]

I'm still having speedo troubles---I cleaned and did a continuity checks on all the connections, including the 3 pin connector in the speedo housing (twice).  I did the soldering iron trick the speedo reads the 45ish MPH like it should, but it sets on 0 mph when I ride the bike.  I assume the sensor isn't picking up the wheel inside the final drive.  Any idea?  There are no shims on the sensor and I don't see any adjustment for it.  Back story is, the speed went from working all the time to not at all, no flaky in and out.

My issue with a flaky speedometer which eventually stoped working was due to a faulty circuit board. The thin, long board in the bottom right corner, looking at the instrument cluster with the back cover removed.
there was corrosion of the circuit board tracks due to moisture in the cluster. I replaced a faulty capacitor and the speedometer is now working.
Just my experence..