1993 R100GS Tachometer?

[Darryl Cainey]

I went out for a short ride today on my 1993 R100GS and when I started it everything worked fine but after sitting for 2 hours suddenly my tachometer stopped working. In everyone's knowledge where would I start looking? There is now 100,675 miles on it.

 

[stevenrankin]

Wires

First place to look is the wire on the coil. Check for corrosion. After that, if you have a schematic check other spots on the wiring. As you have a GS, I can't help you much in regard to the instrument cluster system of wiring. On the other airheads, the big plug from the main harness to the back of the instrument cluster sometimes has pins corrode. LOL, I don't know if you have the same set up.

If you don't have a schematic, EME sells the best ones, color, big, PIN numbers, all on them.

As far as the tach itself, I have never had one fail so sorry. Good luck, and I hope it is simple. St.

 

[Darryl Cainey]

First place to look is the wire on the coil. Check for corrosion. After that, if you have a schematic check other spots on the wiring. As you have a GS, I can't help you much in regard to the instrument cluster system of wiring. On the other airheads, the big plug from the main harness to the back of the instrument cluster sometimes has pins corrode. LOL, I don't know if you have the same set up.

If you don't have a schematic, EME sells the best ones, color, big, PIN numbers, all on them.

As far as the tach itself, I have never had one fail so sorry. Good luck, and I hope it is simple. St.

Thanks Steve!

I do have a schematic in the Clymers book, it is a US model but it looks the same as all the rest. There are only 3 wires going to the tach, I will check the one going to the coil 1st!

Darryl

 

[stevenrankin]

curiosity

Just out of curiosity how is the tach and speedo mounted in a GS? is it in a pod like the other bikes or more difficult to get at them? LOL, the pods on the other bikes are kind of simple to get apart. Three bolts on the handlebar bracket, undo the speedo cable, the plug in the back has a screw to hold it in place. undo the screw, un plug the plug and the whole assembly is at hand. St.

 

[Darryl Cainey]

Just out of curiosity how is the tach and speedo mounted in a GS? is it in a pod like the other bikes or more difficult to get at them? LOL, the pods on the other bikes are kind of simple to get apart. Three bolts on the handlebar bracket, undo the speedo cable, the plug in the back has a screw to hold it in place. undo the screw, un plug the plug and the whole assembly is at hand. St.

The tach & speedo are mounted in holes in the dash with u-bracekts that are held with plastic nuts in the back, accessing them is not easy! I will remove the gas tank & look at the wire going to the coil first, then if necessary I will see how hard it is to look at the 3 wire block & look for corrosion. Years ago I had to remove the speedo to be rebuilt & it was a nightmare to access, I'm hoping the fix is easy please wish me luck!

Darryl

 

[guenner]

If both the odometer and the hand (right name?) don't move I would first check the cable down to the gear box.

You can check the cable by taking it off at both ends and see if you can turn the inside wire (name?) on one end and check that it follows accordingly at the other end.

It's been a while ago but I think you can unscrew the back of the speedo to expose the inside.

The odometer shaft is driven via a worm gear and the speed is transferred via induction.

My GS was a 1989 so this could be different on your 1993.

 

[Darryl Cainey]

If both the odometer and the hand (right name?) don't move I would first check the cable down to the gear box.

You can check the cable by taking it off at both ends and see if you can turn the inside wire (name?) on one end and check that it follows accordingly at the other end.

It's been a while ago but I think you can unscrew the back of the speedo to expose the inside.

The odometer shaft is driven via a worm gear and the speed is transferred via induction.

It is the tachometer that's not working, the speedometer is working fine!

 

[stevenrankin]

fingers crossed

Fingers crossed, toes crossed. Perhaps wash away the evil spirits with a German beer sacrifice? St.

 

[Darryl Cainey]

Fingers crossed, toes crossed. Perhaps wash away the evil spirits with a German beer sacrifice? St.

I will have to work on that! LOL

 

[guenner]

Oops! I better read an entry more carefully.

Indeed, there's some electronic in the tachometer. I assume you have checked the wire down to its connection at the coil.

 

[Darryl Cainey]

Oops! I better read an entry more carefully.

Indeed, there's some electronic in the tachometer. I assume you have checked the wire down to its connection at the coil.

I will have to do a continuity trace.

 

[Darryl Cainey]

I can't believe it was & I was so stupid, it was just the 15 amp fuse.

Now I have a tach that works!

I way over think things!

Darryl

 

[20774]

Take the win! Along with the learning experience! Glad things worked out.

 

[stevenrankin]

fuse?

Now that is a first for me, I have never heard of a fused tachometer. The light bulb maybe but the tachometer. Great catch and a learning thing for us as well. LOL at least you didn't tear it all apart and find the fuse later. St.

 

[Darryl Cainey]

I'm glad it was a simple fix, I should have looked there first like my wife suggested. DUH!

 

[stevenrankin]

Schematic

LOL, I am going to be diving into a schematic today. I just have to figure out why the tach was fused. I am kind of assuming it is the main power lead that is fused and it is just lumped into a system of stuff BMW figured should be fused. There are only two fuses on the bikes if I recall. St.

 

[Darryl Cainey]

LOL, I am going to be diving into a schematic today. I just have to figure out why the tach was fused. I am kind of assuming it is the main power lead that is fused and it is just lumped into a system of stuff BMW figured should be fused. There are only two fuses on the bikes if I recall. St.

Hi Steve;

There are 4 fuses on my 1993 R100GS the most forward being the one that's for the tach, I have a few spares & they are very easy to access.

Darryl

 

[stevenrankin]

learning

I had not thought the GS was so much different than its brothers, I am learning otherwise. St.

 

[pglaves]

I had not thought the GS was so much different than its brothers, I am learning otherwise. St.

I think they vary as much by year as they do by model.

 

[stevenrankin]

Gee,

So BMW went from no fuses, to two and in some cases four! Progress. St.