Odometer Gears

[stokester]

This spring I decided to do a refresh on my '93 K75S in anticipation of my first summer of retirement and more time riding.


So I've replaced the brake lines with a Spiegler stainless steel kit and the rear shock with a YSS unit.  More on those later.


While updating my maintenance log book I noticed that the odometer mileage had not changed since my last update a couple of months ago.  The trip meter has not worked at all and would not reset since I bought the bike so I've used a bicycle computer to gauge my fuel stops.


Research on this site brought up the info I needed to remove the instrument cluster and I figured out the steps for disassembly to access the odometer gears. 


When looking up odometergears.com I found out they are located just down the road in Newport News VA so I contacted Jeff Caplan to see if I could stop by and pick up a set.  I stopped by his shop and he offered to show me how to replace them.  As you can see the orange, green and small drive gears are chipped while the white one was not.  Removing the large gears is quite easy but the small drive gear is pressed on with a brass bushing requiring the use of a pliers to deform it from the motor shaft.  A firm squeeze with a pliers from each side allowed it to slip off easily.  Installation requires removal of the cover off of the motor so when you press it on the shaft can be blocked to prevent motor damage from pressing the new gear with bushing on the shaft.  It is key that it not be pushed in too far so the shaft can move in and out slightly.  These procedures are explained quite well in Jeff's instructions on the site.


He showed and explained to me that the gear problem is not particular to BMWs or any particular car but really a VDO and in our case MotoMeter issue.  He makes gears to fit many vehicles.


The gear replacement fixed the odometer and trip meter but the trip meter still does not reset.  When we looked at the reset shaft there was no obvious problem but without a spare I elected not to disassemble it any further to diagnose the reset, the bike computer works quite well.

[Chaos]

My mileage dropped below 20mpg before I figured out it was the odometer gears.  I should spring for odometergears, I've just cannibalized old K pods for almost nothing. Ready for my 3rd set whenever I feel like pulling it out again. 

[stokester]

My mileage dropped below 20mpg before I figured out it was the odometer gears.  I should spring for odometergears, I've just cannibalized old K pods for almost nothing. Ready for my 3rd set whenever I feel like pulling it out again.

I thought about doing something similar but know that cannibalized replacements are all about the same age and I could either pay now ($85) for a permanent fix or just prolong the inevitable future failure.  I'm now in retirement and want to ride this K75S forever, any permanent fix is an add to my riding time.  :riding:

[The Mighty Gryphon]

I wonder if those gears are made that way to make mileage tamper-proof.  Someone tries to screw with the odometer and it doesn't work anymore. 

I have been involved in making plastic gear sets, and the materials commonly used, nylon and acetal, are amazingly tough.  Think of the speed reduction gears in power tools.

[Martin]

The local instrument guy in south Brisbane where I bought my replacements told me not to lubricate the gears. He said lube actually accelerates degradation of the gears. I did not grease on reassembly but I later thought I could maybe have used a silicone grease.  :dunno
Regards Martin.

[stokester]

The local instrument guy in south Brisbane where I bought my replacements told me not to lubricate the gears. He said lube actually accelerates degradation of the gears. I did not grease on reassembly but I later thought I could maybe have used a silicone grease.  :dunno
Regards Martin.

From OdometerGear's FAQs...
#8 - Why did my original gears fail?The original material used to manufacture your odometer gears was urethane and lubricated with petroleum grease. The grease overtime turns the gear into a waxy material and fails. Even the original replacement gears were packaged with grease and changing the new gear to a waxy substance while sitting on a shelf waiting to be installed.
#9 - Will your gears last longer than the original?We had the help of speedometer shops from across the country when researching a material that will be a permanent repair for your vehicle. We found and manufacture our odometer gears using an acetal plastic with the trade name CelconŽ. This material has excellent resistance to moisture, a wide range of chemicals, oils, greases and solvents. It also offers high strength and rigidity over a broad temperature range with low wear and is self lubricating by design. We offer a lifetime parts warranty on our products and are confident that the products we manufacture and sell will give you years of trouble free service.
#10 - Do I need to apply grease to my odometer gears?Grease is not recommended unless it is stated in the how to instructions (Mercedes-Benz 126 chassis only to help to quite any noise that the odometer may cause). Our gears are made using Celcon and has graphite in the material so they are self lubricating, so no further lubricant is needed.

[Chaos]

I wonder if those gears are made that way to make mileage tamper-proof.

No, I've found it pretty easy to reset the mileage on K bikes and other brands when replacing speedometers.

[Harrowbmw]

I'm kind of jealous.  My instrument pod gears need replacing and after finally and accurately counting the teeth, I've discovered it will cost US$85 to purchase them, I'm ok with that, however, another US$86 to send such a small package to Australia.  I've had to pass.

[schrocketeer]

Could you roll the tripmeter knob before it was installed in the instrument cluster housing?
I did my odometer/tripmeter a few weeks ago. I had trouble with the circlip holding on to the inside part of the reset knob shaft. Yeah, I had to disassemble to get that back on. Well twice to disassemble, since I forgot the spring that goes on the inside the first time. Then I had to re-do another time for that shaft circlip.

BTW, you can roll Motometer gears to change the odometer mileage. Gently with fine tipped, flat head screwdriver. On my '85 K100 RT, I added in the 3000 miles my friend the previous owner estimated, after the odometer quit.

Is there an Australian reseller of "Snaporaz" gears? I was going to order a set from Italy, but they had a re-seller here in the US. Maybe you can contact them from the listing at https://www.ebay.com/itm/195733182132?_skw=bmw+motometer+gears&itmmeta=01JX0X6AF5ER5PMNTVV1A2NJ8E&hash=item2d929b56b4:g:9UwAAOSw0UBkRpf6&itmprp=enc%3AAQAKAAAA8FkggFvd1GGDu0w3yXCmi1f9kd3DiJAIS1%2BGnDOQ%2BgabCJhPSKU6%2F65Nto0OfKlQqN2fCq7t1QnVV12byZh1DcT1VcqTRZdsOBUo2vGm2J0DCPEeUbMwcNfrmkDmWbbNol1hn1yspRRcRIEboMp04yp25z1o8TQhej2ydZ%2F65eMajwHxb%2FAuJE9eMBIZwEHOLP0K7Uc3jh9QfligSGvEDfUM2ew3A3IrBKLV9laW%2BuD1DOqcRoU1P96EQw3fePSYbTlDI49E%2FOrUNO6SlEBND2kt0SuPv0vDInWS9LyPPHLb8OP6UloC%2BvdqWWt%2BmkhgLA%3D%3D%7Ctkp%3ABFBM4KeZnehl

[stokester]

Could you roll the tripmeter knob before it was installed in the instrument cluster housing?

No, it was that way when I bought the bike.


I do have a donor instrument pod to repair whatever is wrong with the tripmeter reset but the bicycle computer works just fine.