The summer of 2015 I got to ride my R75/6 across the country from San Jose to New York with my husband, Paul. I didn’t have a neutral light the whole way- though everything else on my 40 year old bike worked like a charm- it even waited til it was home in the garage, for the original rotor to go. I got this particular /6 as a winter project in 2013. I did a fairly complete renew on it that winter. That year and every winter since, I’ve had to open up the instrument pod and fix something. The winter of 2015-16 was no exception, and I was pretty frustrated by it. Paul said “we should just make this PCB new with leds.” (He’s an electrical engineer) And KATDASH was born. We’ve tried to design and build this unit to be as durable as the Airhead. Hopefully, you’ll get another 20 years out of yours.
Happy Trails- Kat
Beartooth Pass- 2015
How we got started:
As you know, the original light bulb frame for the instrument pods is NLA. It’s been NLA longer than I’ve been an Airhead. Many of us have been patching these for years, or sending them to various shops to have them patch or replace the light board with a good used unit. I’m an Architect- I can design a steel beam to hold up a house, and I’ve got a cad system, but I don’t do electricity. Paul is a professional EE and does pcbs & software for a living.
We began in November of 2015 with version 1 (of 3) of the instrument pod- not because it’s version 1, but because I ride a R75/6. We started by 3D modeling the oem plastic bodies and getting them 3D printed. Paul designed a schematic with leds and the required resistors based on the original /6 flex circuits. He referenced Snowbum’s emergency GEN resistor design for the early prototypes. And there were several email exchanges with Robert during later testing with bikes. Then we made paper test pcbs. Lots and lots of paper test pcbs with leds & resistors glued on, and wired up with 32ga hookup wire. We tested light brightness, we tested light locations (for the instrument gauges). We did several different versions of the GEN excite current resistor design and did MORE test boards. Then we took those test boards to a Rally, and tested them on multiple bikes to get real rpm readings on the GEN circuit light.
We built real prototypes with actual manufactured flex circuits, and I had 2 different molds made for the plastic bodies. There was nothing remotely close to the original connector pins- so I have a local machine shop make those for me- and I re-designed the pin collar & installation to reduce stress on the flex. We sent these actual flex prototypes to Airhead pros and other riders around the country for 5 months of actual road testing for the first summer season of our startup business in 2016. We found some unexpected bugs- the oem Hella turn signal relay leaks voltage; and some surprising bugs- it’s amazing just how small of a ground leak (especially riding in the rain) will light an led.
So Paul fixed the bugs, and we sent out the flex for actual production manufacture. Then I ordered 1000 parts from each body mold, and 20,000 pins from my machinist. Each unit is hand assembled, by us- with the tiniest torque screwdriver ever- in my office. We plug each one in at assembly and make sure it’s operating properly, then they are carefully packed in static guard bags and bubble wrap for shipping. We built these to be the highest quality boards we could design- a light board I would, & have put in my own bike, and never have to open the instrument pod again. I hope you will be pleased with the performance and quality of yours.
Wishing you many happy Airhead miles ahead-
by email: Kat
by snail mail: 64 Harmony Road, Northwood, NH 03261
office phone: 603. nine four two. 6761. This is a land line- so no texts.
BMW Airhead Shops that stock & install KATDASH lighting units:
USA: Martindale Motorcycle Works Texas
Nickwackett Garage Vermont
Bob’s BMW Maryland
Motorrad Elektrik Alabama
Airhead Adventures California
A.C.E. Vintage Motorcycles Florida
Boxer 2 Valve North Carolina
Hermy’s BMW PA
Barnsley Motor Works Roopville, GA
CJ Motorrad Deephaven, Minnesota
Britts and Beemers Idaho
Queen City Moto Ohio
Re-Psycle BMW Parts Ohio
Steve’s Bavarian MC Service Oregon
Bob’s BMW Maryland
Bombar’s Beemers North Carolina
MAX BMW NY, CT & NH
Snowbums’s Technical Pages. You have to scroll all the way to the bottom to get to the technical article list link. Wordy & in depth, but a goldmine of information for Airheads. Snowbum’s BMW Technical Information
Airheads Beemer Club (ABC): Lots of friendly help, local tech days, and new and old Airhead fanatics at this Club. Members get a monthly newsletter. http://www.airheads.org/
Instrument Repair: Terry Vrla in Oregon. If you have an Airhead, you have a mechanical speedometer that needs service. Just think- there’s 30 year old dried up grease in there. Preempt any trouble and service your instruments. If one of your instrument needles starts to swing back and forth erratically- disconnect the cable immediately. If you wait- it will self destruct, and will be more difficult to repair. Emailt Terry at: Terry Vrla