Airhead Transmission Ratio Swap

In early 2002 I learned that it was possible to change the ratios of both first and fifth gears in the GS transmission by swapping out gears. Surprisingly, only one of the gears of the respective pairs need be changed. I called Cal BMW and Ozzie's BMW for pricing, and found that each wanted almost $300 per gear for the parts, plus labor to do the swap. That was prohibitively expensive,and the idea went onto the back burner. Several months later I was leafing through the back pages of a Classic Bike magazine Gene had loaned me (it was the issue that profiled Norton's Production Road Racer from the '70s), and I noticed an advertisement from S. Meyer in Hillesheim, Germany advertising BMW parts. Having previously dealt with many parts suppliers in Great Britain, I composed an email to S. Meyer inquiring about the gear swap. In a few days I received a reply quoting the following prices: 6 % lower 1st gear Euro 90 18 % lower 1st gear (Set 2 gears) Euro 250 6 % quicker 5st gear Euro 120 10 % quicker 5st gear (Set 3 gears) Euro 620 At the time, a Euro was going for about $.95, so these prices represented a vast departure from what was being quoted locally. The gears were made by a company called Kaiser. I FAXed a copy of my Visa charge number along with a note explaining what I required (6% lower 1st gear and 6% quicker 5th gear) and in about 3 weeks the parts were sitting on my front porch. In the mean time, I started local inquiries for someone to do the installation, along with a general reconditioning of the transmission: replace all bearings and bushings, replace shifter spring (prone to breakage), etc. One of my buddies suggested I call Bob Grauer, who seemed quite knowledgeable and willing to undertake the work. I told Bob the parts were on the way, and that I would contact him again when they were in hand. When the gears arrived, I emailed Bob asking when I could bring the transmission by, and he indicated, by reply email, that he was no longer interested in doing the work. I called him, asking for some elaboration, but all he would say is that he wouldn't do the job, and that I shouldn't have any trouble finding someone else. I still have trouble adequately expressing my shock, dismay, and anger at this behavior. Absolutely unprofessional to put it mildly. But enough said. Gene suggested I try Dave Gardner at Recommended Service, an independent mechanic he'd been using for years for tires and, more importantly, transmission work. Dave was interested, but was concerned about the quality of the parts until I mentioned they were sourced from S. Meyer. Dave was familiar with the company, explaining that they had partnered with BMW in the '40s, '50s, and '60s to assemble some of the most successful race bikes in the company's history. We set a date for the next Friday, and I got busy pulling the transmission from the GS. I won't go into the removal process here, except to say that it was very nice that BMW uses the frame to support the center stand on the GS, and unlike the K series, it isn't necessary to rig up some sort of auxiliary support for the rear of the bike when pulling the tranny. The job went very smoothly, and after three or so hours I had the transmission on the bench. I hate working on dirty parts, and I figured Dave would appreciate getting a clean transmission case. I Gunked it, first sealing off the speedo drive hole with duct tape. After drying, I went after the corrosion on the top (where the air box sits) with a brass brush and contact cleaner. It never did get to silver white, but the crusty white deposits were removed.
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