Gonzo (my 1977 R100RS) and I are going to be on the road again on our way to Todd Trumbore’s home where he is hosting his third airhead 40th anniversary celebration of bikes designed by the legendary Hans Muth, on September 19-22, in Harleysville, PA. (Yes, an ironic location for a BMW airhead rally 🙂 ) This time Todd is celebrating 40 years since the introduction of the iconic R80 G/S and the R65LS models in 1979. Once again, Hans will be in attendance along with a notable list of other airhead and motorcycle legends who will be speaking. You can see the details here:
The first rally Todd hosted was in 2014 for the R90S and the second was in 2017 for the R100RS, which is the rally Gonzo and I first attended. Even though my garage does not yet include an R80 G/S or R65LS, Todd was happy to let me attend the festivities despite riding “only” an RS.
The R80 G/S and R65LS are the last two designs Hans developed for BMW before starting a design studio, Target Design, with some friends, Jan Fellstrom and Hans-Georg Kasten. One notable design from the Target Design studio was the Suzuki Katana in 1980. I find the lines of the R65LS and Katana are similar, as if Hans extended the design vocabulary the BMW R65LS and to the design commissioned by Suzuki for the Katana.
Suzuki Katana-To Me, It Echos The Design Vocabulary of the R65LS
When Gonzo and I went out in 2017, we had an adventure when the shift cam retaining circlip in Gonzo’s transmission came off the shaft. The BMW dealer I ordered it from supplied the wrong size circlip and I was not attentive enough to notice. Gonzo and I ended up being transported to the rally hotel by Scott Mercer with assistance from Tom Gaiser, and Keven O’Neil. Tom Cutter, at Rubber Chicken Racing Garage, one of the best airhead transmission re-builders, was a speaker at the rally and put Gonzo on his trailer while I followed him to his shop riding his “most excellent” R100 “Fake S” bike. He took apart the transmission on the Sunday after the 2017 rally while I watched and assisted with cleaning parts, and I was back on the road that Monday. Here is the story of my adventures going to the 40th anniversary of the RS rally in September 2017.
Although Gonzo and I are very appreciative of Tom’s generous assistance. we plan to avoid imposing on him again on this trip. 🙂
Since I \didn’t complete the entire trip last time in 2017, I am going to take the same route out and back this time. Somehow that seems appropriate.
Gonzo now has “matte” clear coat, which is correct for the 1977 RS bikes, but due to my failure to communicate with my painter, he was repainted with gloss clear coat back in 2017 when I did the restoration. He is also sporting the commemorative badge Todd provided to the participants of the 2017 R100RS rally. I think it’s a very nice touch and a lot classier than the cheap decal BMW originally used on the cowling in 1977.
This bike has a front master cylinder that is integrated into the Magura throttle assembly and a rear Brembo master cylinder. All three calipers are Brembo F-08 series with dual 38 mm pistons. I disassembled both master cylinders and inspected them. I repainted and rebuilt the rear master cylinder using a Brembo rebuild kit. Unfortunately, I found the front Magura master cylinder bore and internals were badly rusted and pitted, so I had to replace the front master cylinder rather than rebuild it. Even though I didn’t have to rebuild the front master cylinder, I show how you rebuild it and the rear master cylinder in this document.
I disassembled all three calipers, inspected them and found they were not corroded or pitted so I repainted and rebuilt them using a Brembo caliper rebuild kit. The same kit is used on all three calipers. You can see how I did that work here:
I’m going to powder coat the swing arm, and the bike has 83,000+ miles on it. So I am removing the swing arm bearings and will replace them.
BMW used two different style bearings on the airhead swing arm: an unsealed 30203 bearing that was changed part way through the 1981 model year (01/1981) to a sealed bearing, FAG 540619. Changes in the swing arm bearing assemble were made at the start of the 1981 model year (09/1980) when the pivot pin was shortened and the dust cap changed to accommodate the 30203 bearing with the shorter pivot pin. Then in January 1981, the sealed bearing was added with it’s included dust cap.
I’ve removed the 30203 bearings before using the tool from Cycle Works.
Cycle Works Bearing Puller Kit
But it won’t fit inside the captive sleeve of the sealed bearing. And I can’t remove the inner race without a puller as it is captive due to the sealed bearing design. So I bought a set of blind bearing pullers for less than $60.00.
This kit has a slide hammer and a set of puller legs when more force–that will be required for the outer race extraction–is needed. There are various size expanding sleeves that cover a wide range of bearing diameters, so I bought it.
Less Than $60.00 Blind Bearing Puller Set
I made a collar so I could use the blind puller to remove the outer race. It cost me $7.00 in parts. I used it to remove on of the outer races and it worked nicely. So, if you have a set of blind bearing pullers, or buy a set like I did, you can remove the outer race by making your own collar.
Washer Rests On Edge Of Tube That Holds The Bearing
Blind Bearing Puller With Jaws Ready To Extract Outer Race
FAG Sealed Bearing Disassembled During Removal
Here is a link to the documentation I wrote about how I did this work.