1977 R100RS VIN 6180422 Rebuild Complete

[brook.reams]

Folks,

I finished a rebuild of this bike on July 21, 2017. I wrote-up a description of how I assembled the bike starting with the frame and ending with the gas cap. There are pictures and a short video of the completed project a the end of this write-up.

00 BMW 1977 R100RS Assembling The Bike From the Frame Up
I documented the complete project here:

1977 BMW R100RS Rebuild: Project Index
I plan to ride it from Denver,CO to the 40th anniversary rally hosted by Todd Trumbore in Harleysville, PA, September 14-16, 2017.

Here are some pictures of the finished build.

BMW Roundel Installed by Brook Reams, on Flickr

Rear Cowl Decal and Rondel Installed by Brook Reams, on Flickr

Inspection Sticker and Tire Information Stickers by Brook Reams, on Flickr

Dash and Instruments Installed by Brook Reams, on Flickr

Finished Bike-Carburetor by Brook Reams, on Flickr

Clear View Wind Screen Installed by Brook Reams, on Flickr

Finished Bike-Right Front by Brook Reams, on Flickr

Finished Bike-Right Rear by Brook Reams, on Flickr

Finished Bike-Rear by Brook Reams, on Flickr

Fairing and Body Work Installed by Brook Reams, on Flickr

Finished Bike-Right Front by Brook Reams, on Flickr

Custom Steering Damper Courtesy of Bill Lambert by Brook Reams, on Flickr

At the Coffee Shop For a Test Ride by Brook Reams, on Flickr

Best.
Brook Reams.

[jim in the north]

WOW!
All I can say is congratulations on such a comprehensive write-up on the restoration of this motorcycle. Your dedication to your craft of thorough documentation of the process is commendable. Thankyou for your effort. We will all benefit from reading this information. Clymers writers; take a lesson from Brook.

[brook.reams]

Thanks Jim. I hope this material helps others who want to do any of this work.

Best.
Brook Reams.

[schrader7032]

Brook -

I didn't know where to address this. I was reading some backlogged emails from the Airlist when you first began this project. Yeah, I'm that far behind!

At one point, you were questioning the masses how to orient the fork tubes with respect to the holes in the tubes. At first you thought just putting them pointing back towards the bike would be the way to go. Tom Cutter offered up a way to find the high spots in the tubes rolling around a flat surface and using that to your advantage when it came time for assembly. That would reduce stiction.

I was wondering what did you finally do?

My reason for bringing this up is from a structural stress standpoint. I wished I could have commented at the time, but since I wasn't actively reading the digest emails at the time. My input would have been to put the holes either pointing at each other or directly opposite meaning pointing out the sides. The reason is that the tubes are undergoing flexing fore-aft. As the tires hit imperfections, as you get on the brakes, the tendency is to bend the tubes fore and aft. Think of the bike on the centerstand with the front wheel off the ground...then grab the sides of the axle with each hand and push the axle parallel to the ground. This is the type of bending going on.

For a tube bending this way, the maximum bending stresses are going to be either along the front surface or the trailing surface. At the mid point of the tube, or in this case, the side of the tube, the bending stress is zero. Typically, the front side will go into tension while the exact opposite side will essentially be compression of the same value, just negative from the front side.

The hole in the tube creates a stress concentration...typically circular holes cause a factor of 3 rise in stress at the very edge of the hole. If there should be an imperfection there, the local stresses become three times higher and a crack can form and eventually grow.

For this reason, you do not want the holes to be on the front or the back. They should be either pointing at each other or pointing away from each other to the side.

I would loved to have had that input to the discussion but missed my opportunity.

Thanks...

[spo123]

I have not visited this site in a few months.....
Brooks,
You have created a fabulous reference resource that will "live forever".
Absolutely first class with the detail and excellent photos.
On behalf of myself AND future generations of Airhead owners and enthusiasts, THANK YOU, SIR!
WELL DONE!

Ride Fast and Safe!
spo123