52 BMW 1977 R100RS Assemble and Install Seat and Cowl

The seat is the original dual seat with cowl. The cowl was painted and pin stripped. You can read about how I disassembled the cowl from the seat here.

Parts

The parts I purchased are shown below.  I replaced the rubber bumpers on the front of the cowl, miscellaneous hardware, the rear roundel and decal on the rear of the cowl, and two of the seat hinge screws.

Part #                   Description                                     Qty
52 53 1 232 904  SUPPORT – H=16 COWL BUMPER 2
07 11 9 907 639  FILLISTER HEAD SCREW – M5X10 1
46 63 7 686 746  BADGE – D=70MM 1
52 53 1 235 872  STICKER – SILVER 1
07 11 9 900 811  COUNTERSUNK HEAD SCREW – M6X10 2

Install Seat Cowl

Here is the seat and cowl before assembly.

Seat and Cowl with Installation Parts

Seat and Cowl with Installation Parts

Here are the parts I use to install the cowl to the seat pan.

Seat Cowl Installation Parts

Seat Cowl Installation Parts

On the top left and center are the washers and screws to attach the cowl to the seat pan. Top right are the cowl bumpers.

NOTE:
I show (4) cowl bumpers due to my confusion about the number needed. I only need two.

On the bottom are the rondel and R100RS cowl decal.

Install Cowl Bumpers

The two cowl bumpers go through the two holes in the front of the cowl so the face of the bumper is on the bottom of the cowl. The bumpers have a “tail” and I push that through the hole and then pull the tail all the way through the hole with pliers until it seats.

Pulling Front Bumper Through Hole in Cowl

Pulling Front Bumper Through Hole in Cowl

Cowl Front Bumper Installed

Cowl Front Bumper Installed

Cowl Front Bumper Installed

Cowl Front Bumper Installed

Attach Cowl to Bottom of Seat Pan and Grab Rail to Cowl

The phillips head bolts and washers go through the edge of the cowl into the threaded inserts in the bottom of the seat pan.

Attaching Cowl to Bottom of Seat Pan

Attaching Cowl to Bottom of Seat Pan

The grab rail attaches with four screws and special shaped standoffs.

Powder Coated Grab Rail

Powder Coated Grab Rail

Orientation of Grab Rail on Seat Cowl

Orientation of Grab Rail on Seat Cowl

This is the front bolt, washers and standoff.

Grab Rail Front Bolt Hardware Sequence

Grab Rail Front Bolt Hardware Sequence

Grab Rail Front Bolt, Spacer and Washer Orientation

Grab Rail Front Bolt, Spacer and Washer Orientation

The bolt threads into a square nut inserted into the plastic plug that goes into front end of the grab rail.

Grab Rail Front Plug with Square Nut

Grab Rail Front Plug with Square Nut

Grab Rail Front Plug with Square Nut

Here is the rear bolt and standoff.

Grab Rail Rear Bolt, Spacer, Washer and Nut

Grab Rail Rear Bolt, Spacer, Washer and Nut

Here’s how the front bolt and stand off are attached. The bolt threads into the square nut in the front end cap of the grab rail.

Grab Rail Front Bolt Head Inside Cowl

Grab Rail Front Bolt Head Inside Cowl

Grab Rail Front Bolt and Stand Off Orientation

Grab Rail Front Bolt and Stand Off Orientation

Grab Rail Front Spacer and Bolt Installed Into Front End Cap

Grab Rail Front Spacer and Bolt Installed Into Front End Cap

The rear bolt and standoff attach with a locking nut.

Grab Rail Rear Bolt and Spacer Installed

Grab Rail Rear Bolt and Spacer Installed

Grab Rail Rear Locking Nut Inside Cowling

Grab Rail Rear Locking Nut Inside Cowling

Attach Rear Pad to Cowl

I use 3M trim adhesive, aka “Gorilla Snot” to attach the rear pad to the inside top of the cowl.

3M Trim Adhesive (aka, "Gorilla Snot")

3M Trim Adhesive (aka, “Gorilla Snot”)

3M Adhesive Applied to Cowl

3M Adhesive Applied to Cowl

Rear Cowl Pad Installed

Rear Cowl Pad Installed

Attach Seat Hinges and Seat to Frame

The seat pins on the frame of the R100RS point to the rear, but on the /5 and /6 frames, the pins point toward each other. So, installation of the R100RS seat hinges is a bit different from what I show for installing the /5 seat hinges.

The two seat hinges are different and only go one way on the bottom of the seat pan. They attach with (6) countersunk pan head bolts,

Rear (Left) and Front (Right) Hinges Are Different

Rear (Left) and Front (Right) Hinges Are Different

Front and Rear Hinge Orientation

Front and Rear Hinge Orientation

I attach the rear hinge with three screws.

Rear Hinge Installed

Rear Hinge Installed

I attach the two screws on the front of the front hinge and then install the seat onto the pins.

Front Hinge Installed Using Front Screws (I added the 2nd one after I took the picture)

Front Hinge Installed Using Front Screws (I Added the 2nd One After I Took the Picture)

I install the last screw up from the bottom though the hole in frame that aligns with it using a long socket extension and an Allen socket.

I install the c-clip in the groove of the rear seat pin to keep the seat from coming off the pins.

Rear Hinge C-clip Installed

Rear Hinge C-clip Installed

NOTE:
On the R100RS the pins face to the rear and the seat can slide off the pins. This lets me install the hinges on the seat pan and then slide them over the pins. BUT, I didn’t understand that and I installed the hinges using the procedure I use on /5 and /6 seats. When I was done the seat came off the pins 🙁 Then I saw in the parts fiche there is a c-clip. Looking closely at the rear pin I see a groove for the clip. Problem solved. 🙂

Here is the seat installed.

Inspection Sticker and Tire Information Stickers

Seat Hinges Installed

Install Roundel and Decal On Cowl

The roundel is a stick on piece and so is the R100RS decal. I believe BMW intended to install the cast plate used on later model bikes but for some reason didn’t/couldn’t on the first year bikes. The decal is low class in my opinion, but I put it on to be faithful to the original design.

The decal has both a rear backing and a front protective paper film. I peel the rear backing off and install it in the rectangular cavity under the Rondel on the rear of the cowl.

Removing Rear Backing From Cowl Decal

Removing Rear Backing From Cowl Decal

Then I soak a paper towel with water and rub the front paper film to get it to release and peel it off the decal.

Pealing Paper Off Front of Cowl Decal

Pealing Paper Off Front of Cowl Decal

Here is the finished cowl with roundel and decal installed.

Rear Cowl Decal and Rondel Installed

Rear Cowl Decal and Rondel Installed