00 BMW 1973 R75/5 Final Assembly

I’m ready to finish assembling the bike. Here is what is left to do

  • Seal the gas tank filler neck and petcock spigots
  • Assemble the gas tank and mount it,
  • Attach the rear fender,
  • Attach the tail light and rear turn signals,
  • Attach license plate bracket and rear reflectors
  • Attach front fender
  • Attach the seat
  • Attach (and it turned out, repaint for the 3rd time) the side covers,
  • Add the new tool kit and tire pump,
  • Check the tire pressure
  • Check that all oil and lube is added (I did that earlier, but it’s good to be DAMN sure)
  • Take some “glossy” pictures of “Grover” all back together again

Seal Gas Tank Filler Neck & Petcock Spigots

I want keep the filler neck and petcock spigots from being a weak link in the paint job. So, I decided to coat them with epoxy to seal them. In particular, at the neck of the spigots where they are brazed into the bottom of the tank, it’s easy for a crack to develop in the clear coat and fuel to seep under the paint causing a blister or bubble.

I use 5 minute epoxy. I use the acetone to quickly clean up any epoxy that goes where it shouldn’t and if the epoxy is too thick to brush on, I can add a few drops of acetone to thin it. I apply the expoxy with a $0.99 1 Inch brush from my Home Depot store.

5 Minute Epoxy for Sealing Tank Filler Neck and Petcock Spigots

5 Minute Epoxy for Sealing Tank Filler Neck and Petcock Spigots

I don’t want to ruin the paint. I mask off the top of the tank with panter’s plastic and masking tape being sure it covers the top completely. I use just the masking tape to tape off the paint around the petcock spigots

Protecting the Tank

Protecting the Tank

Masking Gas Tank Petcock Spigot for Epoxy

Masking Gas Tank Petcock Spigot for Epoxy

The filler neck has some rust spots from the wet sanding. I use some rust remover and apply it with a tooth brush. Then when it has worked, I use a wet blue shop towel to remove all the rust remover.

Tank Filler Neck with Rust From Wet Sanding

Tank Filler Neck with Rust From Wet Sanding

Then I mix up about 3 inches of expoy and paint it on the tank filler with the 1 inch brush. It’s a warm day and the expoy is easy to brush so I don’t need to thin it with acetone. Here is the filler neck after the epoxy has set for 20 minutes.

Epoxyed Tank Filler Neck

Epoxyed Tank Filler Neck

After the filler neck epoxy is hard, I turn it over and I paint more epoxy on the petcock spigots. I extend the epoxy just a little over the edge of the paint to seal it off. When the epoxy starts to thicken in 2 to 3 minutes, I gently peel the masking tape off being careful not to smear and epoxy on the paint. Peeling the tape early prevents cracking the epoxy when I peel it. I let this dry for 20 minutes.

Epoxy Around Neck of Gas Tank Petcock Spigot

Epoxy Around Neck of Gas Tank Petcock Spigot

Assemble Gas Tank and Attach

The emblems, gas cap and petcocks need to be attached to the tank. The emblems have a rubber gasket under them and attach with two screws.

Mount Badges

Before I mount the badges, I use some Griots #4 polish on the original one to remove any minor scratches and to make it shine.I bought a replacement badge for the one that was damaged.  I also remove the rust from the screw threads with some “00” steel wool.

Tank Badge, Gasket and Screws

Tank Badge, Gasket and Screws

Attach Gas Cap

The gas cap attaches using a pin with serations on one side.

Gas Cap and Hinge Pin

Gas Cap and Hinge Pin

I use a pin drift to gently tap the pin in and seat it.

Use Drift to Set Hinge Pin

Use Drift to Set Hinge Pin

It latches tightly over the new epoxy covering.

Attach Rubber Knee Pads

I use “Gorilla Snot” which is 3M weatherstrip adhesive to attach the rubber knee pads.

NOTE: And, the 3M weatherstrip adhesive failed on a 94 F day. I had received a note from someone that this may happen. Fortunately, the knee pad fell off in the parking lot at work and I retrieved it. The adhesive was hard in some places and still soft in others. Based on this, I DON’T recommend this adhesive for attaching the knee pads.

I removed all the 3M weatherstriping adhesive with lacquer thinner and a clean towel, which took quite some time to get it off the tank. Then I apply silicone seal liberally to the pads, then I position them on the tank and keep them positioned with masking tape until it set.  I use a liberal amount of silicone seal, but keep the bead about 1/2 inch from the edge of the pads so when I pushed it into the tank, I got almost no silicone seal past the edge. The little that did squeeze past the edge was easy to remove with a the edge of a Popsicle stick. So far, so good.

3M "Gorilla Snot" Weatherstrip Adhesive-DID NOT HOLD :-(

3M “Gorilla Snot” Weatherstrip Adhesive-DID NOT HOLD 🙁

So, I am optimistic that the silicone seal is the way to go. The Windjammer fairing uses it to stick the metal headlight bracket to the painted fairing plastic and that held for 42 years, so I expect it to work for the tank knee pads.

Mount the Gas Tank

It is a very tight fit to get the gas tank on. I put soft rags around the neck of the tank to protect the paint. At the rear of the tank, the sides of the tank will gouge the frame tubes if I’m not careful. If I pull the neck of the tank forward so it is over the steering head chrome cover there is enough room at the rear of the tank to pass by the frame tubes. Then I gently pull the tank to the rear so the front of the tank that goes under the steering head chrome cover can pass over the chrome cover. Then I gently push the tank forward to seat it on the front rubber tank mount and align the mounting holes in the rear of the tank over the studs. I attach the tank at the rear with the two wing nuts that you can see in the picture below.

Tank Mounted with Wing Nuts on Rear

Tank Mounted with Wing Nuts on Rear

Attach the Petcocks

The petcock on the left has the choke cables behind it. It’s common for them to cut into the back side of the petcock. I use a plastic tie wrap around the two choke cables next to the choke assembly to help keep them away from the petcocks. But, this one has deep grooves in it. I use some 5 minute epoxy to fill them in. After I mix it up, I wait a minute or so until it starts to thicken before I apply it with a popsicle stick.

Epoxy Repair to Back of Left Petcock

Epoxy Repair to Back of Left Petcock

I insert the petcocks being sure the two plastic tubes are in the correct holes as shown in the picture below.

Rebuilt Petcock

Petcock Showing Correct Orientation of Plastic Tubes

There is a red gasket that goes inside the petcock around the two plastic tubes. You can see the gaskets in the middle of the picture below.

Rebuild Kit Left-to-Right, Jet Needles, O-Rings, Needle Jets, Throttle Plate Screws, Float Needles, Float Hinge Pin

Red Gaskets (in the middle) Go Inside the Petcock Around the Plastic Tubes

The nut has threads on both sides and is a reverse thread on the tank and a normal thread on the petcock. I start the nut on the petcock, then attach the nut to the gas tank petcock spigot and tighten while holding the petcock so the black ring on the front faces forward.

Here is the assembled gas tank mounted on the bike.

Gas Tank Assembled and Mounted

Gas Tank Assembled and Mounted

Attach Rear Fender

Before I mount the rear fender, I remover the rear wheel so I can get to the mounting areas.

Remove Rear Wheel to Mount Rear Fender

Remove Rear Wheel to Mount Rear Fender

The rear fender mounting hardware is shown below.

Rear Fender Mounting Hardware

Rear Fender Mounting Hardware

In the center, at the top, is the hardware to mount the front of the rear fender to the frame using holes below the battery. The metal tubes are offsets to position the fender in the frame. The bottom two rows of hardware mount the fender to the rear seat frame and use a steel strap inside the fender with bolts, nuts and rubber gaskets.

The picture below shows the rear mounting bolt and spacer inserted in the hole below the battery.

Lower Mount with Standoff for Rear Fender

Lower Mount with Standoff for Rear Fender

The rubber gasket goes against the frame and the steel washer goes between the end of the spacer and the rubber washer.

Rear Fender Lower Mounting Hardware Orientation

Rear Fender Lower Mounting Hardware Orientation

I tighten up the bolts and nuts until they are snug. The bolts are locking bolts and I don’t want to put too much force on the fender or it will crack.

Rear Fender Standoffs Mounted to Lower Rear Fender

Rear Fender Standoffs Mounted to Lower Rear Fender

The top mounts for the rear fender are just behind the top cross brace at the back of the tool box and at the rear of the subframe. Both mounts use a steel strap on the inside of the fender.

Top Mounting Strap Inside Rear Fender

Top Mounting Strap Inside Rear Fender

The rubber gasket goes against the fender with the steel washer and locking nut on top. Again, I tighen the nut until it is snug to avoid cracking the fender.

Rear Fender Top Mounting Hardware Orientation

Rear Fender Top Mounting Hardware Orientation

Here is the mounted rear fender.

Rear Fender Mounted

Rear Fender Mounted

Attach Tail Light and Rear Turn Signals

The tail light and turn signals attach to a chrome bracket that attaches to the rear of the rear fender. The original chome peeled from the bracket and I bought a new one. I have to install the wiring for the turn signals into the new bracket.

Old and New Turn Signal Bar

Old and New Turn Signal Bar

I take note of which color wires go to which side of the bracket so I will replace them on the correct side of the bracket. There is a brown ground wire to each turn signal.

Red/Blue to the Left When Viewed From Underside of Bracket

Red/Blue to the Left When Viewed From Underside of Bracket

The wires fit tightly into the hole and the edges of the hole are sharp. I don’t want to damage the wires as I pull them out. After some fiddling, I find that holding both wires in one hand and then using my thumb to put pressure on them, I get them to come out gently by wiggling my hand back and forth using my thumb as a fulcrum. I go slow and they finally come out.

Pull Turn Signal Wires by Using Thumb as Fulcrum and Gently Wiggling

Pull Turn Signal Wires by Using Thumb as Fulcrum and Gently Wiggling

After I get the wires out of the old bracket, I push them into the new one. I can push one side all the way through and then the other. I didn’t need to use a pull-wire to get them to threaded through the bracket.

The ends of the turn signal wires go into the bottom of the stop light shell. There is an oval rubber gromet that goes between the bracket and the tail light housing and has a groove to hold it in the housing.

Tail LIght Showing Turn Signal Wires Gromet

Tail LIght Showing Turn Signal Wires Gromet

A round rubber gromet goes into the rear of the tail light housing where the wires inside the left side of the subframe tube go into the tail light housing.

Rear Subframe Wiring Gromet

Rear Subframe Wiring Gromet

I thread each wire through the gromet.

Thread Rear Subframe Wires One By One

Thread Rear Subframe Wires One By One

At this point I check that the correct colored wires for the turn signals are working. I insert the key and hit the turn signal on the right side and verify the turn signal wires coming into the back of the turn signal housing from the subframe wires has power.

Testing Turn Signal Wires Are For Correct Side

Testing Turn Signal Wires Are For Correct Side

The back of the tailight is used for connecting all the wires. I made a diagram of what wires went where when I disassembled it.

Tail Light Wiring Diagram and Tail Light Terminals

Tail Light Wiring Diagram and Tail Light Terminals

The wires frome the subframe go into clips. It is easier to use needle nose pliers to comperss the clip and thread the wire than using my fingers. The clips are strong.

Use Needle Nose Pliers to Pinch Spring Terminal

Use Needle Nose Pliers to Pinch Spring Terminal

Then I slip the spade connectors for the rear turn signals onto the lugs.

Adding Turn Signal Wires to Spades on Turn Signal Wire Terminals

Adding Turn Signal Wires to Spades on Turn Signal Wire Terminals

The tail light reflector has a hood on top and is open at the bottom so the running light shines on the license plate.

Rear Reflector, Cut Out Goes Down,Hood Goes Up

Rear Reflector, Cut Out Goes Down,Hood Goes Up

I attach it with the reflector and the two screws.

The turn signal reflectors have two pinch connectors for the wire end. These are easier to depress using the blade of a large flat blade screw driver. I make sure the wire extends all the way through the hole in the punch down.

Attach Wires to Turn Signal so Wire Passes Through Both Sides of Punch Down

Attach Wires to Turn Signal so Wire Passes Through Both Sides of Punch Down

The turn signal reflector mounts one way in the housing with the “hot” wire (not the brown one) to the outside.

Turn Signal Bulb Housing Goes One Way

Turn Signal Bulb Housing Goes One Way

The turn signal housings mount on the ends of the bracket tubes with pinch bolts.

Pinch Bolts Mount Turn Signal Housing on Stalks of Tail Light Bracket

Pinch Bolts Mount Turn Signal Housing on Stalks of Tail Light Bracket

The tail light housing attaches to the bracket and the bracket attaches to the fender using two bolts. There is a steel washer in between the tail light housing and the bracket.

Washer Under Tail Light Shell and Top of Bracket

Washer Under Tail Light Shell and Top of Bracket

Attach License Plate Bracket and Rear Reflectors

The license plate bracket includes tabs for the rear reflectors. The bracket attaches to the rear fender with three bolts and locking nuts. The three bolts make a triangle with the top bolt being the top apex of the triangle.

License Plate Bracket and Hardware

License Plate Bracket and Hardware

There are three reflectors, two on the side and one on the rear under the license plate bracket. The rear one has a sculpted rubber gasket.

Rear Reflectors-Two Side Reflectors and a Center One with Rubber Gasket

Rear Reflectors-Two Side Reflectors and a Center One with Rubber Gasket

Here is the final tail lights, turn signals, license plate braket and license plate installed.

Tail Light, Turn Signals, License Plate Bracket Assembled

Tail Light, Turn Signals, License Plate Bracket Assembled

Side Reflector Mounted to Tab on  License Plate Bracket

Side Reflector Mounted to Tab on License Plate Bracket

Attach Front Fender

At the bottom, the front fender attaches to a chrome bracket that attaches to the fork tubes and at the top, it attaches to the fork brace.  Here is the front fender hardware. The two carrage bolts at the top go into the chrome bracket.

Front Fender Mounting Hardware

Front Fender Mounting Hardware

The carriage bolt goes through the inside of the chrome bracket. The rubber gasket goes next to the fender with a steel washer and locking nut on top.

Front Fender Lower Mounting Assembly

Front Fender Lower Mounting Assembly

As with the rear fender, the rubber gasket goes against the fender with and under the fork brace bracket with the locking nut on top. The top mount for the front fender does not use a steel plate on the inside of the fender.

Front Fender Top Mounting Assembly to Fork Brace

Front Fender Top Mounting Assembly to Fork Brace

Here is the front of the bike with the front fender installed.

Front View with Front Fender Mounted

Front View with Front Fender Mounted

Attach the Seat

The bike has a custom touring seat from Mustang. It is a vintage 1970-1980 upgrade for touring.

After Market Seat by Mustang

After Market Seat by Mustang

It mounts with the stock hinges and hardware. The hinges are different and only go one way.

Stock Hinges and Hardware-Front Different from Rear

Stock Hinges and Hardware-Front Different from Rear

Stock Hinges Go One Way-Front is Different from Rear

Stock Hinges Go One Way

Mounting the hinges is never easy for me. As shown below, one screw on each hinge is over the frame tube. Therefore, I have to mount the hinges to the seat using that screw run in to snug, but not tight so I can rotate the hinges to get them on the pivot pins in the subframe.

Hinges on Subframe Pins Showing Blocked Screw Holes

Hinges on Subframe Pins Showing Blocked Screw Holes

I have not found an easy way to mount the seat. It is bulky and has a mind of its own. However, I can rotate the hings since they are attached with a single screw and then get them onto the hinge pins. As shown below, the front hinge is being pivoted to get the hole over the pin in the subframe.

Rotaring Hinge on One Snug Screw to Slide it On the Pivot Pin in Subframe

Rotaring Hinge on One Snug Screw to Slide it On the Pivot Pin in Subframe

Once I slide both hinges onto the pins, I attach the remaing two screws for each pin using a long blade philips screw driver from under neath the bike. I can then tighten them after about four or five tries as the screw keeps falling off the srew driver blade.

Tightening Remaining Two Screws From the Bottom

Tightening Rear Hinge Screws From the Bottom

Tightening Front Screw From the Bottom

Tightening Front Hinge Screw From the Bottom

Attach Side Covers

I painted new horizontal stripes on the side covers, not once, but twice. But, when I went to mount them, I still wasn’t happy with the way they came out. So, I painted them a third time. The third time was the charm.

You can see what didn’t work and what did work in this writeup.

Here is the final product.

Third and Final Paint Job on Side Cover

Third and Final Paint Job on Side Cover

The left side cover has a cutout to go around the grab bar. To get it on, I loosen the bolts holding the grab bar and rotate it upward so I can get the cutout around the front of the grab bar. Then I rotate the grab bar back down and tight the bolts.

Here is the bike with the side covers and Mustang seat attached.

Side Covers and Seat Attached

Side Covers and Seat Attached

Add Tool Kit & Tire Pump

This bike never had the original tool kit nor tire pump. So I bought them and a shop rag from Hucky’s. Here is the tool kit, shop rag and the registration and insurance with their protective sleeve.

New Tool Kit and Shop Rag-Registration & Insurance

New Tool Kit and Shop Rag-Registration & Insurance

I cleaned up the original tool box and used some “Forever Black” on it.  This is the first time in seven years the registration and insurance have been on the bike 🙂

Tool Box, Tools and Tire Pump Installed

Tool Box, Tools and Tire Pump Installed

Glossy Pictures of “Grover” Back Together Again

So, I’m done!!!! The bike is finally complete and ready for it’s first ride around the block. I’ll post about the first ride separately.

Here are some “glossy” photos of the final product.

Front Profile

Front Profile

Gas Tank

Gas Tank

Instruments and Steering Damper

Instruments and Steering Damper

Front Wheel Hub Cab

Front Wheel Hub Cab

Left Carburetor

Left Carburetor

Right Carburetor

Right Carburetor

Push Rod Tubes

Push Rod Tubes

Engine Badge

Engine Badge

Sito  Mufflers

Sito Mufflers

Sito Mufflers

Sito Mufflers

Rear

Rear

Reflections in Fairing

Reflections in Fairing

3 thoughts on “00 BMW 1973 R75/5 Final Assembly

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