BMW Fairing Plastic Repair with Plast-Aid

My R1150-RS had a minor tip over, but it broke the upper fairing and also cracked one of the tabs that the left, front turn signal screws into. 🙁

Cracked Upper Fairing

Cracked Upper Fairing

Broken Tab for Turn Signal Mounting Screw

Broken Tab for Turn Signal Mounting Screw

I used Plast-aid to attach the wiring bulk head connector in a Windjammer II fairing with great success. Vetter used ABS plastic in the Windjammer fairings. I believe BMW is using ABS or a similar plastic for the body work, so Plast-aid will work well with it. It worked so well on the R1150-RS repair that a few months later, I used it to repair a number of cracks in BMW touring cases (aka, Krauser panniers).

Repairing Broken Screw Tab

I use a washer to help reinforce the srcew tab. Plast-aid will mechanically bond to steel, particularly if it has been roughed up with 100 grit wet/dry paper.

Tab Piece, Washer for Reinforcement and Mounting Screw

Tab Piece, Washer for Reinforcement and Mounting Screw

I mix up a small amount of Plast-aid. It changes consistency as the chemical reaction progresses. I wait a minute or two until it is the consistency of pancake batter. While I wait, I put some of the liquid component on the edge of the tab and the remaining edge on the fairing to promote good adhesion. When the Plast-aid has stiffened a bit, I put some on the edge of the broken tab. I hold it against the remaining tab surface of the fairing until it stays put, about 2 more minutes. I use the rest of the Plast-aid, smear some on the washer and the apply it to the back side of the tab for reinforcement. I hold this in place for another couple of minutes and I’m done.

Reinforcing Washer Glued On

Reinforcing Washer Glued On

Repairing Cracked Fairing

The fairing crack repair needs reinforcement. I use a small piece of fiber glass mat and shape it to fit behind the crack. There is a small brace above the crack that reinforces the other screw hole for the turn signal and I anchor the fiber glass against it and down across the crack.

Fiberglass Cut to Size For Reinforcement

Fiberglass Cut to Size For Reinforcement

I mix up a larger amount of Plast-aid and apply some of the liquid component along the edge of the crack to improve adhesion . I put some on the edge of the crack, aline the edges so they are tight and put some masking tape over the crack to hold the pieces together.

Masking Tape to Hold Edges Together

Masking Tape to Hold Edges Together

I put the fiber glass into the Plast-aid when it is the consistency of Elmer’s Glue to soak some into the openings of the fiber glass. I put it on the back side of the fairing, and add some more Plast-aid using a Popsicle stick. I have to hold the patch in place for a minute or so using a finger and the Popsicle stick. When it becomes very firm and the fiber glass stays put, I’m all done.

Plast-aid Soaked Fiberglass On the Back Side of Crack

Plast-aid Soaked Fiberglass On the Back Side of Crack

Here is the final repair. It will need to be sanded, some bondo used to fill in the scratches and painted. But that’s a job for another day when I setup my temporary paint booth again.

Final Repair-Just Needs Painting

Final Repair-Just Needs Painting

6 thoughts on “BMW Fairing Plastic Repair with Plast-Aid

    • Steve,

      That’s the idea. As the old saying goes, “It’s easy when you know how.” 🙂

      Good Wrenching.

      Best.
      Brook.

  1. Nice, I recognize the wall fiberglass tape 🙂 I have an 87 RS fairing going on an 84 rt to rs conversion, and the engine cover is straight plastic and very flexible. I am going to change it to an older SMC cover but I need to rebuild the two tabs, as they are missing. I am going to try Fiberglass cloth sandwiched with UPOL Light (recommended ) as is short strand fiberglass to hold it. Any other ideas? BTW new paint 2K Car-Rep looks promising.

    • BTW when you painted the fairing did you paint each individual part, and then assemble? I’ve seen people assemble it and painted assembled as well. I’m always worried about the seams in this manner…

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