Moto Guzzi 80's era fairing plastic.

[sdcr]

  My fairing on the Le Mans III is constructed of some type of plastic. it may  be ABS, or something similar. I noticed a stress crack along the bottom, near the center mounting hole.

  I want to use an adhesive to repair it, and would like to hear from some other who found a product that works well on this type of material. 

   I have tried JB weld, which usually fixes anything, but it did not adhere to the surface area, once it cured.

Any suggestions n a specific product?

[Groover]

I would use epoxy, but combined with fiberglass cloth. Basically brush epoxy, then a layer the fiberglass cloth, repeat until you have a nice sturdy looking repair.

Fiberglass cloth can be found at hobby stores (R/C hobby, not crafts) and comes in different strengths usually the coarser the weave, the higher the rating. The fiberglass cloth will "melt" into the epoxy. Once all is dried, sand it until you're happy with the results.

Good luck.

[pehayes]

Yes, it is likely ABS.  Vetter used to sell a "hotcha" kit for repair to their ABS fairings.  You can get ABS glue and small bits of sheet plastic for repairs at a good hardware store or plastic supply like TAP.

Patrick Hayes
Fremont CA

[rboe]

My Quota had black plastic tupperware and most bits had cracks. Thinking it was ABS I used ABS cement for plumbing pipe that I had laying around. This worked on the side cases but not on the front fairing. Different plastic. That was an eye opener!

By the way, the ABS glue worked great and I reused it recently on an OLD Pacifico top case that fell into my hands.

[Matt Story]

If ABS, I have learned the following from printing 3D models in ABS.  Acetone used in very small amounts will marginally melt adjacent surfaces (like a crack)  and result in a surface bond.  You might brush it on the crack from the inside of the fairing with a model brush.  I mean a very small volume.  Capillary action will draw it into the crack and create the bond.  Hold it for a few minutes.  My understanding is that the acetone melts the 2 halves so they can bond, and then evaporates.  You might want to follow up with a lap of fiberglass or epoxy on the inside for reinforcement.  May be worth trying.  Please try first in a small inconspicuous place.

Matt

[swooshdave]

If ABS, I have learned the following from printing 3D models in ABS.  Acetone used in very small amounts will marginally melt adjacent surfaces (like a crack)  and result in a surface bond.  You might brush it on the crack from the inside of the fairing with a model brush.  I mean a very small volume.  Capillary action will draw it into the crack and create the bond.  Hold it for a few minutes.  My understanding is that the acetone melts the 2 halves so they can bond, and then evaporates.  You might want to follow up with a lap of fiberglass or epoxy on the inside for reinforcement.  May be worth trying.  Please try first in a small inconspicuous place.

Matt

I don't think you'll need to reinforce at all. You may find the bond from the acetone stronger than the surrounding ABS.

[bigbikerrick]

Polyvance is the company that  I have found has the best products for professional plastic repair. I have been using their products for many years. their "flex filler" is what you want to use. It is a 2 part epoxy. It will stick tomost anything that is properly prepped. Its great stuff.
http://www.polyvance.com/Flex-Filler-1/2000-T/
Rick

[Matt Story]

Another glue I have used on printed ABS parts is PVC/ABS pipe cement.  Beware that this is much more aggressive in its melt capability.

[sdcr]

If ABS, I have learned the following from printing 3D models in ABS.  Acetone used in very small amounts will marginally melt adjacent surfaces (like a crack)  and result in a surface bond.  You might brush it on the crack from the inside of the fairing with a model brush.  I mean a very small volume.  Capillary action will draw it into the crack and create the bond.  Hold it for a few minutes.  My understanding is that the acetone melts the 2 halves so they can bond, and then evaporates.  You might want to follow up with a lap of fiberglass or epoxy on the inside for reinforcement.  May be worth trying.  Please try first in a small inconspicuous place.

Matt

H
 Matt,
This sounds like a worthwhile try. One of my riding buds also suggest trying something called Q-Bond. It's a two part epoxy that contains reinforcing powders.
Thanks to all for the good suggestions.