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Somebody1010
03-20-2007, 10:45 AM
http://www.sportrider.com/tech/146_9510_hand/


Fixing Your Fractured Fairings
By Jason Black

1. If you own a faired motorcycle, chances are you've had the near-heart attack experience of pricing replacement bodywork. Whether you've simply dropped Your Precious off its sidestand or performed a full-on face skid, the dollar signs can quickly soar into the quadruple digits. But don't fret; there's hope yet. Put away the JB Weld, duct tape and plastic repair kit-there's an easier and more sano way.
http://sportrider.com/tech/146-9510-HAND-1K-zoom.jpg
http://sportrider.com/tech/146-9510-HAND-2AK-zoom.jpg
http://sportrider.com/tech/146-9510-HAND-2BK-zoom
We had a partially damaged Body by Northstar tailsection that we put to the asphalt test at Daytona. The bodywork held up exceptionally well considering the severity of the crash, but still had a sizable hole and crack in the side. Note that this repair was done on a fiberglass section, but we have done the same procedure repeatedly with stock ABS fairings.

2. Begin by cleaning up the damaged area. Wipe it down with contact cleaner or acetone, first making sure that it will not damage the bodywork. Next, use 280-grit sandpaper to completely roughen the surface around the damage, both on the interior and exterior. If you have a grinder-bit attachment for a drill, this works extremely well. Failure to create a scored surface will keep the fiberglass material from bonding correctly.

3. Next comes the messy part, which can be potentially brain-damaging and/or hallucinogenic if you're not wearing a respirator. First, clean the area again. Then, cut out pieces of fiberglass mat or cloth (mat is slightly stronger but cloth is easier to work with) in the shape desired. Then mix the fiberglass resin with the catalyst as per the instructions on the box. One or two ounces is all that is needed for most repairs. Fiberglass repair kits are available at most auto parts stores, and make sure you pick up some latex surgical gloves at the same time-this stuff is sticky.
http://sportrider.com/tech/146-9510-HAND-3K-zoom.jpg
http://sportrider.com/tech/146-9510-HAND-4AK-zoom.jpg
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http://sportrider.com/tech/146-9510-HAND-4CK-zoom.jpg
Once the resin and catalyst have joined forces, you'll only have 20-25 minutes to work with the mixture before it begins to solidify. Use a paint brush and apply a thin layer of resin all around the interior damaged area.

4. Now take the pieces of fiberglass cloth and carefully place them in the desired area. Situate the cloth so it best resembles the original shape of the fairing; the better it looks now, the easier it will be to complete the project later. Work the resin up through the cloth with the brush in order to keep the fiberglass in place. Continue to dab on resin until the region is completely wet-but not saturated-and there are no visible wrinkles or bubbles. Remember that it's crucial to fiberglass the outside of any cracks to ensure there's no breakage later.

5. After the first layer has dried sufficiently, repeat the process, layering on more fiberglass while making sure not to exceed the original thickness of the fairing.

When the last application of cloth has dried entirely, use the grinder or 80-grit sandpaper to carefully knock down the excess fiberglass and resin-just make sure you don't grind all the way into the cloth, as that would weaken the structural integrity of the hardened fiberglass. Finally, scuff the entire area once again with 280-grit and clean it with acetone.
http://sportrider.com/tech/146-9510-HAND-5K-zoom.jpg
6. The final step of the repair process involves making everything look right using polyester body filler (Bondo). Patience is the key when working with body filler. Do it right and nobody will know; do it wrong and your bike won't even pass the 50/50 beauty contest: 50 feet, 50 mph. If the area you're repairing is more than a few square inches, drill several very small holes in the fiberglass so the filler can squeeze through and secure itself to the fairing, similar to the function of finger holes in a bowling ball.
http://sportrider.com/tech/146-9510-HAND-6K-zoom.jpg
7. Mix the filler and hardener according to the instructions on the can. Using a thin, rubber-spreading card, begin applying thin "skim" coats over the fiberglass, making sure that some filler squeezes through the holes on the first coat. Feather the mixture onto the surrounding painted surface; the idea is to blend the filler onto the existing fairing without creating a rough edge, and to make the filler best resemble the origi-nal shape of the fairing. Oh, and by the way, you best hurry up-polyester filler is unspreadable after two minutes.

8. Once the mixture has reached the consistency of your average block of Monterey Jack, start whittling it down with 80-grit sandpaper. Allow each application of filler to dry completely between coats, repeating the process until it is layered and sculpted to resemble the original fairing. For the final application, disperse a smooth layer of filler over the entire vicinity and let it dry. Sand it with 280-grit and then wet-sand it with 400-grit wet/dry sandpaper until you can no longer feel any scratches or imperfections in the plastic or filler.
http://sportrider.com/tech/146-9510-HAND-7AK-zoom.jpg
http://sportrider.com/tech/146-9510-HAND-7BK-zoom.jpg
http://sportrider.com/tech/146-9510-HAND-8K-zoom.jpg
9. Just to demonstrate how good the final product looks, we shot on some white primer paint. When done properly, these methods are structurally sound and extremely effective. In fact, on the way home after our photo shoot, the tailsection fell out of the back of the SR Toyota T100 and landed right on the repaired area at 40 mph. There was no damage other than a few scratches.
http://sportrider.com/tech/146-9510-HAND-9AK-zoom.jpg
http://sportrider.com/tech/146-9510-HAND-9BK-zoom.jpg
http://sportrider.com/tech/146-9510-HAND-SBK-zoom.jpg
So next time you find yourself staring at a cracked and splintered fairing, break out the fiberglass and body filler and give it a try. With a little patience, you'll have a good-looking fairing and a thicker wallet.

How and why

Our partially destroyed guinea pig bodywork was volunteered by Body by Northstar (612/252-2924). All other supplies were acquired at a local auto parts store for the grand sum of $15. Not bad when compared with the cost of a new fairing. To prep your repair job for painting, see "Hands On," August '94. To complete a fairing rebuild, you will need the following supplies:

80-, 280- and 400-grit sandpaper
Acetone or contact cleaner
Latex surgical gloves
Spreading cards
Fiberglass cloth, resin and hardener (all available in a fiberglass body repair kit)
Polyester body filler (Bondo)
Scissors
Mixing sticks
Respirator (optional but strongly recommended)



This article originally appeared in the October 1995 issue of Sport Rider.

BigComfy
03-20-2007, 10:47 AM
sticky please

Somebody1010
03-20-2007, 10:58 AM
figured i would add something with some value to MH

jrock
03-21-2007, 08:37 PM
good post!!
Needed it about a month ago but good find indeed.

Scorpio
03-21-2007, 09:09 PM
yes,
the mini will be needing a whole lotta that stuff pretty soon at the rate we're going.
good info.

xtnomad
03-21-2007, 09:30 PM
There are a few differant tricks pepole use but mostly the same results. This is text book. Gelcoat works best with microspheres in the mix, it can cover up 24g scratchs. This reminds me of my boat yard days that I was covered with glass every day. And the 3 x 100 foot rolls of cloth in the garage, any offers? I think I starting to itch. :eek3:

houseofpaint
03-22-2007, 01:55 AM
depends on the plastic.......all plastics have a code of some sort if you look on the back of the plastic.....

i typically plastic weld, but there is like 8 different kinds of plastics, some cannot be plastic welded. there are many different adhesives and fillers for different types of plastics, using the wrong one for the wrong plastic, most likely will not hold long.

THE DEAN OF LEAN
09-08-2008, 08:43 PM
depends on the plastic.......all plastics have a code of some sort if you look on the back of the plastic.....

i typically plastic weld, but there is like 8 different kinds of plastics, some cannot be plastic welded. there are many different adhesives and fillers for different types of plastics, using the wrong one for the wrong plastic, most likely will not hold long.

where is the code at? and what will it say! better yet, I think I have gp bodywork, know whats best for me to use?

Somebody1010
09-08-2008, 08:46 PM
Im pretty sure your stuff is fiberglass so go with the meathod above. Take your time on it though to get it smooth and looking good again.

Heytalktoryan
09-25-2008, 11:23 AM
Good lord i help this shit can help me fix my bicycle.

1slocbr
01-12-2009, 08:39 PM
i use this stuff called problem plastic repair. if you lay it down good you can prime right over it without usin mudd.

TRD23
02-10-2009, 05:10 PM
yeah ive been using plastix repair. works like a charm. probably do the fiberglass for major repairs

texlurch
05-04-2011, 04:05 AM
Plastic welders can be had for $40 or so. i found mine on Ebay, and it included 3 types of plastic rods.

Plastic fairings will have the type in raised letters on the back side, usually ABS or PVC.

To begin, choose the proper rod.
Degrease the area on both sides, brakecleaner or wax/grease remover works
sand down the paint in an area about 3 inches to either side of the crack
form a V shaped bevel in the crack, on both sides of the fairing
if the crack only goes part way, drill a small hole at the end to reduce chances it will reappear
You can use a triangular file or dremel attachment
hook up your welder (mine uses 120VAC and compressed air
Start at the end where you drilled the hole, use the tip of the welder in a circular motion to heat the fairing
When you start to see signs of melting, start feeding in the filler rod
I find it works better to push the rod rather than drag, using a dipping motion and proceed to the end of the crack
Flip the fairing over and repeat
Sand down the repaired area and complete bodywork as above

Track_Graphics
05-11-2011, 10:00 AM
Quick comment -
Don't use reducer to clean ABS. It will "melt" the plastic and make it glass smooth and any fiberglass will pop off like potato chips. Also, fiberglass continues to cure for years. If you make it too thick it can develop cracks within itself because it continues to shrink.
If you need some repair work you can give me a try. www.TrackGraphics.us

OpnCskt
10-26-2011, 12:02 AM
Can you fix this bodywork?:shrug::shrug::shrug:

MGZT
11-30-2011, 09:30 AM
I wanna add to this.. Do not use pain stripper on Fiberglass fairings because it will mess up the gel coat on it