HOWTO: fix the broken tabs on your rear plastics

[jiggersplat]

They say there are two kinds of GS500 riders.  Those who have broken their mounting tabs off their rear plastics, and those who haven't yet.  Here's how to fix it using ABS plastic.  The reason I prefer this method over adhesives/epoxy is that you actually get a good molecular bond, similar to welding metal.  The acetone dissolves the plastic.  When the acetone evaporates you have in effect, a single piece instead of two pieces glued together.  Furthermore, ABS plastic is flexible, not brittle like the bond you would get with something like superglue so you're less likely to break it again.

What you need:

• acetone
• abs plastic pellets
• latex gloves (not nitrile rubber!)
• mixing paddles
• mixing container
• about an 45 minutes

Before you start, you'll want to do this in an extremely well ventilated area (like outside) and if you've got a respirator, you might want to go ahead an use it.  Also, be careful not to get acetone on any visible painted surfaces.

Prep your plastic parts by removing any debris and wiping down the areas that are going to be bonded together with a paper towel dipped in acetone.  This will help remove some paint and help get a better bond.

Before you go any further, get a good feel of how the tab mates with the fairing it broke off of.  Hopefully you have a nice clean break and the pieces fit back together snuggly.  You'll want to be able to fit these back together later by feel since it will be covered in ABS sludge and you won't be able to see where the parts mate.

Put on your latex gloves and mix equal parts of ABS plastic pellets and acetone.  About one ounce of each ought to do the trick (about a shot-glass worth for you drunks).  Make sure you mix them in a non-reactive container.  A glass baby food jar is a good choice, or you can get empty 1-quart paint cans from Home Deport.  I wouldn't recommend plastic cups as the acetone may dissolve the cup.  The acetone will start to dissolve the plastic pellets.



Stir this with a mixing paddle (I used a popsicle stick) every few minutes to break up the clumps and to keep it form forming a skin on the top.  As the plastic dissolves and the acetone starts to evaporate, your concoction should turn into a stinky, gooey, awful smelling, black mess.  It took about 15-20 minutes for mine to get to the consistency I wanted.



All of the plastic pellets may or may not dissolve.  That's okay.  Once the goo gets to a relatively thick consistency, you're ready to bond the pieces back together.  Wipe the contact area of the tab and the fairing with acetone again.  Then take the tab and apply some of the ABS sludge to the mating surface, and press it back into place.  If your ABS sludge is thick and sticky enough, it should be enough to hold the tab in place.



Hold it in position for a few minutes.  Then go ahead and glob on as much of the ABS sludge as you like around the base of the tab, just remember that you have to bolt it back onto the bike eventually and you don't want to get in the way of any bolts or brackets.  The plastic should start forming a skin pretty quickly, but give it at least 24 hours to set up completely. Mine took a little bit longer.  It will depends on how much you put on and how much of the acetone already evaporated before you applied it.

Once it's fully cured, you should have a good strong bond and can mount it back on your bike.

Lastly, if anyone wants some ABS pellets, I ordered a 10lbs bag and have approximately 9.99lbs left.  I can mail you enough to do your repairs for a postage plus a buck or two.

[The Buddha]

Neat ... doesn't acetone eat the paint.
The "professional" way - clean the crack with a soldering iron, and blow abs rod into it with a plastic welder - hot air basically, blown out of a hose the size of a fuel fitting.
Cool.
Buddha.

[08GSSteve]

3 types of rider  

1.   Those who have broken their mounting tabs off their rear plastics.
2.   Those who haven't yet.
3.   And those who hate plastic for that reason and went NAKED  

Cool simple fix for those who do not own a plastic welder

[dohabee]

awesome, i think i'll give it a shot. I dont have any pellets but maybe I can melt a happy meal toy or something instead.

[beRto]

Good post! Thanks for the write-up!