Plastic repair or sources for new.

[timgray]

My Venture is starting to crack a LOT. many of the cracks I repaired when I repainted the bike are reappearing, mounting tabs breaking off again, etc.. Anyone have a clue as to how to stop this? I have tried all the recommended repair techniques and all of them fail after a year or two. the ONLY repair that is still intact is where I added an 1/8 thick piece of ABS to the back of the panel.

 

I am back to having to repair or re-repair cracks every spring in hopes of making it through the summer.

 

If I can't stop all this cracking, it may be time to give up on the old girl and sell her for parts.

[saddlebum]

Half my bike was rebuilt with plastex or plastifix (same product just a different name depending on who you get it from). After my accident in 2007 I rebuilt it using the above products. The left fairing is actually two half sections welded together with plastex/plastifix.

Drill a 1/8 inch hole at the end of the cracks, then gouge/V-out the crack from the back side cover the crack from the outside with clear packaging tape, then fill the crack from the inside. Sprinkle on the powder then wet with the liquid and alternately add powder and luiquid until the crack is filled. Next cover the repair on the inside with fiberglass drywall tape. Then sprinkle just enough powder over the tape to sift through the holes of the tape and wet with liquid then add more powder and liquid until the drywall tape is completely covered (mixing proportions are not important, you can make it as runny or stiff as you like depending on the circumstance).

Once curried about 15 to 20 minutes you can peel of the tape on the outside. If there are any little imperfections on the outside just add a bit of plastex using the dropper technique with the included dropper (instructions are included in the kit).

Plastex/Plastifix builds up as required and can be built up in layers, sands out glass smooth and there is no need to use any spot putty.

You can even smooth it out with you finger when it starts to firm up a bit to putty like consistency. ( works best if you fold a piece of clear packing tape over you finger, it wil not stick or build up on the clear tape but it will on a bare finger.

 

A couple of source links for the products

http://venturerider.org/forum/showthread.php?t=74332

 

After repairing and painting bike.

 

http://venturerider.org/forum/attachment.php?attachmentid=22720&stc=1&thumb=1&d=1223431960

Edited May 5, 2013 by saddlebum

[timgray]

I tried the plastex stuff, and that is also cracking. they have not cracked enough to reach where I drilled the hole, but I can see it starting again.

 

My biggest problem is every single mounting tab I repaired has failed exactly the same way the original has. Anyone have tricks to make the mounting tabs stronger? some of the tabs I replaced using the Plastex method, and those have failed as well. They stayed attached to the fairing, but a new crack has appeared shearing it off, or the plastex it's self splits.

[Marcarl]

I tried the plastex stuff, and that is also cracking. they have not cracked enough to reach where I drilled the hole, but I can see it starting again.

 

My biggest problem is every single mounting tab I repaired has failed exactly the same way the original has. Anyone have tricks to make the mounting tabs stronger? some of the tabs I replaced using the Plastex method, and those have failed as well. They stayed attached to the fairing, but a new crack has appeared shearing it off, or the plastex it's self splits.

Maybe one ot the steps you missed is that Plastifix will not adhere to paint, so the paint has to be removed, also from the back side. The other step is to make sure in the situation of a tab, that you build up the inside corners as best as possible. I have fixed a number of tabs and cracks, and the only one I had problems with were the ones where I didn't remove the pan first. And everything has to be CLEAN!

[Snaggletooth]

I've done every damaged mounting tab or crack with two part epoxy and laminating it with thin sheets of ABS plastic I got from advertising signs from a grocery store. Same material and if needed it can be shaped to a curve with a heat gun.

 

I'd cut a piece to shape, rough sand the surface and wipe it down with alcohol to prep it. Treat both sides with epoxy and clamp them together.

 

When it cured I'd shape and drill to fit. It the repair was a bit too thick I'd sand the new sheet down a bit. The repairs I did several years ago are still intact. I broke one tab on the side cover during the cold winter weather but I had leaned against it with my knee. Had that one coming. Re-did the repair and it's holding up fine.

 

There are very few spots where the fixes are seen without looking for them. The way the panels overlap they hide pretty well.

[timgray]

I have not tried this! Thanks!!

 

Off to get some sign material and try this route.

[Snaggletooth]

If I'd known I would have sent some sheets along with the pump parts.

 

Most providers use the ABS panels on their racks and displays. Shouldn't be too hard to find an old display being tossed.

[Prairiehammer]

Another source for ABS: most plastic computer cases. I've used cut up cases for repairs utilizing ABS cement (it is black and the repair, done properly, is stronger than stock.) MEK solvent is your friend. In fact, for some repairs I've used MEK alone to glue ABS parts together.

Downside: not as many black parts on old computers.

[camos]

MEK solvent is your friend. In fact, for some repairs I've used MEK alone to glue ABS parts together.

I like MEK too because it is inexpensive and adaptable to various repair situations. As a source I've been using left over bits from plumbing pipe repairs. Mix MEK and some cut up bits in a small seal-able Mason jam jar and overnight it will have dissolved into a paste or a slurry depending on how much MEK was added. MEK is very volatile and evaporates almost instantly.

 

A hypodermic needle is the best way to inject it into a crack. With a broken off tab, lay some on each side of the joint and hold together for 30-40 seconds and it will be bonded. Use the paste to spread on the back side to build up a reinforcement. It can be molded and shaped using just your fingers by scooping out a suitable amount and letting it dry until it has the consistency of clay. That takes maybe 5 minutes depending on what you are starting with. I used that method to repair the left dash attachment points just above the speakers where the outside edges had broken away and were gone. Once it set for a bit the plastic can be cut and shaped with a knife and then drilled. With the screws in the attachment points look as good as the original.

 

On the VR I made a couple of repairs using this method in June of last year. Been on a couple of trips, to Nelson and Kelowna and was my daily rider until Nov when the VR went into the barn for maintenance.

 

Also use some MEK mix to fix the bottom attachment point on the windshield of the Virago which had cracked right through the bolt hole. Had tried repairs using various other methods but they all failed after 2 or 3 weeks. There is quite a lot of movement of the windshield when riding but the MEK fix is getting into 7 months now of daily riding.

 

Anyway, this MEK repair method seems to be simple, reliable and economical.

And, no I don't have shares in MEK suppliers.

[jilldwr]

I had posted this link a few years ago:

http://www.venturerider.org/forum/showthread.php?t=65701&highlight=jilldwr

 

Since then (last spring), I found several major cracks on the floor of my 1999 RSV trunk - a known weak spot. I followed the advice in this video and welded the bottom back together with zip ties and copper wire for support. It has worked very well for me. No signs of weakening and the paint has no cracks either. I bought a soldering iron used for stained glass making, about 35 watts I believe , and it did quick work of the welding. I placed copper wire on the weak spots and pressed the soldering iron on the wire and watched it dissappear into the plastic.

In November of 2011, I had a large split crack in my lower left fairing. I applied the same process of imbedding a copper wire and building up with melted zip ties. I them sanded and repainted with base coat, clear coat. It looks brand new and has not cracked in the same place again.

Hope this helps...