How do I repair a fairing?

[PlaneGuy]

Shattered glass! That is what my fairing is like. No, I didn't crash. Heck, I have no CLUE why my fairing is like fragile shattered glass. But it is and, quite frankly, I am not one of those who believes that duct tape is a permanent fix. (But it is one hell of a great temporary fix and can even hold airplane fabric together until one can make permanent repairs -- don't ask how I know.)

I went to ride yesterday afternoon. (Bad day, getting out on the road helps.) As I was getting ready my leg brushed the bottom of the lower right side fairing and everything kinda' went SPROING! I don't know why but I suspect excessive heat from the previous owner's special exhaust system. It seems to have turned parts of the fairing brittle.

Cracks I suspect I can deal with using an appropriate solvent-type adhesive followed by a a lay-up of glass or carbon fiber and epoxy. (I would used crossed weave because I am not sure whether I am dealing with tensile or shear stresses and want to carry loads in all directions.) So, I solicit input as to whether this makes sense or not.

What I am more concerned with is rebuilding the attachement ears that are on the upper fairing to which the lower fairing bolts. (Yeah, the upper fairing needs repair too.) That has to be a high stress point and a weak repair will only fail again quickly. That has to be strong. Again, I am looking for suggestions from someone who has dealt with this and found a permanent fix.

Lastly, perhaps the best fix is to find another fairing that hasn't been damaged. I am open to buying one from someone. My 2006 ninjette is black but I am not picky. Function is more important than appearance. And there is always tastefully-applied paint.

So, since I am getting ready to take everything apart in order to do the forks (new springs, new seals, RaceTech cartridge emulator, different fork oil) and adjust the valves, I guess I am going to be making fairing repairs at the same time. Damn. I was hoping to take off and do some serious riding, not sit around gluing my fairing back together.

Help!

[Alex]

One of our members put together a DIY for repairing cracks in a fairing:

http://www.ninjette.org/forums/showthread.php?t=42690

and another here:

http://www.ninjette.org/forums/showthread.php?t=16348

But your fixes might need to be more extensive. Finding cheap plastics as they pop up here and elsewhere might not be a bad way to go either.

/thread moved to pre-gen tech, not about a specific crash.

[PlaneGuy]

Thanks Alex. I appreciate it.

[dale-j]

Sounds like my old FJ1200. Vibration, heat (air cooled bike) and cheap (almost ABS -like) fairing material did that one in, as it never hit the ground but needed extensive (!) work on the tabs and had large stress cracks. I've crashed Hondas with nothing but surface scratches, but Yamaha plastics....

Your approach with solvent based adhesive (or krazy glue) followed by glass and resin is what I did on mine (works best if you thoroughly roughen and clean with solvent in behind first), and I found that the ears could be rebuilt with a two part epoxy putty (purchased here in BC at a place called Industrial Plastics) to form the tabs. I then machined them to shape with a die grinder and added a bit of resin/glass reinforcement. It was a lot of work, but as all the pieces lined up perfectly and had no paint damage the end result was fantastic - couldn't see the cracks, paint all lined up, and hey they only weighed about five pounds more (ugh)....

Some of the fittings needed to be changed from the original style so I riveted and glassed in Dzus quarter turn fasteners. I'm sure you can adapt whatever you like to use if you need to BUT....

On that note, new fairings might be a better option and certainly less time intensive.

Steve

[PlaneGuy]

Well, considering the amount of work that will be required, I pretty much resigned myself to getting a replacement ... until I got the price:

$600 for the upper fairing and $400 for the lower!

So, I am looking to repair or buy used. The tabs were the thing I worried about most. I have worked with structural reinforcing material for epoxy for making structural fillets. (I used to live on a 48' wood, glass, and epoxy sailboat so I became fairly adept at using that.) It is good to know that someone has done this before and has charted the waters.

I like the idea of Dzus fasteners or camlocks but I can live with bolts.

Thanks. I'll go hit up my local plastics supply shop for some materials and advice.

[CZroe]

http://www.murphskits.com/catalog/pr...roducts_id=465
Sheets of ABS plastic whic can be formed somewhat with careful use of heat.

http://www.murphskits.com/catalog/pr...roducts_id=247
PlastiFix but you can probably use regualr ABS Cement just the same.

[JLinde1339]

Easy fix:

1) Remove fairings

2) Toss fairings in a corner/trash bin

3) Ride nekkid!!!!
Posted via Mobile Device

[PlaneGuy]

I am considering the efficacy of running without fairings. Certainly easier when it comes to doing maintenance. Still, it looks better with the fairings and I suspect that the fairings provide better cooling airflow through the radiator and across the exposed metal of the engine.

[JLinde1339]

In my experience, I've noticed she runs a lot cooler without the fairings. My temp gauge used to be at about 12 o'clock while at highway speed. Now it runs at about 10 o'clock, or just above the "warm up" zone. I even cut some expanded steel to replace the chicken wire screen that kawi uses to protect the radiator, thinking that may cause more restriction, but still runs cooler.
Posted via Mobile Device

[Jiggles]

Originally Posted by PlaneGuy

I am considering the efficacy of running without fairings. Certainly easier when it comes to doing maintenance. Still, it looks better with the fairings and I suspect that the fairings provide better cooling airflow through the radiator and across the exposed metal of the engine.

I think they look good naked!

[coolbreeze]

Naked sounds good, fairings look great IMO. I would have an issue with possible exposed wires/hardware. Now, to answer your question, I have helped repair plastics on 2 bikes, and they are still holding up. One is a 675 (damaged front fender, fairings in blinker area). The other is 750 (tail section, fairings on both sides, and front fender). I'll actually be doing the underside of my front fairings sometimes this winter. I can't remember the product's name, but it is sometype of plastic/abs fix from autozone.

[n4mwd]

Ninjas and some people should not be allowed to go around naked.



Its best to repair or get some new fairings. Otherwise people will stare.

[Apocolypze01]

If just cracks. Follow these steps and it will be stronger than the original

Sand the underside of the fairing at the location of the crack about 5 cm from the crack in every direction with some 80grit sand paper.

Clean the sanded area with some rub in alcohol or similar chemical.

Using a soldering iron, make a groove in the location of the crack on both the inside and outside of the fairing.

This is with the sandpapered area and a groove cut in



On the inside, use a fiberglass kit with fiberglass blankets. The rough surface created by the sandpaper will help the resin of the fiberglass bond better.

This is the fiberglass on the inside:



On the outside, clean it with alcohol. Sand it back with 80grit again.

Then mix up a auto body-filler. Apply that. Sand it down. And bobs your uncle. Good as new!

Here are some before and afters:

Before:



After (the grey areas are the parts where cracks were repaired):

[onetruevibe]

The PO of my bike did a number on the fairings, so stripped them down, fixed the cracks and repainted for under $30 cash money.

It was a good learning experience and they turned out fine, but a real PITA.

You can read more here

[n4mwd]

I really don't think its a good idea to use auto body filler (aka Bondo) on ABS plastic. The problem is that most body fillers are polyester based resins. These have two issues that make them unsuitable for bikes.

The first is that they shrink over time. So all that work will turn into an ugly crack in a few months to a year. This is also true when they are used on cars to fill dents.

The second problem is that polyester resin hardens very stiff. So its like a sheet of glass and prone to breaking. This isn't so bad when fixing a dent on a metal car door, but its just not a suitable match for ABS plastic which is designed to be somewhat flexible.

The preferred filler for ABS plastics like on a Ninja is an ABS based filler. In a pinch, you can also use epoxy based fillers such as JB-Weld, JB-Kwik.

You can usually tell the difference by the way you mix it. Polyester resins use mostly resin and a few drops of hardener. Epoxy resins are mostly mixed half and half. ABS uses a solvent which dissolves the filler material and then dries.