Author Topic: K6 Side Cover Crack  (Read 498 times)

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Offline jchilper

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K6 Side Cover Crack
« on: May 15, 2021, 07:06:45 AM »
I've read up on how to fix side cover cracks but this one is proving to be "challenging". I can't get the crack edges to line up. It's as if heat was applied and turned the portion that covers part of the airbox out. I've attached images to show this. Has anyone else ever encountered something like this? Would applying heat to the ABS get the cover flexible enough to mate the crack edges? I've read about dipping ABS in boiling water to get it flexible enough to bend. Before I hi-jack my wife's crab pot to try this does anyone have a better idea/method?
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Offline Kenzo1979

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Re: K6 Side Cover Crack
« Reply #1 on: May 15, 2021, 07:12:04 AM »
If you’re prepared to Touch it up after the repairs made, you could drill two small holes on each side and put some strength member like a piece of wood or metal behind it and screw to it to hold it together. I just did a repair job with fiberglass resin and it worked great. But I also had to sand and touchup with primer and paint.


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Offline jchilper

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Re: K6 Side Cover Crack
« Reply #2 on: May 15, 2021, 10:08:41 AM »
I'm really looking for a solution that I won't have to prime/paint. I have the paint for a minor touch up but what's frustrating me is I can't even force the crack closed.
John H. #331
74 CB550
75 CB400F
76 CB750K6

Offline pjlogue

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Re: K6 Side Cover Crack
« Reply #3 on: May 15, 2021, 02:24:35 PM »
Not sure if this is possible given the curves involved.  Can you try and have a backing of a small piece of wood and use a small C clamp to bring the edge back into alignment and then tack it with Cyanoacrylate glue, being careful not to have the glue touch the wood.  Using the thinner CA glue will wick into the crack. 

I did this on my '76 side cover.  Not perfect but unless you get up close you can't tell it was repaired.  I used baking soda and CA glue to build up the back a bit to reinforce the repair. 

If you go this route be sure to have the painted side facing up so the CA glue doesn't dribble out and over the paint.  Use the smallest tip you can get on the CA glue bottle so you can do pinpoint application to the crack.

-P.

Offline HondaMan

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Re: K6 Side Cover Crack
« Reply #4 on: May 15, 2021, 08:32:52 PM »
The plastic (really a resin) that was used for these side covers (after the 1972 model bikes) was once in a while not fully mixed before being injected into the molds. This sort of damage is appearing now just from age: 50 years of something pressing, even gently, against them makes them separate. The body-shop guys around here to fix these up told me once that what needs to happen is: sand (deeply) the back side of the cover so you can lay a bit of the mesh used for repairing rusted-out spots in cars, then squeegee-in some body filler until the whole area is thicker than needed. Then file/sand/shape to the desired appearance, prime and paint. That lasts a good long while. I have done a couple like that and never seen them again (many years ago), so I think they have something going there?
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