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Has anyone seen this problem?
[url=https://app.photobucket.com/u/everettmclendon/a/a8b5b03b-ad65-49a1-a3d0-f45df1fc2c20/p/a65ed968-06ce-4f37-bfa5-6554b0a8172c]
It is melted on the inside. Is dished in some on the outside with cracks radiating out from the dished melted area you can see and feel with a fingernail.
My guess is when parked in the sun, light was reflected from the reflector and melted it. Other theories are welcome.
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(05-23-2021, 12:21 AM)Lord Popgun_imp Wrote: Has anyone seen this problem?
[url=https://app.photobucket.com/u/everettmclendon/a/a8b5b03b-ad65-49a1-a3d0-f45df1fc2c20/p/a65ed968-06ce-4f37-bfa5-6554b0a8172c]![[Image: e327cdcf41e5405c121c2d488b7cbfd6.HEIC]](https://cb1100forum.net/forum/uploads/imp/202105/e327cdcf41e5405c121c2d488b7cbfd6.HEIC)
It is melted on the inside. Is dished in some on the outside with cracks radiating out from the dished melted area you can see and feel with a fingernail.
My guess is when parked in the sun, light was reflected from the reflector and melted it. Other theories are welcome.
The sun reflector idea makes sense to me. Ive used solar ovens when backpacking. They get HOT
2014 CB1100, 1981 KZ440 LTD, 1993 Yamaha XJ600 Seca, 1994 Yamaha XJ600 Seca
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I've seen this happen on the outside lens when a bike is left idling for a long time and a jacket or cover is draped over the light. Could also be sun reflection, since sportbike windshields have been known to melt gauges.
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I'll buy into the sun concentrator theory.
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Figuring that if it happened once it can happen again i took a transparent piece of paper ( a receipt in this case ) held it over the top part of the headlight and with a torch held at the same angle the sun would illuminate the headlight and aiming at the bottom half of the headlight i could produce a blob in the area that the spot is shown.
Initially i entertained the theory that the co2 content was higher in the headlamp

but i just could not prove that so i'll stick with Lord Popgun's et all findings

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On my 2007 R1200R, I put some clear cling vinyl over the lens to prevent stone chips. Within a few months, similar cracks developed. I figure my effort to protect the lens created too much heat trapped in the plastic.
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That's pretty wild. need to get a headlight visor, old school style