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Headlight disassembly - nondestructive?

848 Views 9 Replies 3 Participants Last post by  tengu
Hi,

has someone taken apart the headlight of an F800S/ST/GT without being destructive? Seems next to impossible to do.
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do you mean opening it up? usually the lens is bonded to the body so you would need to heat it up in order to remove it.

What's the purpose for wanting to open it?>
DJ123 is correct you need to heat it up. I struggled to dissemble one until I discovered this. I cut the external tabs of to begin with and still could not take it apart did a lot of head scratching and internet browsing and discovered the heat trick to break the glue seal. I heated mine in a conventional domestic oven. I found a post on a headlamp forum were members posted the temperature and time they left the headlamp in the oven for and the results of being able to dissemble I used this as a base for my own attempts. IIRC I had mine in the oven for 15 mins at 125 C, (be warned most doing this are USA based and will be giving Fahrenheit scale) after that it came apart no problem and I wish I'd discovered this before my first attempts to get it apart. If you want I can post some pics of the two halves of the headlamp so you can see what you are dealing with.
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This is exactly the kind of information I was looking for. Many thanks, I was about to take the cutting wheel to it.

@DJ123: Purpose is this: crashed the bike, headlight is fine, but jumped off the pin that is supposed to move it forwards and backwards. It now happily illuminates the sky instead of the road and the screw meant to adjust it is crooked. Which is weird, and I think that has been an issue before I crashed it, I just never had a reason to twist it. Anyhow, I might as well split it apart and see whether I can't figure out how to work around that issue.
you can reconnect it with the headlight in tact, mine did the same thing. Remove it entirely from the bike to gain access to the rear, and its a bit fiddly but do-able.
.......headlight is fine, but jumped off the pin that is supposed to move it forwards and backwards. It now happily illuminates the sky instead of the road and the screw meant to adjust it is crooked.....
There are three ball and socket joints that allow the silver reflector to be aligned correctly the trick to getting them on is that they are all at different angles to each other below is the back of the reflector the bottom socket needs to be pushed vertically downwards (from your description this is the one that's dislodged) the one above it needs to be pulled directly backwards and the third needs to be pushed at about 45 degree once you know which way to push your dislodged one you could be in with a chance of doing it without splitting the headlamp.

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I tried that, but the bottom bracket is stubborn and will not move after turning the screws some 3 - 4 rotations out. I can't get them further out, as I lack sufficiently bendy tools. To me, it seems I am locked in to this track. especially since any bump might upset the light to the point that I'd have to do it all over again.

Back to the issue at hand: 20 min @ 125 °C didn't do the trick, so I'm going for 150 next. At 175, it should come loose and the smell should upset anyone in a 100m radius, otherwise I'd be back to square one.
....Back to the issue at hand: 20 min @ 125 °C didn't do the trick, so I'm going for 150 next. At 175, it should come loose and the smell should upset anyone in a 100m radius, otherwise I'd be back to square one.
This gives some idea of times and temps that have worked for others, as for the smell I did wait until my wife was out for the day before starting this and it did take two sittings first time I got it started then as it cooled the seal reset so it went back into the oven and redone make sure you pre-heat the oven.

https://www.hidplanet.com/forums/fo...my-headlight-in-the-oven-for-how-long-how-hot
had the oven preheated had it in there three times for 20 mins each, had slowly cut out more and more of the glue but the damn thing wouldn't budge at that temp. Opted for 150°C, nothing still, went up to 175, at which point the clear glass up front starts to cook? At least it starts bubbling internally and thus becomes opaque. This unit is toast, then.
Oh well, time to hit up boonstra for another part. Let's hope they have an e-marked one.
alright, part is on the way. THanks for the help, everyone, even if it did not yield the desired results.
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