Headlight Question

arfingdog

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I've looked through some of the headlight threads, but my question is more basic than "I want more light" etc. I'm not sure I understand what the hell I've got on my 79 400F--it doesn't appear to be the same as the Yamaha parts page. The headlight "lens assembly" in my case (see the pic) includes some mounting tabs as part of its frame and the "bulb" is also a permanent part inside the lens with soldered leads coming out instead of 3 male bayonet connections like I'm used to seeing.
How do you replace this? I like the OEM bucket. I purchased a 7" unit from Mike's but it has no way of mounting in what I've got. Any advice welcome.
Tom
 

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I'll shorten my question. Is that the "normal" light assembly? With the bulb, lens and mounting bits all permanently joined together, how do you replace? Or is there an aftermarket reflector/mount combo that allows an H4 bulb or something?
 
That's normal. The whole sealed beam lens assembly gets replaced. There are some on eBay.

The only almost-direct-fit aftermarket H4 lens is now out of production since their plant is in the Fukushima exclusion zone.

Some members have cut the bulb out and affixed an H4 bulb assembly in the stock lens.
Some 7" aftermarket lenses or LED bulbs can be made to fit with some modification.

I bought a 5-3/4" LED headlight and bucket but not all the electrical connections fit inside.
 
Thanks @BBS360. Amazing to me that they did it that way. Luckily, the current bulb is still going, though seems to be about 1 candlepower. I *might* think about the whole cut and fit an H4 thing while keeping an eye out on ebay.
 
You can possibly desolder the bulb from that reflector and replace with a 9003 bulb. The old bulb is quite a bit larger than the opening when trying to pull it out. Just pull it and break the bulb (use a gloved hand), and the glass shards will shake out. Depending on your new bulb, you may be able to resolder it or just JB weld it in..
 
Pretty much most smaller Japanese bikes used soldered one piece bulb assemblies until the later years when replacement bulbs began to come out. I never ran across replacement bulbs until my DOHC 750 Honda in '81.

The early are usually glass as you have to hold vacuum in the assembly for the light element to last longer than a few seconds. Some have a steel back bowl if the glass is a smaller enclosed globe inside.
 
I can understand the sealed beam with reflector and bulb in one sealed unit...after all, cars had them for years. It's the adding of the ring and mounting bits that strikes me as odd, because that makes it proprietary and complicated. Or maybe proprietary is what they were going for.
 
I chopped mine to replace with a later FZR bowl, surprised the bowl was metal too. Should be fairly easy to remove the lens, can't remember how I removed mine but heating it in the oven should soften the adhesive and ease separation. You could get an old H4 unit off ebay and cut out the mount with a bit of flange around it and then after removing the soldered bulb from your old unit enlarge the hole enough to get the H4 bulb in and adhere the new bowl flange to the old bowl. If you weld it the chrome will burn/flake off in the bowl but you could touch that up with some mirror effect spray paint. Or you could epoxy the bowls together..
 
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