(Note: I originally made this upgrade in Oct. 2013. This post has been sitting in my queue awaiting editing since then.)
In the pursuit of ever more electrical efficiency with the '77 CB550, I decided to replace the stock 45W sealed beam headlight with an H4 fixture.
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| Front of the lens. Note the asymmetric pattern to keep glare for oncoming drivers to a minimum. |
The stock sealed beam light always seemed a bit dim to me, and the pattern it cast seemed a bit wasteful.
After some searching, I decided the best option was to go with the Bosch H4 motorcycle lens/reflector unit. This lens replaces the stock sealed beam light and accepts an H4 halogen bulb, and then mounts the same way the original light did.
A good source of info on the Bosch H4 unit, comparing the auto vs MC, and sealed beam vs halogen can be found here:
The P/N you want is 0 301 600 118. This has the correct beam pattern for a MC driven in the US (right-hand side of the road. The aforementioned website has a very in-depth analysis of the variations of the H4 light, pertinent federal and state laws, and the HB2 vs H4 bulb standards.
You will probably have to search a bit to find the correct part, as these usually have to be imported. I found mine on eBay. The one you want will be marked "DOT" and "Motorcycle." Find a listing that explicitly mentions the part number to be sure you are buying the right lens.
In short: the Bosch H4 lens with a quality H4 bulb will make a world of difference over stock, allowing you to see better and the other cagers on the road to see you better.
Truth be told, I was in a low-speed collision with a deer shortly after dusk in the Fall of 2014. If it hadn't been for this upgrade, I would not have had time to react in time. By the time I hit the deer, I had all but stopped, and only dropped the bike because I wasn't ready to be stopped quite yet. I estimate I was only doing 5-10MPH when I hit him. My gear protected me and I did less than $50 of damage to the bike.
When doing this upgrade, it also helps to cut back on other power hogs on the bike: running lights and tail light, by upgrading those to LEDs. This should also take some strain off the charging system, or at least not make it worse when going to a 60W bulb. There is at least one more upgrade you can make to squeeze the most out of your stock battery and charging system that I will write about in a future post.
Here are some pictures of the installation:
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| Back of the fixture. |
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| Another shot, showing the protective boot. |
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| Lens mounted in the frame, with bulb installed. |
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| Another shot of the completed assembly. Rubber boot has not been installed yet. |
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| Low beam. |
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| High beam. Note that you can still see the marker lights, which were LEDs when this photo was taken. |
That's all for now.
