Many vintage Honda twins share the same problem: the factory headlight only seems to have three settings: dim, dimmer, and off. The factory Honda headlight buckets are also plagued by weak sealed beams, fragile plastic buckets, and a hard-to-find 6.25" lens. In this article, we walk through upgrading the original plastic headlight bucket and sealed beam to our modern metal bucket with a separate lens and replaceable H4 bulb so future service is as simple as a quick bulb swap. The example motorcycle is a Honda CB360, but the same bucket and general steps apply to many other Honda twins that used the 6.25" headlight lens.
Compatibility
The bucket shown in the video is intended for vintage Honda twins that used the 6.25" headlight lens or smaller 5.5" lens and have similar headlight mount spacing. These include, but are not limited to:
Honda CB / CL175 (some early models, often with 5.5" headlights)
Honda CB / CL / CJ360
Honda CB / CL350
Early Honda CB / CL450 that used the 6.25" lens
Tools & Parts
Basic metric hand tools
Wire cutters and crimp/splice tools (if upgrading from bullet connectors to the H4 pigtail)
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For CB360 / CL360 bracket modification
Hacksaw
File
Bench vise
Small paintbrush and enamel paint for touch-up on cut bracket edges
Step-by-Step Instructions
Remove the Original Headlight
Remove the small screws on the sides of the trim ring.
Swing the ring out from the bottom. The top of the ring has a tang that hooks into a notch in the bucket.
Drop it away from the bucket and remove the sealed beam assembly.
You should now see:
A three-prong connector (as on the CB360)
Three individual wires with bullet connectors
Unplug the sealed beam and set it aside.
Identify your headlight connector type
If your motorcycle has a three-prong H4 style connector - Unplug and reuse it with the new halogen or LED H4 bulb.
If your motorcycle has three separate wires with bullet connectors - Use the included H4 pigtail and either solder to the existing wires or crimp bullets to make a removable H4 adapter.
Free the “bird’s nest”
Identify the specialty nut ground connection(s) with green wires attached. Unbolt and save them to be reused in the new bucket.
Gently push the wiring out the rear hole of the bucket
Remove the original bucket
Loosen and remove the headlight bucket mounting bolts at the sides.
Slide the plastic bucket off the headlight bracket.
Modifying the Honda CB360 Headlight Bracket
Note: This section is specific to the CB360 headlight bracket shown in the video. On CB175 / CB350 / CB450 and similar twins with headlight brackets (“ears”) mounted on the fork tubes, no modification is needed to mount the bucket to the fork ears.
The new metal bucket has a slightly deeper profile at the top rear. On the CB360, the top “arch” of the stock headlight bracket interferes with the back of the new bucket, so a small portion of the arch must be removed.
Remove the headlight bracket from the motorcycle
Unplug the front turn signals from the harness. Disconnect the speedometer and tachometer cables for easier access.
Remove the remaining fasteners holding the headlight bracket to the upper and lower triple trees. Slide the bracket assembly off the motorcycle.
Cut and Paint the bracket arch
Use a paint pen to mark straight cut lines down from where the curve begins on each side of the upper triple tree mounting holes.
Clamp the bracket in a vise and cut along the lines to remove the thin center section.
Use a file to smooth and round the cut edges and remove sharp corners.
Clean the area and brush on enamel paint over any bare metal. It is a good time to touch up any other chipped areas while you are there. Allow the paint to dry fully before reinstalling the bracket.
Reinstall the headlight bracket
Reinstall the headlight bracket and snug the mounting bolts, using the correct spacers and grommets.
Reattach the tachometer and speedometer cables and any wiring that was temporarily moved.
Installing the New Metal Headlight Bucket
Feed the “bird’s nest” of wiring through the main hole in the back of the new bucket. The new bucket has a large opening, which makes routing the harness easier than the original..
Shim the bucket to match the bracket width
CB360 - The new bucket is narrower than stock so use the included washers to create spacers. One washer goes under each new mounting bolt head. Three washers go between the bucket and the inside of the headlight bracket on each side.
CB175, CB350, and CB450 - The headlight ears adjust to fit the bucket so spacers may not be necessary. If your OEM headlight uses the turn signals as mounting bolts, the turn signals can be threaded directly into the headlight bucket threaded mounting holes.
Reconnect turn signal wiring and running lights
Reconnect any wires that were unplugged while removing the original bucket and bracket. Take care to route things so they are not pinched against the inside of the bucket or lens.
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If your motorcycle came with the specialty grounding nut connectors, thread them on. Reconnect the green ground wires to the harness.
On one-piece brackets like the CB360, one ground tab is enough. On separate left/right ears like the CB175/350/450, use a ground tab on each side so both signals have a good ground.
Note: If your original ground tabs are missing a simple ground jumper can be made. Use a ring terminal on one end and and male bullet connection on the other. Connect the bullet to an open ground female connection on the harness ground circuit. Bolt the ring terminal to the headlight mounting bolt and secure it with an m10 x 1.25 (fine thread) nut. Remember to make one for each side if needed.
Install the Bulb (Halogen or LED) and Lens
If installing one of our H4 LED bulbs, release the spring clip holding the halogen bulb and remove the bulb. Install the LED H4 bulb in the same opening, align the tabs with the slots in the lens, then secure it with the spring clip. The rubber shielding boot will not fit over the LED bulb’s heat sink and is not needed.
Plug the H4 pigtail or original three-prong connector onto the back of the bulb.
Place the lens and trim ring assembly in front of the bucket. Engage the top tang of the trim ring into the notch at the top of the bucket, then swing the bottom of the ring and lens inward.
If you feel resistance, stop and gently rearrange any wiring inside the bucket. Do not force the lens into place. Once the lens sits flush, install the side screws and tighten them evenly until the trim ring is snug.
Final Checks, Aiming, and Notes for Other Models
Functional test
Turn the ignition key to the “ON” position. Check that the low beam, high beam, and front turn signals and running lights are functional. If the turn signals misbehave recheck the ground connections from the green wires to the bucket and brackets and the blue/orange connections for each signal
Aiming the headlight
Park the motorcycle a 20 - 30 ft from a wall. Sit on the motorcycle, loosen the side bucket bolts slightly, adjust the bucket up or down to position the beam on the wall where desired, then retighten.
A note on bulb options and wattage limits
From the factory, these motorcycles use sealed beam headlights around 35 W. The charging systems on these Honda twins are weak, and 35W is the maximum headlight draw they are designed to support. Using a 55–60 W bulb can overtax the charging system. The headlight may be brighter, but the alternator will struggle to keep the battery charged, especially at lower engine speeds.
Parts you might need
6.25" OEM Headlight Bucket H4 Upgrade Lens