Try our new info resource - "Aladdin's Cave" (Main menu)Just added a separate link to Ash's Dropbox thread (shortcut)
I don’t know if this is the same but my 74 550 had a sealed beam.I bought a pair of standard 7 inch headlights for the original shape Mini for about £25 ish.One fitted perfectly in a couple of minutes, no modifications.One went to my mate for his Triumph.
For the observant, yes I know who the trader is. But he knows what will fit what as he's trading this stuff regularly.
Also found this one as I was searching. From memory Japanese 400s of the era had similar sized headlights, was searching for Kawasaki kh400 and this site came up, but also sells the Honda specification unit.https://www.ebay.co.uk/itm/Honda-CB400-4-CB400F-Four-Headlight-Head-Light-Glass-Chrome-Rim-/302151235792
https://www.ebay.co.uk/itm/Honda-CB400F-400-Four-400-4-halogen-headlight-new-unused-PRICE-CUT-/392959559525Would get you going at reasonable cost.For the observant, yes I know who the trader is. But he knows what will fit what as he's trading this stuff regularly.
https://www.ebay.co.uk/itm/Honda-CB400-4-CB400F-Four-Headlight-Head-Light-Glass-Chrome-Rim-/302151235792I have a USA 400 f, I fitted the above headlight to it, works great, a lot better than original sealed beam.I tried fitting a DS light but it will not fit in the US model rim