Topic: 76, 750F, Headlight flashes once when I apply brake light?

[1976cb750f836]

When applying the brakes , the headlight flashes once? All original harness, I've unplugged and repluged all connections. I'm thinking maybe it's the voltage regulator?  Bike doesn't charge below bout 2000 rpm. Is this normal? Is their a more modern VR to replace these old mechanical ones? I do have a LED headlight,  should draw less current than stock?
I rarely ride after dark, so it's not super important, but if it needs a regulator I need recomandations. New battery last year, charged it once, after 3 months sitting through winter.
Charging system keeps it hot, I never have to use the kicker, unless I'm showing out?

[ekpent]

 There is an automatic feature in the starter button circuit that shuts off the headlight when it is pushed in.Maybe something screwy or crossed up there. It just shuts off and comes back on quickly ? Does it happen with just the front or rear or both ?  Might be something along the brake wiring path also.

[Don R]

 LED's normally use less power so are susceptible to a corroded connection, maybe a ground?

[seanbarney41]

I have seen lots of bikes and cars with the older points style electro mechanical voltage regulators do this.  It is just the points sticking or hesitating for a split second.  Sometimes it gets worse, other times better.

[bryanj]

 The regulator is not connected in any way to the headlamp and cannot make the light flash.

[1976cb750f836]

I got to thinking, Flash might be the wrong word, Dim is a more accurate description. But it only dims for a second, then returns to full bright, even while holding on the brake.
Also forgot to mention, I have some non stock brake lights. My brake-tail, is a repo T-model ford, with a 1157 bulb, I have 2 small bullet lights, 1 ea side, that act as a aux brake only light.
Could these 3 lights together, cause a high current drop when they come on? Causing the light to dim momentalary ? Maybe I should find LED replacement bulbs for the 3 lights, then current drop should be minimal ?
Ps-what about an electronic VR replacement? Anyone done this?
Thanks  And is no charging below 2k normal?

[robvangulik]

How many watts do those three lights draw combined?  One 21 or 23 watt lamp, depending on country, is standard, when you use three times that you outshine your headlight....

[1976cb750f836]

Ok, my 61 years of age , are affecting my memory, I already have a modern VR, installed 3-4 years ago. Haven't measured the current draw of the 3 lights, but that's gotta be the problem.
This only happens when idling, and the charging system is not charging. If riding at 3000rpm, and brake applied, hardly any change in light. Must be the weak charging at low rpm causing this.

[1976cb750f836]

I have the exact same setup(Headlight and 2 aux brake lights) on my 81 gs750. Headlight does not dim, but battery is charging at idle.
I think I'll ride and not worry bout it!

[PeWe]

Not enough with one brake light 21W?  If 3, 7W each will be less visible. Rear light is 5W.

Blinkers adds some load too, 2x21W when used. I have a volt meter on my bike (CB750 K2) where I can see how this affect the voltage level and the time it takes to resume voltage after some +4000 rpm cruising.

[1976cb750f836]

Is their a fix (Rickey stator), or else, so they charge at idle?

[seanbarney41]

Don't let it idle

[1976cb750f836]

It's really a moot point . Since the 836, and cam change, it falls on its face below 3500rpm.
Starts pulling well then, when riding I don't lug it, tell others when they ride it,to keep above 4k.
Is their similar to stock switch gear with a headlight switch?
My 81 gs, had the switch inside, blocked, I just un blocked and it now is manual.

[seanbarney41]

Easy enough to add a switch inline.  Or, use controls from a k4? Or earlier but that will require some fairly custom wiring and a good knowledge of the differences to your wiring

[Don R]

 On my 400F I used the JDM/euro right control/headlight with the off/park/on switch.  It takes a little creative wiring. You need to find the jumper Honda used to go around the blank control. But I also added the parking lamp. 

[bryanj]

Get a UK model rh switch from somebody like DS (NOT a pattern one) and look at the UK wiring diagram it will plug straight in and you can then turn lights off.
I say NOT a pattern one as the wire colours are frequently different and make it difficult to work out!

[PeWe]

My EU K6 has headlight switch with 3 functions, off, parking, on.
Hi-Lo on left side.

It has a Hella reflector with LED parking bulb that takes only 10W but still very visible daytime. China LED H4 OK on dark roads, 30W. I saw difference how it charge compared with std bulbs.

My K2 has same reflector setup, but no parking from bar switch, only when parked, ign switch in park mode.
Light off, Lo, Hi

[1976cb750f836]

My EU K6 has headlight switch with 3 functions, off, parking, on.
Hi-Lo on left side.

It has a Hella reflector with LED parking bulb that takes only 10W but still very visible daytime. China LED H4 OK on dark roads, 30W. I saw difference how it charge compared with std bulbs.

My K2 has same reflector setup, but no parking from bar switch, only when parked, ign switch in park mode.
Light off, Lo, Hi

I like the idea of keeping it on the left side. Leaving right control switch stock.
Where can I find  EU K6 switch? Is the clutch perch a part of switch?

[bryanj]

You dont get on off on lh switch it is ONLY on UK rh switch, try Dave Silver.

[Don R]

my 400F right control..https://photos.app.goo.gl/P82AxQbZgffG3s9q7

[1976cb750f836]

My EU K6 has headlight switch with 3 functions, off, parking, on.
Hi-Lo on left side.

It has a Hella reflector with LED parking bulb that takes only 10W but still very visible daytime. China LED H4 OK on dark roads, 30W. I saw difference how it charge compared with std bulbs.

My K2 has same reflector setup, but no parking from bar switch, only when parked, ign switch in park mode.
Light off, Lo, Hi

How bout a pic of this left switch?