Headlight Information Needed

Hi all.

Some background - The New Zealand Government is law crazy and from November has required motorcyclist ride with the headlight on at all times or a big fine. Don't get me wrong I usually do this anyway but I'm annoyed that it will cost me money if I accidently forget.

My XJ750E-II is basically an XJ900 with the 750 engine, I'm trying to figure out a way to leave the lights switched on but not during the start for obvious reasons. There was some talk previously about USA models of the 550/650/750 headlight relay doing this, can someone confirm this? Also the XJ900 wiring diagram (same wiring as my 750E-II) doesn't show a headlight relay, can a 900 owner confirm this?

From what I can see there is no relay, power runs from the Main Switch thru the Headlight Fuse to the Headlight Switch and then to the Low/High Beam (Dimmer) Light Switch and then to the Headlight Lamps.

Ideally what I want is to leave the Headlight Switch in the ON posn but not have it on until after the engine is running.

 

Heres some pictures which may help:

 

I wish I knew the answer to this one. one of the wizards here should be able to answer, though

 

my 550 has the set up you are looking for, the light comes on when you turn the key to on, the light turns off when you hit the starter, and comes back on upon starting. ive never seen it happen since im having some relay issues right now, but it doesn't seem like it would be too hard to wire a relay into the mix.

 

Basically, what the US models have is a relay that supplies headlight power that is wired up so as to be latching. In other words, once it closes, it will feed power back to its own coil to keep itself closed until the main power of the bike is shut off. The initial power to turn it on, though, comes from rectified power directly off of one of the alternator windings (white wires).

Here's a sample schematic of what I'm talking about:

This assumes that your alternator, like those on the older XJ's, uses a field winding rather than a permanent magnet. If you have a permanent magnet alternator, then this circuit will require the addition of a series resistor and a parallel Zener diode to protect the relay from excessive voltage from the alternator.

Oh, by the way, 86 goes to ground (Black).

Cheers,
Paul

 

Your simplest fix will be to replace the headlight switch with a NC relay.

:

Wire the headlamp to poles 30 and 87A. (likely you'll find what's called a SPDT relay which will also have pole 87 on it, insulate that pole as it's unused). Connect poles 85 and 86 to the two smaller gauge wires going to the starter relay.

The headlamp will be on except when cranking the starter.

 

I have a Canadian model Which has this feature. Sent you a PM.

 

Why send a PM on this, rather than sharing information where others can benefit?

 

New to forum and haven't figured out how to attach the schematics for my bike. I will share whatever I have with whoever needs it. Just wanted an e-mail address to send to. Lopezfr2 has already received them to assist with his lighting issue and sent the clutch info to laxjosh1223. I want to keep the picture size to that posted in the forum rules and that might be hard to read.

 

Sign up for a photobucket account so you can imbed pictures directly; it's free. But be nice and don't imbed anything bigger than 1024X768.

http://photobucket.com/

 

Thanks for all the replies guys. I can see the logic in both diagrams. I'm most suprised that the XJ900 doesn't have a headlight relay?

 

Hi Kiwi. You have another set of schematic on the way. They should be there soon (in living colour).

Thanks for the advice on the photo site bigfitz52 - shall do

 

Elegant solution!

Mike

 

I agree Mike, the SPDT Relay looks the simplest solution, I assume either 85 or 86 must go to earth if the other goes to the starter relay? I also wonder if I should provide some form of protection for his side of the circuit?

 

No. The relay coil would be wired in parallel to the starter solenoid coil. The point is that when the solenoid is activated, the relay is as well, with the relay disconnecting power from the headlight while the starter is engaged.

End result would be headlight on when the key is turned on, but headlight off during cranking, then on again as soon as you take your finger off the starter button.

 

Thanks for all the good info SQL, just so I have this right:



Pins 85 & 86 would be connected to points C & D of the diagram?

 

For the setup that MiCarl suggested, yes.