81 special relays

[RS Thornton]

I am putting an 81 special back together and have a question on a relay. The connection is near the battery, in the same area as the signal cancel unit and seems to match up with headlight relay that is up at the front over the coils. I have a relay that fits there and with it in the starter works. The same relay works in the headlight relay connector. I cannot seem to locate this relay in the wiring diagram or in the Clymers. Does anyone know if the headlight relay and this (starter?) relay are the same part? Or if they are different how to know which is the starter relay and which is the relay for this other spot.

TIA
Scott Thornton

[randy]

Best advice I can offer is the starter relay has two large (10mm) nuts on it. The headlight relay has four straight prongs on it. AFAIK, they do NOT interchange. The plugs are WAY different.

[RS Thornton]

Not the solenoid

Randy,
I think you are talking about the starter solenoid that lives under the side cover just to the side of the fuse block. This other relay spot I have is under the seat in the air box snorkel area. I do not remember it on my 78's or my 79's so I am wondering if this is some change particular to the 81's, kind of like the different coils.

Regards,
Scott

[TopCatGr58]

Hey Thornton,

On the 81's, there's an extra flasher relay because of the Emergency 4 way flashers as well as the turn signal flasher relay, and I think that's what you may be finding. I checked the microfiche, and that's the only other RELAY there, there are other devices like the signal cancelling unit, or headlight checker unit, etc.!
T.C.

[XSPastor]

I am putting an 81 special back together and have a question on a relay. The connection is near the battery, in the same area as the signal cancel unit and seems to match up with headlight relay that is up at the front over the coils. I have a relay that fits there and with it in the starter works. The same relay works in the headlight relay connector. I cannot seem to locate this relay in the wiring diagram or in the Clymers. Does anyone know if the headlight relay and this (starter?) relay are the same part? Or if they are different how to know which is the starter relay and which is the relay for this other spot.

TIA
Scott Thornton

I think the one you might be referring to (not a relay but a switch) at the front over the coils is the tip over switch isn't it? Like TC said, the hazard flasher (not to be confused with the turn signal flasher just under the fuse box in the right side cover) is located just forward of the signal cancelling unit.

[rlundy]

Don't these bikes have a relay unit that reads the condition of the headlight bulb and manipulate the high/low beam depending on status? Am pretty sure my '78 E has this relay, it's spoken of in the owners manual. Did not think this would affect the ability to start though.

[RS Thornton]

Starter interlock?

No, it is not the hazard flasher or the tip over switch, I have both of those. This phantom relay would mount kind of between the signal cancel unit and the hazard flasher in the area of the snorkel on LHS. The hazard flasher has 2 prongs at 90 degrees and connection in the wire harness is 4 parallel blade in banks of 2 just like the headlight relay. I am thinking that it is part a starter interlock the keeps the starter from working unless you are in neutral or have the clutch engaged. There is a switch on the clutch lever in this bike that I also do not see in the schematic. The headlight relay works in that spot, so I can get everything working so worst case is I rob the headlight relay off another bike.
Regards,
Scott

[RS Thornton]

To RLundy

They do, that is the reserve lighting unit and it is under the gas tank, just forward of the regulator/rectifier.

[XSPastor]

Sounds like PO made some modifications...

[XSPastor]

Are you working on a midnight special?

[RS Thornton]

Tim,

Modifications is the polite word for what the PO did to the electrical system, so I got a replacement harness from Andreas and started over. The S/N on the bike means it is a special but not sure if the wiring harness or clutch lever mount is different between the SH and the LH.
I found some interesting things on some schematics late last night, it looks like this relay is part number 4H7-81950-01 and it is in the 81 midnight special parts lists but not the 81 special. The switch on the clutch is shown for both the special and the midnight special in the parts list schematics. Do you know if all 81 specials had that switch on the clutch or if it was unique to the midnights.
So, I got my first answer and that the relays have different part numbers, now I need to figure out which of the 2 relays I have
Regards,
Scott

[randy]

Are you sure it's a relay? Could it be the flasher canceling unit?

[Shappers]

I have the European Sport edition and just where you are describing sits a "Starting Circuit Cut-Off Relay". Just as you stated it stops the starter from working unless the bike is in neutral or the clutch is pulled in.

Check out my WIRING DIAGRAM and you can check from the colour of the cables if your wiring loom needs the same type of relay.

[RS Thornton]

Thanks

That looks like that circuit matches what I have. Thanks for sending it.
Scott