term 85 and 86 control the red or hot(87a and 30) Now does everything work if you just pull the relay? or does it control something else. It sounds like you could do away with a lot of wiring. Dont just put the 2 reds together till you know. HD puts a lot of unnecessary wiring in that can be removed if you understand the systems.
For a time most anything we built and sent across the pond all ways had to have a way to turn a parking light on with nothing else and it could be changed side to side. I was told because the streets were so narrow you could leave just 2 small lights on all nite. Don't think you need that on a bike.

 

Parking lights are indeed a necessary requirement here, but only when parking on the street. I don't recall ever doing that with a bike, in over 40 years! Also in areas with street lights it is not normal practice. So let's not get hung up on why this relay is there! It was installed over 20 years ago......

As for bike electrics, I have owned several MZ strokers and the wiring on them has to be admired - or seen to be believed! I have successfully added parallel wiring to my Glide, for tourpak, gps, intercom, fog lights, HID headlight, but taking stock stuff away is something else!

I'll be taking a further look at this soon, before I pick up my wire cutters......

 

The book I mentioned has the diagrams in the back for domestic and International!!! Remember these books may have been printed before the person you were talking to was born, and lots of people don't even know they exist!!
John

 

The conversation I had with H-D UK was around 1993! I know of the type of book you mention. My manual has around 40 pages of wiring diagrams, including the FLHS, but not the International version of any model. It looks as if 99948-96 is still available, but it post-dates the FLHS.

I have however, following a momentary flash of genius, found #99948-90 'WIRING DIAGRAMS - 1986-1990 AL', but it is 55 quid - 85 bucks! I would need convincing the correct diagram is inside before buying one! I'm also embarrassed to discover John that you and I have had a similar exchange a couple of years ago about that very same book!

Does anyone have that magic -90 book?! I've never seen one. Is it really worth buying one?!

 

GR, you really need to spend a little less time in the pubs. Those pints are working on the brain cells!!!LOL!!! Check around some of the better indy's or Harley shops and see if someone has one laying around, that you can look at, or check E=Bay with a posted search. That way if it comes up you will be notified.

 

GR mate ... you are one of the most technically stout members of this site that i have seen.
I propose you forgo all the " possibly available book stuff " and follow the procedures advised by installing a " safety inline test fuse " of the appropriate amp. value and test the two red wires .
If the test fuse dosent blow and all else is to your liking you are good to go .
Cheers.

 

OMG - no pressure then! Thanks for the compliment, but I must try harder not to let my veil slip.....

I am already resigned to doing some electrical testing before picking up the snips. I have my lovely new Shorai lithium battery to fit (battery tray being made as I write) and several other electrical things to sort out. I have had to disturb a lot of stuff to get other things done, so need to prove everything is in working order. Then I can follow your suggestion.

As I said earlier I will study things around that relay yet more closely soon. I want to work out what those five thermal cutouts all do and check they are not wired together in some cunning way. The wiring on that top tree is very tight and not easy to follow. I did try to take a photo to post here, but gave up, as so much is obscured.

John, thanks for the suggestion regarding that book. With all the electrical stuff in mine (except International diagrams) I find it difficult to imagine what a book as expensive as my 84-90 manual is going to add! Also money is draining away at present on this bike, otherwise I might just buy it.

 

Graham you are correct in your first post.
30 – red (Power Feeder)
85 – orange (Control wire from switch)
86 – black (Ground)
87 – brown (Power to parking lghts)
87a – red (Power to ignition)

You can join reds and eliminate others. Switch probably used so you can operate parking light without ignition power and relay prevents a "dead short".

As always test retest and be sure before you remove any electrical these systems can be a mystery and most have been tweaked.
Cheers

 

Thanks Mark, my confidence is improving! Despite machinehed's kind comments, electrics are an area that I find needs more than a spanner.....

 

The logic sounds plausible to me as well. The relay switches from 87a to 87 when energized, but when not energized, it rests on 87a. This means that in resting state, the two red wires are directly connected to eachother. When you hit the switch, the relay is energized, shutting power off to 87a and sending it instead to 87. I wouldn't think you would even need a fuse in there, just connect the two red wires together and insulate them well and remove the rest of the un-needed crap associated with that system.