POST 3: Blue bike; Wiring and Electrics

Abandon hope all ye who enter here!

The electrics on this bike are fiendishly complicated. I dont think they need to be, my NSU has a loom of 4 wires, but Honda beg to differ. In my case the situation is even worse since some components have been removed and the wiring disconnected and/or cut. Frankly its a mess and Im not sure I can sort it out although I will try.

The Nacelle (Pod)

It seemed to me that a good place to start would be the nacelle wirings and ignition switch etc. Given the damage my bike has suffered its unlikely that what follows weill be much help to most owners whose electrics have not been similarly chopped. Consequently the next few pictures are for my records and hopefully help me with reconnecting and re-packing the loom into the various bike components, specifically the pod and headlight housing, as well as assisting with cable routing.

Disconnected wiring forms two clusters at the front

The nacelle pod is reasonably intact although I have no key and so will need to fit a new ign switch. The high beam light is depessed out of position

The pod is held on simply by a 6mm stud passing through the pod and front carrier. This doubles to hold the basket retainer. Its a double ended stud that has a nut on the front- in this case its been replaced with a square nut which I'll swap back to a hex.

Remove the nut and slip the carrier off the stud

The stud then unscrews and releases the front of the pod.

Nut removed and releasing the basket holder

The stud unscrews by hand- note the double ended form.

The rear of the pod is held by a clip stud- its a close run thing between releasing the stud by levering the pod side forwards and cracking the pod. Luckily I got away with it.

Rear retention tab and its slot.

Removing the pod revealed a mass of spaghetti and entomology! The speedo cable holds the pod in place but is easily unscrewed.

Speedo cable unscrewed. Note wiring for speedo lamp and one warning light... the other having been removed.

Space inside the nacelle is very limited as it houses the ignition switch, indicator and high beam warning lights and the speedometer. I needed to strip everything out and I think there is a best order in which to do this: Remove both warning lights, Remove the speedo and finally remove the ignition switch.

Each warning light is held by a single screw which should simply unscrew to release it. Unfortunately in my case both screws were loose in the plastic and one mounting pillar had broken off so removal was no simple task. In the end I just pulled the screw heads up and out as unscrewing was impossible. This popped the screw out of the pillar which it has probably destroyed in the process. Ill have to devise some better way to reattach when I rebuild.

High beam light with remnants of the mounting pillar attached.

Likewise the indicator warning light.

Warning lights removed.

The speedo is held by a spring clip- just lever the spring inwards (towards the speedo) using a flat bladed screwdriver and the speedo will pop out upwards.

There was no obvious way to remove the ignition switch. However as I needed to replace this it wasn't particularly problematic if it was destroyed in the process. The ring trim just popped off with a screwdriver- there was an indentation in the edge for this purpose.

Although I didnt know this at the time the switch is actually in 2 parts- a key-operated metal section that is spigoted into a plastic body which contains the electrical parts. Here in this pic Ive cheated and reassembled the switch after Id finally got it out. The metal (key hole) section is clipped into the wings of the plastic section with two metal projections. These wings also clip the plastic section to the nacelle.

Im still not sure how this switch ought to be removed if you wished to do s without damage. I suspect the best way is to ease the plastic wings away from the body of the switch thus disengaging the metal lugs above. The metal section can then be pulled out of the top. The plastic wings can then be pressed into the void where the metal section had been, detaching them from the nacelle. The plastic section can then be pulled out downwards out of the pod. If removing an orginal switch again I'd start by locating these lugs and pushing the plastic wings into which they are clipped outwards to release the metal key section. This isnt easy as access is limited so you have to use screwdrivers. The separated sections of the switch are shown below.

Frankly I don't think this information will necessarily be useful because the new switch is a pattern part and comes in one piece. I detached the wiring so that the parts could be separated and took a few views of the connectors I released.

Ok so its a mess but there are some unifying points that I hope will help.There are 4 wire loom bundles; one comes from the rear of the bike through the frame. It emerges on the rhs just below the handlebar mounting. There is one from the lhs lighting control and one from the rhs lighting switch. These two are coiled round the handlebars and I think that will be crucial in getting the wiring to pack into the nacelle pod. Finally there is a grouping of 6 wires that go down to the headlight body. This includes the two power leads to the front indicators (one orange lhs and one light blue rhs). Sadly both were disconnected so I restored connectivity ro the 4 way multiplus f those colours. In fact I later dound the orange was too short for re onnection and replaced it with a red lead.

Green wires are ground... there are loads of them with a multiplicity of conectors that worried me greatly. In fact they are simply all connected together somehow, so the actual junctions you use aren't that important.

Feed from the bty to the ign switch is red BUT power distribution from the ign switch to services is via Black wires. These are joined at a very inadequate combination spade and 5-bullet bus... I will change that because I dont trust it.

Note the Lb and Orange power feed to the front indicators is completed via differently coloured wires already wired in to the indicators, and for these the ground connections are black. This breaks with the black=power, green= ground convention probably because these are second hand indicators from an unknown bike.

I could restore most of the wiring connections simply by matching the colours although there is one oddity... according to the wiring diagram, the feed to the balancing resistor from the lighting switch terminal "R" starts off brown, becomes green "at some point" and finally converts to pink heat-resistant wire beneath the rear light where it connects to the resistor itself. I suspect this is an error and in fact this wire is green from the start until it reaches the pink heat-resistant section but I'll check.

In my case the wiring for the rear indicators was present but the fronts had been disconncted

I needed to lengthen a few wires that had been cut too short and where possible I used the same or a close-match colour. I then installed the new ign switch. However I have no idea how to route and bind this mass of wires to fit into the nacelle neatly. Sadly the old pattern was really no help as it had been so badly hacked.

I fitted a battery and immediately the rear light came on... this turned out to be the front brake light whose switch was activated as the front brake cable was missing. I tied the lever back and it went out. Testing the lighting switch I found that the front posn light illuminatedin the "P" position but nothing else, and the headlights were inoperative. This concerned me greatly but it seems that the headlights and tail light are actually powered directly from the alternator and thus will not work unless the motor is running.

The battery powers only the horn, rear brake and front position light as already noted and the indicators. Operating the indicators showed that only the lhs was working so I'll investigate that later. This (and the inoperative horn) turned out to be cause by dirty contacts and bad earth connections so I cleaned them and result!

In order to refit the warning lights into the pod I made 2 of 1/2" nylon spacers drilled through at 4mm to install using anodised M4 Allen flange cap screws.

I could install these beneath the warning light inserts in place of the original mounts and secure the warning lights using a nut inside the pod. This looked quite neat but I think Ill change the stainless for black anodised screws