Topic: just got a 1980 cb900c, electrical question

[Hondawggie]

Just picked up a low-miles 1980 cb900c and the prior owner stopped riding it when all the power went dead (not due to a fuse).

He thinks it's a wiring issue in the front fairing.

I removed the fairing today.  There was a large white plastic connector that originated in the 900c's wiring harness in the headlight shell and was plugged in to a socket in the fairing.

The prior owner was not sure if the connector and wiring was stock (ie. the fairing manufacturer included a socket for a pre-existing stock connector and wiring from the bike).

I unplugged this connector and will simply stash it with the rest of the wires behind the headlight in the headlight bucket.

Can anyone confirm that the cb900c bikes came stock with an 'accessory' connector/wiring like this, ie. it's a 'cruiser' type of bike, maybe Honda foresaw people buying fairings for it. 

As a matter of fact, there is a plate on the inside of the fairing that says 'H O N D A'  in the factory letters/font.

[HondaMan]

Honda sold a fairing series called the Hondaline fairing during those years, made expressly for the bikes. They are identifiable: there is a long, horizontal lower edge to the sides, while the upper portion is steeply sloped. They have rectangular turn signal lens that are flush to the front of the fairing on both sides. They often have cracks in the mounting flanges where they bolt to the [very complicated] fairing mounts. The CB900 fairing kit included a 4 or 6 pound weight that bolted where the original headlight used to go when the fairing was installed, so as to not change the "feel" of the steering, Honda said... 

There are also air vents to bring cooler air to the rider, as those fairings were notorious for pulling engine heat up behind them on a hot summer's day, 30-50 MPH ride. 

The fairings came with a wiring connector and adapter harness: you removed the headlight and turn signals, installed the weight and its bracketry, hung the wiring behind the weight and plugged the harness adapter into the mate where the headlight and turn signals used to plug in (before you removed the headlight).

[Alan F.]

- what should I do with the wires and the big connector that plugged into a fairing I have since removed?

I'd just tape it up with electrical tape, throw a wire tie around it to keep the tape from unwinding on a hot day, and tuck it away somewhere out of site secured by another wire tie.
Connect your lights and stuff back up the stock way and see if everything works. You'll never find a problem to troubleshoot if you don't wire it up and try.


(If I were wiring up a fairing I'd just splice into the necessary wires as cleanly as possible to ensure reliability of my electrical system. It sounds like that's what you have there.)

You might want to put that set of lowers up for sale, I didn't know Pacifica even offered them maybe they're rare? (but what do I know...)
Alan

[HondaMan]

That's definitely NOT a Hondaline fairing. It's a Pacifico. Their fairing had a wiring kit that spliced into the existing wires, usually with those blue 3M clip-on splices. You removed the headlight and shell and mounting ears to make the fairing sit closer than a Vetter (or folded the ears inward if they would fit). This conversion will not cause a total power failure, though.

Most common on the DOHC bikes: the pins in the white connectors (all over the bike) are very small, uncoated, and easily pushed back out the other side of the plastic connectors when they are pulled apart and plugged back together. They corrode much more easily than in the earlier (and 10 year later) bikes. Many of those era have been parked (or worse) for electrical issues. Pay special attention to the big one on the back of the main keyswitch: it is the same as on the SOHC4 F0 and later bikes, up on the instrument panel. The contacts in those switches were also not rated for halogen headlight use, and often the Brown and Brown/White (spliced wires) contacts burn.

[HondaMan]

Thanks HM, it sounds then that if they spliced in to the stock harness the installer had the option of cutting off the stock headlight wiring and turn signals or leaving the stock wires intact and simply doing a true splice, ie. trimming off some of the insulation from around the stock wire then adding the new wire around that bared stock wire then taping it up.   If the installer chose the 'blue connector' option then I probably would *not* find that the stock headlight socket is still there, but it is (the stock headlight socket is still on the bike, *and* the fairing's custom wire harness also has a headlight socket.)

Very wise counsel from you about the pins, particularly the 'under-ignition' set.   So based on that my first step is going to be a check for power around the key switch then go from there.

The thing about the fairing is that electrically it's only got 2 turn signals and a headlight.  Not much to fail there.
I'm going to get back to it today and will probably find that it's the ignition connector.

This bike was parked *way* before its time, at 9000 miles on the clock.  It looks to be in very new-like condition albeit dusty.  He put the ad on CL this past weekend, 'free cb900' being pretty disgusted with it, the bike died in the middle of a long ride and he parked it and forgot about it in revenge I reckon.

Those "died in flight" symptoms are very common with the DOHC 750 and 900 of the era. Most of the time, I find the connector on the electronic ignition module, which contains the BLACK and GREEN wires, is severely corroded. The powder works its way from those power wires into the signal wires from the pickups, and they stop passing their weak signal to the box. The ubiquitous hi-pressure carwash has a lot to do with it all, and the cheap connectors that the bean-counters at Honda implemented after Sochiro stepped down sure didn't help.  In some cases, bypassing those connectors is the smartest thing to do...

[KingCustomCycles.com]

If you really feel sorry for the PO, send him a check for $500.  I have had two of those 900s and never did really use the high gears.  Just left them in low and drove as normal.  I will end with that as this is a SOHC site, and you have a DOHC.

[dave500]

other bikes section perhaps?ill ring the removal company now.