electrical problem with 1978 1100

[skatman]

Hi everybody, I just bought this 78-11 bike back that I sold 21 years ago. but it's not running. My battery is not charging so I went to your tech help and I'm following what it says to do. While I was working on this with the bike turned off I noticed the headlight relay was hot. So i disconnected the connector and found the yellow wire was hot. Is it supposed to be this way?
Can anybody help me with this problem? Thanks for any help you can provide.

Sam

[TopCatGr58]

Hey Sam,

That yellow wire is directly from the alternator, but it shouldn't be "HOT" as in WARM/TEMP. You'll need to check the wires in the headlight bucket, they can get chafed, worn, could be causing problems. Also check your MAIN Ignition switch, as well as the handlebar wires inside the control cases! Also, your REG/RECT unit may be faulty? Be sure to check and clean all of the connectors for the charging system, as well as the battery cables, frame ground cables, engine ground cable. Lots of electrical gremlins are just poor connections!

Do you have a service/clymer's manual? If not, then send a PM or email to me, and we'll get you a copy of the wiring diagram for your 78!
T.C.

[skids]

Re: electrical problem with 1978 1100

Take a peek at Clymers page 179, top diagram. The headlight should not get current unless the key is on AND either the light switch is on or the bike is running. The yellow is from the alternator which can not have electrical current (normally) unless the alternator rotor is spinning, in a magnetic field (i.e. engine turning).

Originally posted by skatman
Is it supposed to be this way?
Sam

[trbig]

I have had stator and reg/ rect problems lately. Since my bike has not been charging, every time I start it now, the same relay gets very hot on mine.... hot enough to slightly melt the plastic. Don't know what it has to do with it... but it I don't ride around the block because of it. Still waiting on my stator... *Sigh...



Tod

[skatman]

TopCatGr58 - I'm thinking you're right about the reg/rect unit, because I did that check tech tip on the alternator (and feeler gauge). It checks out ok. I have the vetter fairing off (to work on the bike) and checked the headlight connector pins. Two were hot. Probably has something to do with that headlight relay being energized. I guess I will order a new reg/rect unit from the person who I read about someplace in this forum that builds them (Geezer?). I hope this will solve my electrical problem. Oh, I did clean all connections and grounds when problem appeared.
Thanks for the offer, but I have a Clymers Manual, I'm just not too good at reading electrical prints.

Skids - I looked at that but couldn't understand it because it looks like its coming from ac generator to coil and then to ground. Wouldn't that be ac? When does it convert to dc? Maybe I'm thinking wrong.

Tribig - From what little I understand all relays get a little warm while in use, as with the headlights on. When they start getting really hot I think that means they're going bad. Learned that from working on solenoid operated air and water lines at work.

Thanks so much to everybody
If this resolves the problem, then I'll be asking you guys about the smoking problem out of my left exhaust pipe. But one problem at a time. Sam

[TopCatGr58]

Hey Sam,

Did you check your charging/volts at the battery with the engine running? Are you NOT seeing 14 volts when hitting 2500? IF these are true, then a REG/RECT replacement is probably in order, but I didn't want to suggest getting one until you had checked it out! Geezer/Tony is the one that makes and sells these heavy duty things with lifetime warranty!!

I fried one of mine out years ago after putting on a few too many running lights! How many extra lights are you running? Of course, as Tony says, these things can just fry anyways, heat and less than top quality parts in the OEM's!

That yellow wire does come from the AC generator, but it's not AC, the white wires are the ones from the Generator that are AC, and in the later years, Yamaha put a DIODE on it before it went to the headlight relay to convert it to DC! But don't feel bad, I have a hard time reading these diagrams also!

Okay, we're ready with your three step program to help you stop smoking!!
T.C.

[Geezer]

Before you buy anything, clean every connector in the bike and coat the terminals with silicone dielectric grease. Most of the time hot and melting wires & plugs is a high resistance problem.

I'm also a big fan of taking an ohmmeter and testing everything that you can find specs for. It's easy to do and one of the best meters out there (an analog unit from radio shed) is only about 19 bucks. Also a good meter in the toolbox is a handy thing to have around and you'll wonder how you ever got along without one.

Age is probably the biggest reason electrical components fail. Also the design of the original R/R unit puts all the heat from the rectifier into the regulator. While they are still in one unit on mine, I leave a small breezeway in-between them.

I've written a bunch of articles and put them on my FAQ page at OregonMotorcycleParts.com . Check it out and feedback/critique is welcome.

Geezer

[trbig]

Check it out and feedback/critique is welcome

Man... where was that offer when I was buying from you!?!? Just kidding Tony. I appreciate all your help.... SO FAR! Still waiting to hear something back from the stator.

Sam, here's the testing Tony (Geezer) had me do... let him know what you got and he can guide you from there.


First off you will need a volt/ohm meter. Take 20 bucks down to your local Radio Shed and get the analog meter that's just under 20 bucks. You could get a digital meter but I think analog meters are easier to use for bike stuff.

With the meter in hand, unplug the wires from the alternator. There should be about an ohm resistance between the white wires and infinite to ground.

Next test the resistance between the green and brown wires from the alternator. This is for the field coil and should be around 5 ohms. I don't have my manual on had at the moment but these numbers should be very close.

Assuming you've gotten good news from the previous 2 tests, make sure the terminals are clean and plug the connectors back together. Turn the ignition on but do not start the engine yet. Place a .002" feeler gauge flat against the center of the alternator cover. If it is magnetically attracted to the cover, you're half way there.

Fire up the engine, put the volt meter on 25 volts DC, insert the positive probe of the meter into the back of the plug on the reg/rec unit (still plugged in) and the negative probe to ground. Rev the engine and you should see the voltage rise to around 15 volts at about 4000 RPM.

If it’s not charging at this point, the regulator is probably good but the rectifier is probably bad. Unplug both plugs to the reg/rec, set the meter to ohms x1, touch the positive lead of the meter to the red wire and the negative probe to each of the white wires. At this point you will either get continuity or not but it should be the same on all 3 white wires. Reverse the test leads and do the test again and now you should get the opposite results but again the same on all 3 white wires. Now you’re half done, do these to test with the black and white wires.


Tod

[skatman]

T.C.

I probably should give you a little history
Bike has been sitting for about 3-4 yrs. I bought it back, including a motor, front fork and wheel, rear wheel and drive shaft from another bike he had.

I put wd40 in spark plug holes let sit for a couple days.
Went on internet to find battery; found the xs eleven forum by chance and the no.’s for battery.
Removed carbs, float bowels, and cleaned with gumout. Fresh gas in tank, added in line filters.
Changed oil and filter
Started bike ran a little ruff, decide to take a spin around neighbor hood,( forgot how good that felt) see if it would clear up.
When I got back left exshaust was smoking like a 2cycle with too much oil in it.
Couple days later check compression 1-130,2-140,3-150,4-130.
Started bike running ruff, now the tach is not working, engine warms up starts smoking, fills garage (wife says that’s it).
A few days later bike wouldn’t start battery low, charged battery, put back in bike started bike check to see if it was charging.
Not charging, removed tank, seat and fairing. Check and cleaned all connection and grounds, that’s when I found the hot light
relay.

The former owner added shields to keep your legs warm. ( I forgot what they’re called, Senior moment).They have 3 little lights on each side, and also added a cigarette lighter

Did the testing on the alternator, readings came out good. That’s when I wrote the forum for advice. I think you’re right that I need the new reg/rect. So I guess I will try to contact Tony for that.

I’ll keep you posted on the results… Thanks again…Sam

[Geezer]

I try to offer to take feedback and critique to make it more frendly when I do get some. Actually the worst anybody has said is that one thing or another isn't clear. I then try to doctor it up a bit. I'd like to think of my FAQ page a resorce page for electrical problems on old bikes...

Geezer

[TopCatGr58]

Hey Sam,

Thanks for the background info. Not meaning to jump the gun when you haven't gotten your replacement Reg/Rect yet, but want to talk about your carb cleaning. These carbs are very finicky when they are dirty, gummed or varnished up! Just pulling the float bowls and spritzing around won't cut it! Did you disassemble the floats, pins, and remove the main and pilot jets, and remove the vacuum slides, and then the main nozzle down the middle of the carb body that the main jet screws into, remove the Pilot screws on the top front of the carbs, and the float needle seat, valve, and THEN soak all of these parts in carb cleaner, and also spray down into the pilot jet tower to ensure that you saw cleaner squirt out the front pilot screw opening, and then put your finger over that, and ensure that it squirted out the little hole on the inside of the carb throat below where the pilot screw fits? Don't forget to put the pilot jet tower plugs back in!Sorry for runon sentence/rant!

Okay, the compression values aren't too bad, but were they done with engine warm, all plugs out?

Had the bike sat a while....like a year or more...before you got it back? You said you had put WD40 in the cylinders, that could still be partly some residual there. Plus, if it wasn't running properly to begin with, could be lots of carbon build up in the cylinders? Could be a stuck ring, could be a leaky valve seal?

Until you get the charging circuit working, the tach won't work, and the bike can run rough due to not enough juice getting to the TCI. Also, the 78's are prone to the Pickup Coil wire failure, you'll want to investigate that will you're waiting for the Reg/Rect.

What kind of oil did you put in, hopefully not full synth?! Once you get it running and charging properly, it may just need some good highway miles to burn off excess carbon and such in the cylinders and from the pipes? If you didn't do a thorough cleaning of the carbs, you may want to pull them off again and go thru them again.
T.C.