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Old 01-01-2012, 04:00 PM   #1
ham_bone OP
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Oddometer: 7
Question Bike ('76 R75/6) Doesn't want to start after winter sleep.... Any ideas?

Hello all,

been lurking for a while and digging through posts on electrical, ignition, starter relays, coils, etc..., but i'm still lost. electrical issues confound me,.

So, I drove my beloved (1976 R75/6) into an unheated storage unit for the winter and abandoned her for deep sleep in the cold of Montana. That was last winter... now she lives with me in my garage, also unheated, but she won't start. I wonder if this is some sort of protest for the neglect she suffered.

After several failed attempts at starting her, a subtle plume of electrical smoke wafted up from beneath the gas tank. But, i can't find the source of any melted wires.

Here are the details:

She started with no issues a year ago. Was then left in cold storage.

I don't have a kick start.

Tank is full of fresh fuel.

Carbs are clean and in good shape with no gunk in the bowls.

Battery is strong and on a conditioner when not in use. (though i just noticed the voltage drops from 12 to 6 when I hit the ignition).

With key on, clutch lever pulled, and start switch depressed, the starter DOES turn the motor over.

Horn DOES NOT work now

right and left turn signals DO NOT work now.

brake lights DO NOT work now.

headlight DOES work in both high and low beam

neutral light DOES NOT light when in neutral

starter DOES NOT fire when bike is in neutral without clutch lever pulled.

Anyhow, if anybody has ideas or prior experience with such issues, I'd appreciate any advice. At this point I'm wondering the following (but I hate to jump to conclu$ion$).

Do I invest in a new starter relay?

Do I invest in a new battery?

Do I invest in a new coils?

Do I invest in new plugs?

Do I invest in a Dyna III ignition system?

Do I simply wait for the spring thaw to figure this out (It's 24 degrees out today).

Thank You,

ham_bone
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ham_bone screwed with this post 01-01-2012 at 07:33 PM
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Old 01-01-2012, 06:42 PM   #2
noman
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bimmer / bummer

the subtle smoke plume is worrisome, and the drop to 6v whilst attempting to start is also a clue, but ............ if it were me i'd:

make sure no rodents have nested in your air filter


clean both ends of the battery both leads (some of the stuff that used to work but do not now may be caused by a poor battery ground)

have the battery load tested at any car/bike shop

clean or replace the points, check static timing

clean or replace the plugs

check for nice, blue spark
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Old 01-01-2012, 07:28 PM   #3
ham_bone OP
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Definitely no rodents in the air filter. I checked that out earlier today. I'm wondering if the smoke was a coil burning our or something. I had been cranking and cranking and cranking the engine/starter for a while before that happened. It might have been the battery over heating. I have no idea.

Quote:
Originally Posted by noman View Post

check for nice, blue spark
thanks noman,

Okay, this will get some laughs, but i don't know how to check for a spark (I'm a noob)... I assume I just pull the plugs, and re-connect them to the plug wires, then hit the ignition? Is there anything more to it?

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Old 01-01-2012, 07:41 PM   #4
crazydrummerdude
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"It's always the battery."

...

Yeah, that's one way to check for spark. Just leave the plugs resting on the heads. You should see a blue/white spark.
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Old 01-02-2012, 10:44 AM   #5
Wirespokes
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It's the battery

The biggest problem - and most immediate - is the battery. Twelve volts is too low - that's 3/4 discharged. And dropping to six is definitely reason for concern.

First step is to charge the battery!

If it doesn't charge up, replace it!

You'll get nowhere troubleshooting with a bad battery - so there's your entrance point - ensure the battery is good!

To understand the situation you're running into - realize that trying to start a cold engine (in low temps) is about the roughest job a battery can face. The engine oil is thick and gives high resistance to the engine turning over. That means the starter has to work harder which equates to more current drawn from the battery.

At the same time the ignition system has to provide a strong spark to ignite the cold fuel that is more atomized than vaporized - not an easy task.

But there's not much electricity left over for the ignition since the starter is hogging it all. Just a slight drop in voltage causes a huge drop in spark power - that's the key factor here! With such a low battery, the engine isn't turning over fast enough, plus there will be such a weak spark the plugs will most likely be wet with unburnt fuel and unable to cut through the dampness.

So the first step is to get the battery up to 12.7 Volts, and ensure it doesn't drop below nine or ten while cranking.

Another trick is to only hit the starter for short bursts. The longer the burst, the more the battery runs down. Many short bursts are better than one long one. The only time cranking the engine for a long burst is necessary is when it's flooded.
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Old 01-03-2012, 02:06 PM   #6
ham_bone OP
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thanks for all the feedback folks.

i'm thinking it's just too cold out to trouble shoot this. i'm thinking i'll wait until spring. for one, the bike is struggling and for two, i can only work a little while before i'm swearing at my freezing fingers.

however, today i connected the bike to my truck via jumper cables to look for a strong spark. there is a spark, but it's not too strong. and, i discovered the source of the smoke. in the photo below, you can see at the circled connection, this is the spot that is over heating and smoking. this is a replacement valeo starter. i wonder if the cold temps simply have it under too much stress...?
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Old 01-03-2012, 03:24 PM   #7
noman
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puffy

"I had been cranking and cranking and cranking the engine/starter for a while"

starter and connections will overheat if the above actions are followed (connections especially if they are loose or corroded). take it easy on the ol' girl, and she'll treat you fine.
bobp
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