Not a 914 question (could be) but actually Sportster question. Been having some electrical issues, and these things are so damn amp critical with the computer that almost anything that causes less than ideal conditions causes all kinds of electrical mayhem. Anyway, cutting to the chase, what would cause my negative terminal on my battery to half freakin' melt?!?! The insulation on both my ground strap and my + strap are compromised...I'm assuming one of them was hitting the frame and caused this. Educate me please.

Well, to melt a ground strap, something large. Shorted starter or shorted cable. Usually IMO when it's just the ground and not the + it's a bad ground connection. And black wire tends to go bad quicker "black wire death". Something with the dye reacting to copper turning it green or black.

Didn't melt the strap...melted about half of the actual negative terminal on the battery itself.

Never seen that one. I would think the terminal would have had to been arcing to do that.

And what, pray tell, would cause the terminal to arc ?

Only dirty or loose that I know of. And I forgot..

Melted the terminal? Wow! Got some pics?

Very high currents can cause damage to wires. In general, any battery can supply currents that rival and exceed welding units. Short a battery's + and - terminal together and you can have massive currents such that the battery could be damaged.

So was this damage new or has it been like that for a while?

Assume someone is working on their starter w/o disconnecting the battery. If the starter wire is accidentally touched to ground, high currents can occur and cause major damage to wires.

The basic electrical formula involves voltage V in volts, resistance R in ohms, and current I in amperes. They are related by:

V = I x R

rearranged:

I = V/R

or:

R = V/I

In the case of someone shorting the starter wire to ground, assume the wire resistance R = 0.05 ohms. Then the resultant current is:

I = V/R = 12V/0.05 = 240 amperes

Another basic electrical formula for power W in watts:

P = V x I

In this case,

P = V x I = 12V x 240 amperes = 2880 watts

This is enough to do some extreme welding or burn and melt wires.

Brand new damage...just happened. Like I said, I was cranking it, and it wasn't responding, until I pushed on either the wires connected to the (+) terminal or actually "thumped" (with my fist) on the side of the battery itself.

Click to view attachment

Sounds like a dead short on the positive cable causing eccessive current on the cables. If the ground cable was loose or corroded, more heat would concentrate on that cable. Copper is a great heat conductor, lead-alloy terminals have a low menting point. I would also assume your battery is no good at this point. Could be a short inside the battery as well. is there any signs of arcing near the battery cables?

Based on your picture, it looks like poor connection/loose terminal. The minute gap between the battery and cable would have a plasma arc during cranking. This arc would consume most of the current, preventing your starter from working while melting the terminal.

No signs of arcing that I can see. The battery is still showing 12+ volts. Does that mean she's OK?

Here's the recent history. She's "stutter" for a nano second before firing up...almost act like a dead battery for the split second and then fire up. She's want to stall for the first few minutes too...until she was warm. I thought it was a cold start issue with nthe computer needing a reflash. Anyway, on Saturday she wouldn't start or even light up her dash lights. I roll started her in second and rode her home. After I shut her off, she restarted with no problem...more than a few times. I now realize that the battery wasn't dead...there was a short somewhere. With the battery cover off, she'd either click once and die, or click repeatedly (solenoid), until I'd press on the three red wires attached to the positive battery terminal, or smack the side of the battery a little...then she'd fire. While I was doing this tonight...trying to see where the short was, she started to smoke. Once I pulled the batter out, I saw what had been smoking.

Oh yeah...2007 Sportster.

I had just cleaned and tightened the cables. Can't believe it was a loose connection. Could it be a bad cable itself, or a short in the battery itself? One of the guys at the HD dealer (a parts guy...not a wrench) said something to the effect that the plates are pretty much welded (or something) and that it would be very unlikely that the battery could have a short.

I would replace both positive and negative cables. Once that is done, charge the battery. Then turn the headlight on for 15 minutes. This will pre load the battery. Turn the lights off and try to start the bike. If it will not start, replace the battery. Make sure you pull and wiggle both cable connections WITH FORCE after they seem tight. You can also take the battery to a Motorcycle dealer and have it load tested. Do not use a CAR load tester as this can dammage the battery.

I'm thinking it is a problem with the battery itself. Something about the + post....

It takes a lot of volts to jump a gap. It takes amps to melt stuff. I vote for a short. It could be as simple as the positive cable on the starter has a bunch of crud on the connection that lets it leak to ground. Make sure thats all clean.

Will do.

OK, here's what I'm thinking given this information. You have a bad connection on the negative terminal such that all the current is flowing through a very small portion of your terminal. This could cause local heating and melting without massive currents.

Think about this: what if you put a small section of very small gauge wire like 20 ga in series with your starter. When you go to start it, the large current will smoke the wire in a millisecond.

I thought you said both terminals were affected?

I doubt a short somewhere as you may see that area arcing too.

BTW, you can get sparking and arcing with very little voltage. Keep in mind that a MIG or stick welder are actually "arc" welders and use very low voltages to product the arc. This is how you can get 125 amps or so from 125 VAC circuits with 20 amp circuit breakers.

I've seen this on a battery when the battery post itself has be twisted left or right, causing the strap on the inside of the battery to twist and partially shear, reducing the cross sectional area of the strap ( and hence its current carrying ability) and causing a hot spot.
What ever the cause, I would replace the battery and not take any cahnces, keep it as a jump start spare.

Neil & Jerry,

Thanks...yeah, no need to go cheap and get stranded. I'm replacing the battery and both cables today. If that doesn't fix it Ill just throw a match on it and call Flo.

Don't throw a match on it. I'll come over and haul it away for ya.

Because I'm just that kinda guy.

You duh man! It's the olive green one that's plucking my nerves. Take it and leave the black one.
Click to view attachment

Well, the local HD Stealer didn't have the cables, so I just took the new battery and usd the old cables (ordered new one s anyway...be here in a week). She seems fine now...the battery must have had an internal short.

Just a thought.....

Have you been welding on this car with the battery connected?


Or did I miss something in this thread? You can destroy a battery be doing that.

Yeah...I'd say you missed something.

Ok....Ken....sorry just waking up this morning out here....sunny weather here.

Maybe I'll just take my car out for a DRIVE!

Read your posts now. I get it. Nice work on your car BTW.

Thanks...hope to be driving after this weekend, but it's supposed to freakin' snow tomorrow...it's still Fall and I'm south of the Mason Dixon line!

You have the weight of the powertrain on the driving wheels. I think your traction will be Just Fine in the snow.

In my ongoing quest to rid this car of rust, I'm not about to drive her in the snow, which combined with the salt they use on the roads here, is responsible for the death of 99% of all the 914s ever to hit the roads around here. Snow? Suzuki SX4..."priced like a shitbox...not a shitbox" Esquire Magazine.

That is just a loose connection at the negative terminal. When it stuttered it was loose when you got it started it momentarily welded a small area to get going then came loose again and the loose connection started arching and melting lead, When it didn't start would have been the time to find it. The smaller surface area makes it more critical to keep a good contact between the cable and the post. If you tighten it and it has enough surface area left it will be ok but if the cable really heated up a lot it will not carry amps like it should.

The bs about a 20 amp circuit carrying 120 amps at 120 vac is not correct. Yes you might touch a wire connected to a 20 amp breaker but it would never carry 120 amps through a 20amp breaker for even two seconds. Also a starter wire is way smaller than a battery cable and it will smoke way before a battery cable will. Normal living room wall circuits are 15-20 amp 12vac circuits, if you were to try just touching two stranded lamp cord wires together just a flick and it will trip the breaker. If you don't know about electricity just take my word for it don't do it.

The terminal at the battery was loose and arched and got really hot.

Close...not a loose connection at the terminal...a "loose connection" somewhere below that...in the battery. A short inside the battery itself somehow.
KK

Cool bike.

how much?

Rich

Too late...gave it to Ken as discussed above.

The lead terminal and the cable will take anything the battery can put out. A loose connection inside the battery will only make the battery open up and put out nothing. The cable was loose at the battery, thats the only way that spot would melt from heat and being loose and arcing. The heated terminal may have opened up inside the battery after it was run and the alt added it's amperage trying to keep the bike running.

I'll concede because almost anybody knows more about electrical shit than I do.

Isn't a sportster a girls bike anyhow?

Kiss my a..ass..vagina!

Just messing with ya. At least you still have one. I sold my HD last year. The long winters up here damn near killed me. I sold it to a guy more patient than me.

Softtail Deluxe. A much better bike for a girl than a Sportster. It's lower, the CG is lower, it's not top heavy like a Sporty and much less off the line. People call Sportsters "Girl" bikes, or "Entry level" bikes because they are the cheapest. Some assholes will buy their SO a Sportster for her first bike because it's the cheapest HD out there. It is definitely not a beginner's bike regardless of gender. It's the quickest air cooled HD made and top heavy. I'd buy my "girl" a Dyna Low Rider or a Softtail Deluxe...really. Sportsters are the only HD that's consistently won races...from drag to flat track.

That being said, I know you were only effin' with me...love you man!

Also, bought a Street Glide in '06 and quickly sold it. Too sloth like.

Sportsters are air cooled, small, nimble...hmmmmmmmm, sound familiar?

Sportster is to 914, as Softtail Deluxe is to Chevy Cavalier!

I loves me an Iron 883. No frills, no chrome, just a lightweight bike.

Nah...my Nightster is the same bike, but a 1200 instead of an 883, and even lighter still!
Click to view attachment

And I replaced the mufflers with Rinehart black slip ons, and HD black "bullet hole" heat shields...the less chrome the better, and best sou ding pipes out there IMNSHO.

I like the lace wheels... your cylinder heads are too bright though.

You mean the rocker covers I agree. The Iron 883's inner rocker covers are the same as mine...the outer covers are easily swapped out with the black ones. I also like the Iron 883's blackened out block better too, but that's too much trouble to have powder coated, or I would.

Hey...are you smart enough to figure out why the same bike with a 1200 is lighter than an 883?

Ummm, because the 1200 displaces more volume and air is light?

In other words, no.

You basically have it...the 883 and 1200 use the same cylinders. The 1200 has a bigger bore...less metal...more air! The 1200 weighs a few pounds less than the 883.

SRSLY?

That can't account for more than a few pounds at best... I was joking in my reply because I hadn't a clue.

And yet you basically nailed it. Pretty sure it's under 2lbs. Still, it's funny when somebody says they are goiung for the 883 instead of the 1200 because they're new to riding, or smaller and want a lighter bike. When you tell them an 883 is heavier they're amazed.

Yes and the 883 runs about like a 72 350 honda, it has about 45 hp versis the 1200 with about 60-70hp. I think the buel 1200 is about 100hp though.

HP sucks...torque rocks. My Nightster with a mere Stage 1 upgrade (intake and exhaust) does 0-60 in 4 seconds and the quarter in high 13s...all this old man needs. There are old riders and bold riders...not both. Been riding for 40 years...no Hayabusa for me!