GS history... or, M/C trivia....

[GregM.]

Can any of you old-timers (I am one, so I know) take a few minutes to educate me on 6 volt vs. 12 volt systems. I don't mean technical - like how they work (that's beyond me), I mean M/C history as in when and why the change.

1- Back in the 70's didn't most all common m/c's have 6 volt batteries and electrical systems... even the bigger bikes?

2- Do all GS's have 6 volt systems, or, are there some later big touring models that have 12 volt systems?

3- Today, don't all common m/c's have 12 volt systems?

4- Over what period of time, did this transition take place... and why did they all eventually switch?

I don't want to change anything about mine at all... I really just want to know the history regarding this. Thanks a ton for your time... I'm really enjoying getting back into it

[Redman]

Motorcycles have had 12volt for as long as I have known (early 80s) and most cars were 12volts for as long as I have known (late 60s). I think some older VWs (like 50s) were 6 volts and some older (like 50s) tractors ectera were 6 volts.

For motorcycles; most bikes didnt have starter motors till late 60s or early 70s. That would be one reason for going to 12volts instead of 6.

For cars; I think as engines got bigger and higher compresssion then more power was needed for the starter motor.

[Tom MLC]

Every bike I've ever owned has been 12V, going back to 1978. I know earlier bikes had only 6V. Most motorcycles back then didn't have many electrical devices either. Starters like Redman said, plus gobs of sensors, lights and electronics would put a huge demand on a 6V system.

[Big T]

Most street bikes have been 12v since the mid 60s. A few European bikes, Like my 1970 Ducati 450, are 6v because their design dates back to the 1950s.

Dirt bikes and enduros still were 6v up into the 80s

Suzuki GSs were always 12V

[rphillips]

Yeah, most everything changed to 12 volt in the mid to late 50's. I remember I had an "1952" Ford truck that was 6 volt, as well as a "1946" International Model " "A tractor. 12 volt meant more electrical power, much like a 9 volt rechargable drill as compaired to an 18 volt. My question always was why did many old vehicles have a positive ground system? Sounds strange these days, but the pos side went to ground, and neg. went to the electrical components.

[GregM.]

Thanks !!

Duhhhh....... Sorry, a stupid question - I just lost my mind there for a while as I get back into thinking about m/c mechanics and maintenace etc.

I did have a dirt bike in the 70's that was 6 volt... in the 80's I had a 1965 Porsche 356 that I enjoyed drivin' around and fiddlin' with, and it was 6 volt... and I have a battery charger that you can switch between 6 and 12 volt. Anyway, I just had a brain fade thinking about old vs. new m/c and how they've changed etc.

OK back to reality... Thanks

[bwringer]

The small bikes and scooters that got Honda started in the US in the 60s were usually 6 volt, and some small scooters still use 6 volt systems. There were other isolated exceptions.

12 volts (with negative ground) became an automotive standard sometime in the 50s as others describe. There's nothing intrinisically wrong with 6 volt systems -- you can make a starter or battery that's just as powerful either way. However, 6 volt systems often require heavier wiring, coils, etc.

[Clone]

VWs switched from 6 to 12 volt in 67. I had a 66 which was the last year for 6 volt and I converted everything to 12 volt except for the starter. Just touched the key and it was running even at -35 degrees Celcius. 6 volt systems were a little more durable and simple because things were simple when they were used, and I believe 6 volt starters were more torquie at the time than 12, but don't quote me on that. Most of our pre-70 tractors were 6 volt unless they had two 12 volt batteries connected together.

[txironhead]

I got a crash-course in vehicle electrical systems with my very first car. When I turned 16, I wanted a "classic", so I took my whopping $2,000 I'd saved and bought a baby-blue-and-white 1956 Chevrolet 210 Sedan. 265V8, powerglide auto (2-spd), no power ANYTHING. But MAN was she beautiful!

The starter went out shortly after I bought the car. Since places like Autozone didn't carry 35 year old starters (this was '91), I ordered a rebuild kit from a specialty shop and rebuilt it myself. It was when I went to reinstall the starter that I discovered something odd: the car had a positive ground! My dad told me some old cars had this so out came the huge, hardback Chilton's manual. Nope. Negative ground. One of the PO's (I was the 7th owner, geez) had switched it to positive ground. Well, THAT explained why the radio never worked. Took me a while to redo all of his "mods". The radio was fried beyond reasonable repair, so I threw a boombox with a 12v adapter plugged into the cig lighter and called it a day. Damn I still miss that car......

[mixongw]

The main reason they switched to 12V from 6V was "size". In order to deliver the same amount of power, the 6V components (wire, starter motor, etc.) had to be twice the size of the 12V system. It takes twice as much copper with a 6V system to conduct the same power as the 12V system. There's been talk in the automotive engineering departments of going to 24V systems to save weight.

[bwringer]

The main reason they switched to 12V from 6V was "size". In order to deliver the same amount of power, the 6V components (wire, starter motor, etc.) had to be twice the size of the 12V system. It takes twice as much copper with a 6V system to conduct the same power as the 12V system. There's been talk in the automotive engineering departments of going to 24V systems to save weight.

Many aircraft and military vehicles use 24V systems for that reason.

[koolaid_kid]

For cars, I can speak to Ford:
1954 was 6 volt.
1955 was 8 volt.
1956 on was 12 volt.
For bikes, I can speak to Honda:
My 1964 150 Benly was 6 volt.
The 1965 160 was 12 volt.

[rphillips]

Thanks Koolail kid, were any of them positive ground? My "52" Ford truck was, BUT WHY A POSITIVE GROUND??????

[Redman]

Positive ground: No particular advantage to positive verses negitive ground, that I know of. Just that some folks did it one way and others did it the other. I say its like driving on left verses driving on right, just that different areas/people did it one way and others did it the other way.

I had Sunbeam (early 60s) that had positive ground. Had to argue and argue with my girlfriend's brother when we were gonna jump start it. He was saying the negitive IS ground and ground IS negitive, as if the metal in the cars frame could not conduct current in that direction. To resolve the issue we push started it. This incident has long served me as an expample of how just knowing facts is helpfull but often times really need to understand the situation better.

[Redman]

I have read some automotive industry trade publications that talked about cars going to 24 volts, like Brain said. One reason was to operate the A/C compressor with electric motor so it could be variable speed and so it didnt need to be in engine compartment driven by a belt from the engine. Other apllication for the 24 volts was to operate the intake and exhaust valves to allow variable timing.

And as stated before, in general, the idea of higher voltage is so can get more force-power-watts with less current, meaning smaller wires.