Will bike run without battery?

[davewallen]

I finally got my r/r installed..(&^*&*#!!!) I went to measure the voltage, and got 18.5. Smart me, I measure straight from the r/r, and get 14.5. So, I guess I go get a new battery tomorrow.

But for giggles, I started the bike and tried disconnecting the battery. Instant death.

Shouldn't the bike generate enough to keep itself running without the battery?

(81GS850)

[marvinsc]

No electrician and only a half @ss Mechanic Here, but to My Knowledge NO, the bike will not Run without a Battery installed.

[SkeletonLake]

Theoretically yes although you run the risk of burning out the regulator without a battery as the system will still be putting out enough juice in trying to charge the battery.

[davewallen]

Thanks. Went and got my new battery. Now to give it a day and see if everything is working ;-)

[argonsagas]

Yes, the bike should run without a battery installed, subject to the number of RPMs involved as there must be enough engine speed to turn the stator fast enough to generate the power needed by the ignition system as well as any lights that are ON.

Doing this for any extended time is not a great idea.

On the other side, the bike will run without the charging system connected, and if the R/R totally fails you can disconnect it and still drive the bike on battery power alone.


Regarding the numbers mentioned:

The stator puts out well above 18.5 volts, but you only see those numbers if you check the leads going into the R/R from the stator.

If you are finding that voltage anywhere else, at any time, you are guaranteed to have a short-life battery, and other components will also fail prematurely.


14.5 volts is the maximum acceptable output from the R/R, but if you have the standard complement of electrical items for your bike, and th ebattery is freshly-charged, this voltage indicates poor connectors somewhere, and increased draw due to corrosion/dirt, etc., or it means you have a poor R/R, as 14.5 volts should not be constant and will boil the battery dry, AKA fry it.

[salty_monk]

I thought the battery on a GS was part of the system, they won't run without. Those that do have some kind of capacitor in them I believe....

[davewallen]

Regarding the numbers mentioned:

The stator puts out well above 18.5 volts, but you only see those numbers if you check the leads going into the R/R from the stator.

If you are finding that voltage anywhere else, at any time, you are guaranteed to have a short-life battery, and other components will also fail prematurely.


14.5 volts is the maximum acceptable output from the R/R, but if you have the standard complement of electrical items for your bike, and th ebattery is freshly-charged, this voltage indicates poor connectors somewhere, and increased draw due to corrosion/dirt, etc., or it means you have a poor R/R, as 14.5 volts should not be constant and will boil the battery dry, AKA fry it.

Yup. I had 18.5 from the battery. Even when it was disconnected. They gave me a warranty replacement, though. Sure did seem like an odd number - enough to make me check my VOM on a another source.

[jbs80106]

Not my 82 650G...

battery drained too low or disconnected and the bike dies. Otherwise, I'd not have gotten stuck on the side of the road with a crapped out charging system when the battery ran down. MAYBE if I disconnected the headlight/tail-lights, but I seriously doubt it.

I think there's large capacitor on bikes that don't have electronic starters (you know, the ones you have to kick start) to keep the engine firing. The GS bikes don't have it.

Sorry.

[davewallen]

After some thinking, I've figured that a bike SHOULD be able to run on the charging system without a battery.

After all, the battery is supposed to be only for starting.

Anytime the bike is running, the charging system should be supplying enough power to run everything and STILL have a little left to recharge the battery. If it doesn't supply enough to run the bike, then you're always pulling from the battery, and sooner or later you're dead.


Haven't tried with my new RR yet.

[ironb12s]

Uh, folks, with the battery out, where is the electrical earth ground? That would explain why it won't run without the battery. :-|

As an aside, I've tried to put this off until we've had time for an adequate shake-down, but we over at Riders Of Vision had a spate of stator and R/R failures recently, so we are in the process of designing a new 'BUCK' regulator, one that charges the battery until full, then switches off the power coming from the stator rather than shunting it to ground. Any of you interested in trying one as, possibly, a Beta tester? It's being done in CO. And if someone has the basic wiring diagram that is common to the GS models, we can incorporate that into the design. The old Suzuki's and Yamaha's charging systems were much the same...

I'll be getting one for both my GS750 and my Vision. If noone here tries it themselves, I'll provide a report...

[davewallen]

Uh, folks, with the battery out, where is the electrical earth ground? That would explain why it won't run without the battery. :-|

As an aside, I've tried to put this off until we've had time for an adequate shake-down, but we over at Riders Of Vision had a spate of stator and R/R failures recently, so we are in the process of designing a new 'BUCK' regulator, one that charges the battery until full, then switches off the power coming from the stator rather than shunting it to ground. Any of you interested in trying one as, possibly, a Beta tester? It's being done in CO. And if someone has the basic wiring diagram that is common to the GS models, we can incorporate that into the design. The old Suzuki's and Yamaha's charging systems were much the same...

I'll be getting one for both my GS750 and my Vision. If noone here tries it themselves, I'll provide a report...

I ground my r/r right to the neg terminal of the battery, so that should take care of the ground problem.

As fare as shutting down the stator when the battery is charged, what kind of threshold are you setting it at? Theoretically, the moment you shut down the output from the R/R, you are running off the battery, so therefore in 1/100 of a second, the battery is no longer fully charged, and you need to start charging again. All that switching off and on is going to generate heat, although I don't know if it would compare to the heat generated by soaking up the excess like a nornmal R/R.


I was looking at your yamaha site, and notice they have a relocation recommendation. Rather than that, (on GS) I'm thinking about mounting a computer CPU cooler on my R/R. Pretty sure they are 12V. Enough heat sink grease to form a solid heat transfer base, and I should be ok.

There a mention here that if you really want to eliminate heat from your stator, you should really try to load your bike with enough lights to fully use all the power generated: (they also explain why you should never jump your bike from a running car: while the car's 1400 watt generator/regulation is trying to keep the voltage at 14.5, the regulator on the bike is trying to use all the energy not required by generating heat , and a 1400 watt generator will win the battle every time)

http://tinyurl.com/24a6kv

[Casino Joe]

I was looking at your yamaha site, and notice they have a relocation recommendation. Rather than that, (on GS) I'm thinking about mounting a computer CPU cooler on my R/R. Pretty sure they are 12V. Enough heat sink grease to form a solid heat transfer base, and I should be ok.

Excessive heat sink grease will actually create a barrier against effective heat transfer. A super thin layer to fill any voids between the heat sink and core is all that is required. More is not better.
Ask me how I know. 8-[

[davewallen]

Excessive heat sink grease will actually create a barrier against effective heat transfer. A super thin layer to fill any voids between the heat sink and core is all that is required. More is not better.
Ask me how I know. 8-[

I think I'll guess. But thanks for the advice - I wouldn't have known that without learning it from an experienced pro.

Like Rodin said: "Nothing is a waste of time if you use the experience wisely."

Of course, he didn't have to replace a $100 r/r, did he? (or was it a $200 CPU?) ](*,)

[Casino Joe]

$100 ??? :shock:

I just scored a Honda CBR1000 5 wire R/R on fleabay for $30 shipped.
Check it out, you can get deals like that quite often.
If you cant find any, contact duaneage (a GSR forum member) as he often has Honda 6 wire (sense wire) R/Rs already modded with the proper terminals for our bikes for sale for around $40.


And yes, it was a $200 CPU.

[TheRedlineMan]

A high speed switching regulator based on something like a PIC chip would work better. It will allow the system to 'trickle' charge the battery to keep it up to full power. It'll also handle surges from the Stator better, and can be set to prevent surges due to electrical shorts etc.

Well that's how I'm looking at doing it.