battery disconnect switch

vmax02rider

Joined
Sep 2, 2008
Messages
87
Location
Mammoth Lakes, CA
has anyone ever installed a battery disconnect switch? every battery i've had (many) discharges within a week or two if left connected. it's a pain to disconnected from the battery terminal so i am thinking of installing a switch that can be operated without removing anything. going with my philosophy of making every move easily reversible, i am thinking to disconnect the negative wire where it connect to the frame and insert a wire with switch from that original wire to the frame. since there is a 65a main fuse and 30a ignition fuse in parallel , i am thinking a wire and switch rated for at least 95a will be needed. the switch would be accessible to the right of the battery. any comments or suggestions?

a quick search turned up this switch:

6-24 Volt Battery Disconnect
Single Pole battery disconnect w/removable key
Two Positions: Off-On
Rating: 6-24V DC;
1000 Amps Intermittent
@ 12 Volt for 10 seconds.
500 Amps Intermittent
@ 24 Volt for 10 seconds.
50 Amp Continuous
Terminals: two 10 mm Studs
Actuators: Removable key
 
Get your self a Deltran battery tender. Just plug it in and let it sit. It will keep your battery toped off ready to ride. With a cut off switch, you will have to reset your clock every time you switch it off. It might affect the engine computer as it draws a little bit of power over time.
 
one issue that doesn't solve is when i am traveling and leave the bike in a remote location for several days. i don't care about the clock. i imagine the computer will go to a default state.
 
I'd say something is either wrong with your charging system, or more likely, you have an abnormal drain going on somewhere to kill a battery that fast. That is not normal.
 
Any automotive or marine battery isolator switch will be up to the job. You would not need to add the fuse ratings together to determine the highest likely load. The higher one should be sufficient, and that is well within the current ratings I have seen for these types of switches. But investigation of the cause of this problem might be a better solution in the long run...

Ciao,
 
The problem with disconnecting the battery is that you will have to reset the bikes clock every time you do this. Another way to maybe get the battery to last a little longer would be to disconnect all the accessories you've added in case they are the cause of the drain. What I did was add a relay between my battery and the accessory fuse block I installed. With the key off there is no power going to the fuse block so no extra drain. Once the key is on the relay is powered and everything I've added has power. That being said I also keep the bike on a Battery Tender too when not being ridden for more than a few days.
 
If you have access to a AC outlet near where you park your bike a battery tender might be a solution. It seems like the battery is draining very fast so how old is it? My battery is 3 years old and seems to be more capable of maintaining a charge. I guess if there are a lot electric extras added it might good to check all that wiring to make sure there are no parasitic drains.

Gerhard
 
If a battery goes dead in a week something's not right. I'd check the bike no load (bike off) drain on the battery.
The 1300 spec is 2.5ma quiescent drain. (next to nothing)
Make sure all your acc stuff cell phone gps chargers etc. are dead when the bike is off. IOW a relay that disconnects your acc fuse block.

The clock and trip meter would reset but the ECU won't care with a disconnect.
 
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The only time I've ever had an issue with the battery draining below what will start the bike was a long time ago when I used to let the bike sit parked through the 3-4 months of winter. Otherwise the bike should be able to sit parked for a week or two at least and still have charge enough to start without issue. Since you state every battery you've had has this problem, I would say the problem is not the battery but something else on the bike. I agree with others here that there is a parasitic, or faulty drain on the battery that really shouldn't be there when the ignition is off. Any problem like that really should be fixed before considering a band aid approach to cope with it. You really need to find and fix the problem. The digital instrument memory bank (clock, trip meter, etc.) and maybe ECU are the only items that should be using the battery when the ignition is off, and that drain is so small it should take months to bring down the battery.
A battery maintainer is good peace of mind but should not be needed if you ride some distance every week or two.

I also use a relay to turn on/off all my farkles on the bike. The combination of the relay triggered by the Aux outputs and fuse block is called an isolated power setup (power comes directly from battery only and isolated from any/all factory circuits, and is shut off by the relay when the ignition is off). I never use bike factory wires that are being used on the bike to power any item I add. I've never had an electrical issue doing this.
 
Bush said:
I'd say something is either wrong with your charging system, or more likely, you have an abnormal drain going on somewhere to kill a battery that fast. That is not normal.
Click to expand...

^ This really says it all. You've got a leak Skipper- fixing that is the #1 order of business.

The quickest way is to separate the OEM from aftermarket loads. Test OEM side first, then aftermarket items one by one. You'll quickly find what's doing the harm.

Either way- draining/leaving in that state does enormous harm to batteries. A fully charged battery is a happy battery.
 
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Not on a motorcycle but I'm sure the procedure is the same.

[video=youtube_share;zdIKNnwEjIs]http://youtu.be/zdIKNnwEjIs[/video]
 
Excellent tutorial but I still don't think he found the actual problem.
Since the light switch was on, he should have/ would have seen the illuminated light .. since there was no light, the bulb was either burned out or missing . In that case there would be no current draw . But it probably did narrow down the problem to that particular circuit .
 
Pretty sure someone has posted a "how to" on ST-O already. I don't have time (or a large enough screen) to search for it now.
 
I will agree that you need to find the drain first. A properly wired ST, even with accessories, should not be killing a battery for at least a month or two.

And on a side note... adding together the fuses for the total draw will not give you the right amount of load. The starter wiring is not fused. The fuse for the solenoid is just for that. The power to the starter does not go through that 30 amp fuse.

I did measure current draw on my ST awhile back. On a warm day I was pulling about 125 amps. Colder weather and thicker oil will probably bump that to 175 or more.
 
This image shows you how to set up a parasitic battery drain test to measure the current draw (DC amps) on your battery.

Make sure you do it with everything on the bike turned off.

Parasitic Battery Drain Test.jpg
 
Establishing that you actually have a significant battery drain with the ignition off and how much is the place to start.

A battery tender is a good idea but you should isolate and eliminate any parasitic draw if appropriate.
 
by disconnecting a cigarette power outlet, the problem has been solved. when i get around to it, i will put a switch on the outlet, because it is useful.
 
vmax02rider said:
by disconnecting a cigarette power outlet, the problem has been solved. when i get around to it, i will put a switch on the outlet, because it is useful.
Click to expand...

What's connected to it? with nothing connected to the outlet you shouldn't have any draw from it. So, unplugging whatever is plugged in should also "solve" the problem.
 
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