Jump Start & Charge from a Portable 12v Battery?

1. store my R1100S in an underground garage with no electricity and try to ride once a month in the winter.
2. keep a portable 12v battery with both clips and a cigarette lighter cord that fits into the accessory socket I had installed when I purchased the bike (Clips useless on this bike because battery is buried way inside bike).
3. do NOT want to fry the electrics on this bike that has reliably carried me 50,000 miles since purchase, and closest dealer is an hour away.
Q1. if battery looses enough juice so bike won't start, may I jump it from the portable, through the accessory receptacle with damaging bike?
Q2. Will leaving the portable plugged into bike for a few hours a week help charge the battery?
Q3. What is the approx. life of a stock BMW battery for this bike (on second one, first lasted 3 years).

118902 said:

Q1. if battery looses enough juice so bike won't start, may I jump it from the portable, through the accessory receptacle with damaging bike?
No, That circuit is fused with a 7Amp fuse and it will blow if you attempt to jump start the bike using that circuit.
Q2. Will leaving the portable plugged into bike for a few hours a week help charge the battery?Possibly but only if that 'spare' battery is fully charged and you do NOT attempt to start the engine while it's connected. The two batteries will equalize.
Q3. What is the approx. life of a stock BMW battery for this bike (on second one, first lasted 3 years)
One to three years is all I've ever got from a BMW battery. I would not buy another. .

Click to expand...

Mick

I got 5 yrs out of my last BMW Gel Battery. I replaced it last month with an Odyssey PC680.

Thank you !!!

Like Mick said, don't try to start it with power on the accessory outlet.

Here's a charging option though.
Best if your car is parked beside the bike but would also work with the portable battery if it's big enough.

Car battery >>> 100W inverter >>> Battery tender >>> Accessory outlet

Leave it on overnight every other week.

As a bonus, it might point out a deficiency in your car battery.

The safest place to jump start it is at the starter+ terminal and the starter body mounting bolt- with suitable sized alligator clips. Be extra careful.

GSAddict said:

The safest place to jump start it is at the starter+ terminal and the starter body mounting bolt- with suitable sized alligator clips. Be extra careful.

Click to expand...

Yup, I have done it that way several times. Easy access on the GS. On the RT you can do it pulling the seat and using a screwdriver to reach the positive post.

Best way is to get the jump start post adapter and add it to your starter cover.

Jim

JimVonBaden1 said:

Yup, I have done it that way several times. Easy access on the GS. On the RT you can do it pulling the seat and using a screwdriver to reach the positive post.

Best way is to get the jump start post adapter and add it to your starter cover.

Jim

Click to expand...

For those willing to spend the $ & time - you bet!