Replacement Batteries

[Kiwingenuity]

Just a quick message to everyone out there with a GS500F...

After purchasing a 2007 model GS500F with less than 1000 miles on it I noticed the battery was in need of replacement.  I decided to go for an AGM sealed type – 20% more cranking current and no maintenance.  This was in the form of a Motobat MB10U (the type recommended by Motobat for the GS500).

Motobat batteries are normally great batteries – unfortunately the clever adapter posts that screw onto the battery terminals to allow the bike wiring harness to attach raise the height of the battery connections by about 10mm (1/2").

Less than two days after replacing the battery I pulled up into the driveway and the bike died – completely – no ignition lights, nothing. After commencing a bump start, the bike ran very rough on idle, and had no power.  Increasing the revs resulted in the lights getting dimmer and the bike died. Obviously no battery in the system..

Since I had no ignition power, I decided to do some ferreting around for the master fuse, and finding no issues there, I noticed something I didn't expect...

When you pop the seat back on, the result is the Motobat battery is forced backwards so the +ve terminal connector will pinch the silicone terminal boot cover directly against the frame that holds the rear brake fluid reservoir – Net result – bad things happen when a hole is eventually worn through the silicone rubber boot that covers the terminal, and a short to the frame results in the battery destroying itself internally.

Probably was lucky the heat didn't melt a hole in the reservoir....

My fix has been pop a high density foam spacer to ensure the battery is kept forward and whittle the supplied hex head cap screws down by 5mm to allow the battery to not require the adapter posts.

Hopefully MotoBat put out a notice or supply some spacers with the pack - they were kind enough to replace my battery at least...

[adidasguy]

Sounds like the wrong battery.
The seat does not touch the battery.
Friend had same situation: wrong battery! It was too high. Put in correct battery and everything fit OK.

It is an odd problem since the battery LOOKS like it would fit.

How about pictures showing your problem?

[codajastal]

I have that brand of battery with the lugs and my seat does not come close?
Photos of battery/seat?

[oneNonlyTu]

I have that battery, albeit in a 91. Did you use the correct post? I think there's a right way and wrong way to put them in. Also mine came with an "adapter" which was just a stupid piece of plastic underneath that raise the whole battery (by 9mm IIRC) to be compatible with another similar battery size. Make sure you take it off!

[codajastal]

I have that battery, albeit in a 91. Did you use the correct post? I think there's a right way and wrong way to put them in. Also mine came with an "adapter" which was just a stupid piece of plastic underneath that raise the whole battery (by 9mm IIRC) to be compatible with another similar battery size. Make sure you take it off!

Come to think of it I think mine came with that too and yes you need to remove it.

[Kiwingenuity]

Me again,

No photos sorry - the dealer took some to send to Motobat - they didnt believe me to start with either..

I took the battery out again at the weekend- noticed a 10mm thick piece of foam under the battery - I may consult the great book of Haynes and see if they added the piece of foam for a smaller factory fitted battery.  At any rate if you throw away the spacer that comes with the Motobat battery and have a small piece of 3mm foam under the battery the Motobat fittings will work fine...

[k.rollin]

I use a Motobatt MB10-U battery in my '04 GS500, and I've had zero issues with it for the last year or so. There was a removable plastic plate that I had to take off in order to make the seat go on properly though.

[oneNonlyTu]

Battery should be sitting in just the battery tray, nothing else. Both the '91 and the '07 I have (mine and wifey's) nothing under battery except the tray. So that foam's your problem definitely.

[knowles]

In the 89 that i have it had a little piece of foam but only about a 1/8" think.

[The Buddha]

That es12bs sideways trick I posted like 12 years ago had a caveat I posted 8 years ago - the battery will rock under hard acceleration to ground the +ve to the brake reservoir bracket.
And yes we put something in between to stop it. Rubber or plastic ...
Cool.
Srinath.