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R100RT battery

n1hnr941

New member
I apologize in advance for my ignorance if I am wrong but I think BMW way back when, blew it when they designed the battery installation on my 1983 R100RT. I had to remove the air box to get the battery out. It wouldn't go aft or to the side only forward:banghead . Duh.... Any of you airheads out there find a smaller battery that fits or a mod to do or is that the way it is? Good thing I don't foresee taking it out much. It had to come out this time to clean the battery box up. It was all rusty a looked like poopy. And anyone know of a good acid proof paint? I know there is some in the aviation industry but at $200 hundred a quart. I suppose if I replaced the battery with a sealed one then the paint is mute point. Anybodys thoughts?:bikes
 
The Battery tray will tile to the rear but you have to remove two small nuts on the side. The rear brake master cylender fits on one of the bolts.
 
Thats strange because there are two fasteners on the bottom of the tray under the battery that have to be removed before the tray will go anywhere. Maybe mine is a different year from your's.:dunno
 
Regardless of how it's done, AFAIK there is no easy way to remove the full size battery and /or the tray. BMW engineers sometimes spent too long a lunch hour at the bier stube!
I used a 19 AH hour M/C battery I got at Wal Mart. It slid right in and so far, so good.
I also have a Voltage regulator from Motorrad Elektrik which charges at 14.2 volts, so that helps.
 
Thats strange because there are two fasteners on the bottom of the tray under the battery that have to be removed before the tray will go anywhere. Maybe mine is a different year from your's.:dunno

The bottom bolts are rubber mounted and there's enough flex to allow batt box to tilt back enough for battery removal.
 
I apologize in advance for my ignorance if I am wrong but I think BMW way back when, blew it when they designed the battery installation on my 1983 R100RT. I had to remove the air box to get the battery out. It wouldn't go aft or to the side only forward:banghead . Duh.... Any of you airheads out there find a smaller battery that fits or a mod to do or is that the way it is? Good thing I don't foresee taking it out much. It had to come out this time to clean the battery box up. It was all rusty a looked like poopy. And anyone know of a good acid proof paint? I know there is some in the aviation industry but at $200 hundred a quart. I suppose if I replaced the battery with a sealed one then the paint is mute point. Anybodys thoughts?:bikes


A Wesco AGM battery is a nice fit. Drops right in and is 30AH.
 
Yeah, the manual for my '82 R100RT tells me to tilt the battery forward and slide it up - yeah right! I've always had to unscrew the bolts and juggle the tray almost completely off the bike in order to get the stupid thing out. I'd love to hear if there is a simpler way.

Balder
 
I have a 1984 R100RT and I have taken off the 2 bolts in the back. This allows the top of the tray to tip enough that I have put in and taken out both sealed and unsealed (mostly Yuasa's). It is tight, and I have had to watch the wiring harness
to make sure if it was out of the way, but that is all I have had to do.
 
I tried tilting it forward but the base of the terminals were too close to the frame. If I went any further I would shorted the terminals on the frame. And besides it wouldn't get by the air box anyway. Guess I'll look for smaller battery.
 
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I have recently replaced the batteries in my 91 & 95 R100RT with the Panasonic model LC-X1228P. These are a sealed 400 CCA. They have notches in the top that lets you use your finger tips to easily lift them in and out.
Did not even have to tip the battery box back to remove and reinstall these batteries. The battery box is not quite filled with battery. They are $98.00 delivered.
Hope this helps.

Ray
 
Working on my own, I discovered, in order, that the two bolts in the way for the seat frame need to be removed (easy) and that the battery tray can be unscrewed (also easy) and tilted backward to remove and install the battery. I have the stock-size Yuasa in my RS, which I think is identical in that area to your RT.

If you think this is difficult, try removing and installing the battery on a Honda VT600 Shadow. :huh If you can pass that test, rebuild the carbs ... :banghead
 
Well I put my battery back in and now I see the light Grasshopper! It was still snug and hung up on the tie down bolts but it worked. The corners of the battery still hit on the frame but a little nudge and down it went. Thanks everyone for enlightening me and get my Karma back in place:p
 
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