If your trying to clean up the look of your custom BMW Boxer build here is a great way to mount the battery and get it out of the way!
 
CNC made for a precision fit
Welded corners
Positive battery cable included
Stainless steel mounting hardware
Made to work with a standard R65 or /5 battery (19ah or 12V20P) which is more than enough for an R100.
Dimensions: 7" x 3" x 6.5" inches
Comes with factory BMW battery straps
Does not clear the stock center stand, rear exhaust cross over on 81-84 models or pre silencer on 85-95 models.
Plenty of room for an Anti Gravity 8 cell battery. You will need to surround it in foam rubber.
 
We can supply you a battery if needed.
 
NOTE: Not pictured battery cable & battery straps