Ah, 12v. My memory dims.
If the battery only gets up to 11.xx volts after being on the charger (several hours, overnight) that batt is bad. Charge it overnight on a Battery Tender til it goes to a float charge. It should maintain 12.4 +/- volts for several hours. Get a battery hygrometer (the floating ball thingie that tells 1/1 charge, 1/4 charge, etc) and measure the charge in each cell. They should all be 1/1 or at least 3/4 charge.
The bike's alternator needs to put out more than 12.4 volts to keep the battery charged; the 13.5-14v is generally optimum.
'73 R60/5 Toaster
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