The New And Improved Unofficial R65 Forum V2

Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: cobra407 on September 15, 2010, 08:42:58 PM

Title: battery question
Post by: cobra407 on September 15, 2010, 08:42:58 PM
there are three wires that hook to the battery. i know which is the ground and the positive. but there is a third wire-- which side of the battery does this one go to? thanks peter
Title: Re: battery question
Post by: Ed Miller on September 15, 2010, 09:07:23 PM
Where is the other end of the third wire?  My hot wire connector has two wires coming out of it, a big one to the starter and a little one to someplace else.  But they both connect to the same terminal lug, so I'm not sure what you have.

Title: Re: battery question
Post by: cobra407 on September 15, 2010, 09:15:57 PM
it sounds like there is one ground and two wires that run off the positive leed of the battery?
Title: Re: battery question
Post by: Rob Valdez 79 R65 on September 15, 2010, 09:30:54 PM
There should be one BIG wire going from ground (back of transmission, normally) to the negative terminal.  
(be nice to that bolt on the transmission!  Don't want to strip those case threads)

There should be one BIG wire going from the starter to the positive terminal.  It is probably red under the black sheath.

There should be one small wire going from the wiring harness (starter relay) to the positive terminal.  It should also be red.

I don't know what year bike you have, but you should be able to find the wiring diagram here:
http://www.pbase.com/tomfarr/electrical

Feel free to copy it to your computer.
Title: Re: battery question
Post by: Bob_Roller on September 15, 2010, 09:32:00 PM
If it is a smaller wire than the other two, it goes on the positive terminal, it powers all of the circuits of the bike, other than the starter .
Title: Re: battery question
Post by: Rob Valdez 79 R65 on September 15, 2010, 09:33:58 PM
And of course, everything is susceptible to the whims of previous owners.
Title: Re: battery question
Post by: cobra407 on September 16, 2010, 04:14:01 AM
thanks everyone!