The New And Improved Unofficial R65 Forum V2

Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: Crossrodes on June 06, 2009, 06:49:06 PM

Title: Charging Circuit Wiring Diagram
Post by: Crossrodes on June 06, 2009, 06:49:06 PM
Does anyone have a wiring diagram for the charging circuit for a '79 R65?  

I have checked the diagram in my Clymers manual but it doesn't give me sufficient detail.  Specifically what I am looking for is how the 3 wire connector/cable that connects the diode board to the alternator should be connected ie: which wire runs to which terminals.  I disconnected it thinking that the plug would only go back in one way...Wrong!!!  

In reading a write up of the charging circuit that was posted here it may not matter how the cable is connected as each of the 3 stator coils feeds the diode board to rectify the 3 phase AC into DC.  Does anyone know if it matters how the alternator is connected to the diode board?  

Mike

Title: Re: Charging Circuit Wiring Diagram
Post by: Bob_Roller on June 06, 2009, 07:16:16 PM
I've got Rick Jones Boxer Charging manual, and it states the three wires from the alternator plug to the diode can be connected in any order .

If you look at the alternator plug, and the diode board , can you see any letters at the terminals  like W, V, U ?

That's what the wiring diagram shows, so if you can find co-responding letters on each component, connect the wires to the appropriate letters on each .
Title: Re: Charging Circuit Wiring Diagram
Post by: Crossrodes on June 06, 2009, 07:48:01 PM
Thanks Bob.  

I thought it might not matter how they are hooked up.  I did see the WVU on the alternator and marked those connections.  Unfortunately I can't see any markings on the diode board...but if it doesn't matter how things are connected....
Title: Re: Charging Circuit Wiring Diagram
Post by: Andy-Gadget on June 06, 2009, 08:49:53 PM
Any order is fine.

The output of the alternator is three phase power at an RMS voltage the same as the bike system and a frequency of the engine speed in revs per second by the number of poles on the rotor, six from memory.
All that will change if they are connected differently is the phase rotation order will be different, makes a difference if it was staying three phase, but as it is being rectified at the diode board to DC it makes no difference.

Too much information I guess, but knowledge is power.
Title: Re: Charging Circuit Wiring Diagram
Post by: Barry on June 07, 2009, 06:34:07 AM
Is this charging circuit diagram for an R80GS any use ?

Can't remember where I got it.
(http://)
Title: Re: Charging Circuit Wiring Diagram
Post by: Bob_Roller on June 07, 2009, 08:15:11 AM
The charging circuit for airhead bikes from '78-'95, are all the same, all of the components are interchangable .
Title: Re: Charging Circuit Wiring Diagram
Post by: Crossrodes on June 07, 2009, 09:41:26 AM
Barry that's great.  I printed it out and will add it to my service manual.  Thanks.

I have one more request...do you have a similar diagram for the ignition circuit that you could show here.  I'd like to ensure that I have everything wired correctly.

Thanks to all for your feedback.
Title: Re: Charging Circuit Wiring Diagram
Post by: Barry on June 07, 2009, 12:46:21 PM
Mike,

Sorry I don't have a specific diagram for the ignition circuit only a full circuit diagram for the 79 R65 which is nothing like the same quality and probably the same as your Clymers manual. I think mine was scanned fron a Haynes manual.  Let me know if you want me to post it. It's in a Word document though.
Title: Re: Charging Circuit Wiring Diagram
Post by: Rob Valdez 79 R65 on June 07, 2009, 02:21:03 PM
Mike,

I've been taking pictures of my "'79" as I've been taking it apart.  I didn't get a picture of the beancan before I removed it, because I figured I could remember that much! lol!

http://www.pbase.com/tomfarr/rebuild

You may find the notes helpful.
Title: Re: Charging Circuit Wiring Diagram
Post by: Crossrodes on June 07, 2009, 02:45:55 PM
Barry, thanks but I think I've got it solved.  

Rob thanks for posting the pics.  It looks like I got the wiring done ok according to the pics.

I also thought I wouldn't need to take any pics...and then one thing led to another.  Coulda, woulda, shoulda....Oh well it's all good experience.
Title: Re: Charging Circuit Wiring Diagram
Post by: Barry on June 08, 2009, 04:23:52 PM
Mike

Glad you got the ignition sorted but you started me thinking.  

I carry an A4 print of the full wiring diagram on the bike folded up neatly in the handbook holder under the seat. To be honest though without my best reading glasses and some good light it would be quite useless out on the road (Can any other older members identify with me here).  

What I really need is a simple ignition diagram and as I couldn't find one on Google images I've drawn one. It's not up to the same standard as the charging circuit and the +ve feed from the battery to terminal 15 on the Rear coil is somewhat simplified.

In practice if you lost the 12V feed to the rear coil a temporary link from the battery +ve would get you home.

The attached image is a very small file but will probably display quite large for which my apologies.

(http://)
Title: Re: Charging Circuit Wiring Diagram
Post by: Rob Valdez 79 R65 on June 08, 2009, 05:41:44 PM
Mike,

One other thing, on the early, points models, the front coil MOUNT had a tendency to break off from the frame.  When that happened, it took the main harness ground with it.

You have two obvious choices here.  You can have the bracket welded back on & hope, or do what I did, and strap that front coil on with a couple of extra-long hose clamps.  I found mine in an ACE hardware plumbing section, on these big rubber couplings: http://7gifts.com/Flexible-Coupling-P105642-Flex-Coupling/M/B000BPDGUU.htm

Then I had to relocate my ground wire:
http://www.pbase.com/tomfarr/image/90927252/large
Title: Re: Charging Circuit Wiring Diagram
Post by: Crossrodes on June 08, 2009, 09:35:05 PM
Excellent drawing Barry.  Thanks.  I'll print that out and keep it.
I know what you mean about reading the drawing in the book.  

Funny you should mention that Rob.  one of the things I came across was a broken bracket and a hose clamp holding the front coil.  I ordered and installed a new bracket thinking that would be the end of that problem.  I guess I'll re-install the hose clamp as a little insurance in case the bracket breaks again.
Title: Re: Charging Circuit Wiring Diagram
Post by: Rob Valdez 79 R65 on June 08, 2009, 09:45:24 PM
The only two-coil models that have not had their front bracket-tab break yet are that way only due to low mileage.  They will fail.  I bought my bike in 1980, and it was probably only 2-3 years before it broke.
I used zip-ties all that time until I replaced my coils a few years ago, and thought I'd upgrade to hose clamps! :)
Title: Re: Charging Circuit Wiring Diagram
Post by: Justin B. on June 09, 2009, 01:34:29 AM
I have zip-ties securing the rear coil on my '81 R100...  I really need to fix it some day. Yeah, right...  ;)
Title: Re: Charging Circuit Wiring Diagram
Post by: montmil on June 09, 2009, 06:50:03 AM
Quote
...To be honest though without my best reading glasses and some good light it would be quite useless out on the road (Can any other older members identify with me here).

Hurt me. Raise your hands, boys.

Here's a tip. Avoid using a magnifying glass in bright sunlight to read tiny print. I set fire to my last "on-board" instruction sheet!  ;D

Monte