The New And Improved Unofficial R65 Forum V2

Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: Happy Eeyore on January 14, 2026, 06:48:39 AM

Title: relays 1979 r65
Post by: Happy Eeyore on January 14, 2026, 06:48:39 AM

From the right side of the bike rear to front I have five relays.  one in the fuse box then 4 mounted to main tube.  I think the one in the fuse box is the turn relay.  the others must be the  buzzer, the horn, the light and then the mystery relay with some sort of heat sink fitting which might/must  be the starter. . Any definitive knowledge about which is which.  My wiring diagram does not match up with the factory wire colors and it only shows 4 relays not 5.

Title: Re: relays 1979 r65
Post by: Barry on January 14, 2026, 07:55:15 AM

I have a 79 but it doesn't have 5 relays. That may be a difference between a European model and a US model which has a relay to turn off  headlight while the starter is in operation

I have:

flasher relay
Buzzer relay
starter relay

There no horn relay and being a Euro model no lighting relay.

You are not by any chance counting the voltage regulator which is the big can on the main tube bracket.

Title: Re: relays 1979 r65
Post by: Happy Eeyore on January 14, 2026, 02:51:33 PM

I cannot cross reference any of the numbers on the relays.  As soon as I get the battery back in  I will try and activate them and see if I can hear them switch.  My regulator is a large red topped device about 3 times the size of the relays.  One will be the starter, one will be the buzzer, one will be the two horns, one will be the headlight turn off when cranking, and one should be the turn signal.  My guess is the starter relay has the heat fins but that is a guess. Thanks

Title: Re: relays 1979 r65
Post by: Barry on January 14, 2026, 03:38:58 PM

After looking at both Euro and US wiring diagrams the horn relay must be an aftermarket fitment as it wasn't originally fitted and there was only one horn.

If you can open this word document it contains a lot of detail information on relays

Title: Re: relays 1979 r65
Post by: Steve on January 16, 2026, 03:05:59 PM

I have a 1979 R65, USA model. The bigger thing just forward of the relays is the regulator. The 3 relays aft of that are, from front to back, with the numbers from the wiring diagram:
34 - starter relay
35 - relay for accessory turn signal control - it does nothing on my bike
36 - light relay

Title: Re: relays 1979 r65
Post by: Steve on January 16, 2026, 03:08:33 PM

Those are just the relays under the gas tank on the right side of the frame.