The New And Improved Unofficial R65 Forum V2

Technical Discussion => BMW Technical Q&A, Primarily R65 => Topic started by: tunnelrider on November 21, 2017, 04:55:40 PM

Title: Key switch issue
Post by: tunnelrider on November 21, 2017, 04:55:40 PM
Hi everyone,
My euro spec key switch seems to have a problem in the 'headlight on' position, the terminals get hot and the headlight fades. Can anyone see a problem swapping the park light terminal out and putting the headlight terminal on that key position? I believe it should be ok, the wires are the same gauge and at least I'll have a working headlight instead of just full beam by flasher circuit..

Edit; can I add that I've isolated the headlight fading problem to the key switch.  The rest of the headlight circuit is fine.
Cheers for any info in advance.
Title: Re: Key switch issue
Post by: mrclubike on November 21, 2017, 09:02:49 PM
It should be fine doing that
But I would put a relay in the circuit to take the load off of the key switch
It would help your head light be brighter any way and you may be able to go back to the headlight terminal to power up the relay
Title: Re: Key switch issue
Post by: tunnelrider on November 22, 2017, 11:51:04 AM
Thanks for your reply Mrclubike, yeah I can see a relay would be a good idea.
Cheers.
Title: Re: Key switch issue
Post by: georgesgiralt on November 23, 2017, 12:30:10 AM
Hello Tunnelrider,
Even if installing a relay is a "good thing" IMHO, it would be better to solve the initial problem : the switch overheating.
Overheat means, for me, high risk of fire. And this goes very fast on a bike.
I've had a similar problem where my bike used about 1A contact off. I discovered this with dead batteries even if charged all night long. They did not survive four hours standing still at work...
I solved it by a thorough cleaning with electronic contact cleaner (a huge lot of crap came out of the "device") followed by greasing the lock.
If yours is beyond help, there is a repop available from the usual suspects even if not cheap. (I plan to buy one and attach it to the Christmas tree with the name of the bike on the box tag).

Do not mess with electrics...
Just my 2c.
Title: Re: Key switch issue
Post by: Justin B. on November 23, 2017, 08:01:20 AM
I also think that the switch can be rotated into the "parking" position with any key, small screwdriver, etc...
Title: Re: Key switch issue
Post by: mrclubike on November 23, 2017, 11:01:55 AM
 I agree with  what George said.
It is better to try to fix it properly.
 
 For the Euro spec bikes
The ignition switch is carrying the full load of the head light (us spec bikes have a relay to shed this load from the ignition switch)
To stop this from happening again install a relay or at least get a LED head light bulb
Doing this can also protect your old dip switch
For that mater switch all the lights to LED
Your switches and charging system will benefit greatly 

Their is so many problems with the stock wiring and this is just one of them
And Dont get me started with the insufficient  fusing  :o
Title: Re: Key switch issue
Post by: tunnelrider on November 30, 2017, 04:19:18 AM
Thanks for your replies everyone. 
Quote
Even if installing a relay is a "good thing" IMHO, it would be better to solve the initial problem : the switch overheating.
Overheat means, for me, high risk of fire. And this goes very fast on a bike.
I've had a similar problem where my bike used about 1A contact off. I discovered this with dead batteries even if charged all night long. They did not survive four hours standing still at work...
I solved it by a thorough cleaning with electronic contact cleaner (a huge lot of crap came out of the "device") followed by greasing the lock.
George, the key switch was cleaned out of all gunk and regreased a year ago, after discovering the female spade terminal of the headlight wire in the same position was worn through, causing a similar problem to what I have now.  I suspect this has caused damage inside the key switch so need a new one too, unless there is a way to get inside them?  And yes, overheating and electrics= bad mix, well acknowledged, thanks.

Quote
For the Euro spec bikes
The ignition switch is carrying the full load of the head light (us spec bikes have a relay to shed this load from the ignition switch)
Mrclubike I know a headlight relay would ease the load on the key switch but if it worked for 30 years then failed because of the high resistance behind it (bad wire) could it be said that the design is actually OK?  Would I be able to test if my 'headlight on' position could power a relay?

Quote
I also think that the switch can be rotated into the "parking" position with any key, small screwdriver, etc...
                   
Justin, that's a good point I need to see how easily it can be turned but since I don't have kids around if someone did that they'll probably nick the bike!

Thanks guys, I'll start looking into the comparative cost/effort of;
a) installing headlight relay or
b) buying a new key switch.