Frame Earth ?

I'm just thinking about how to wire the LED indicator warning light. 

" />

I'm mounting it on/near the bars, heat shrinking the cables, then running the cables along the left-hand switch cable, into the back of the headlight & splicing it into the indicators.  It's a twin cable from the LEd, which I've split to give two sets of cables, one for each indicator.  

I've already spliced a warning buzzer into the indicators by crimping both wires (indicator & buzzer) into a bullet & I'm loath to start hacking them apart again.  I intend to Scotchlok into the wiring (not a big fan of IDCs, but as it's hidden away, it's not likely to be subjected to moisture attack).  As space is a bit restricted behind the headlight, I'm wondering if I can earth through the frame or onto part of the headlight body using a ring terminal or will I have earth back through the earth cables ?

Hi Dave, I'm no auto electrician but when I've been testing things in the past? I've connected the live and just earthed things on to the frame without issue, I'd have thought earthing to the headlight bucket would be ok.

Earth originates from the frame, so most anything that is connected to it would do.

Thought so - just didn't want to risk any chance of electrical freak-out.

Cheers

Just make sure its the earth you put to the frame or you will have a shocking experience

Make sure the indicators don't all flash at once Dave seeing as you are connecting the light to BOTH indicators!

Thanks for voicing that niggle that I'd been ignoring !!  The more I've been thinking about it, the more I'm sure that's what's going to happen.  If it does, I'll just wire the second LED into the other indicator & fix them onto a shared bracket - good job I went back for a second one !!!

Well done that man & don't ask how I knew about it ok, walks off whistling quietly & looking behind slyly!!!

Anyway Dave you would not know which indicator was flashing otherwise!

Dave cant you wire it in to the tank cowling indicator light?

OK - the niggle I'd been ignoring now has a voice !!!  Ran a feed to the LED with the wires interconnected & it also lit the test light on the other wire.  So Pete is correct, putting the feed from two indicators into one set of wires to the LED will power up the second indicator.  (You must tell me how you discovered that fact one day, Pete)

Several alternatives - I could buy one of these LED Indicator Warning - however, I don't particularly like the tube style housing, I much prefer the cube of the one I have.  Secondly, I've already spent £1.00 on this one - buggered if I'm wasting that much money !!

Secondly - I could fit the second LED I bought - I don't really want to that for atheistic reasons - I have a problem with unnecessary symmetry.  I don't need to know which indicator I've left on - just that I've left one on.
   
Thirdly - as the Cap'n suggests, I could hook into the existing indicator warning on the speedo.  That could work, if I can find a suitable place to splice into - however, I'm a bit concerned about cutting into that part of the loom - looks like a cock-up waiting t o happen.

But it got me thinking - "how do they stop the same thing happening from the speedo?".  Traced through the wiring diagram & found that there's a diode fitted at the end of the circuit before it connects into the speedo warning light.  Googled a variety of phrases & found this article LED Indicator Diode Kit.  Don't bother reading it all - this is the relevant section 

"In order to simplify the wiring systems on many motorcycles (otherwise known as cost saving!), many manufacturers opt to install a simple dashboard indicator signal warning lamp which flashes when either the left or right turn signals are activated.

The simple circuit used to add the warning lamp effectively bridges the left and right indicator circuits. When the left indicator is on, the dashboard warning light is powered by the left indicator circuit as you’d expect, but it uses the right indicator circuit as its ground path. The same happens in reverse when the right indicators are turned on.


What this means is that a small amount of current will flow through the dashboard tell-tale light, into the opposite indicator circuit (the one that should be off) and hence through the front and rear indicator bulbs on that side. When conventional filament bulbs are installed this is not a problem since the current is small and filament bulbs require much more current before they light up.


A problem arises however when we upgrade a motorcycles indicator lights to use LEDs instead of the conventional bulbs. LEDs are much more efficient and use significantly less power which means that they turn on with only a small input current. So the small current flow through to the opposite indicators via the tell-tale light is sometimes enough to make the other indicators flash too. This results in all four indicators flashing (rather like having hazard warning lights fitted) when either direction indicators are turned on. Clearly that’s not very useful.


The best long term solution is to slightly rewire the dashboard indicator tell-tale light by using diodes to isolate the left ad right indicator circuits. (Diodes are small electrical components which only allow current to flow in one direction, a bit like a one way valve in plumbing)."


It's not exactly the situation I'm in - but it's close enough.  So at least I know it's possible & I'm on the right track & there is a solution out there.  I'm just in the process of contacting the author to find out if he is still selling the kit or alternatively, what diode he uses (I'm assuming that I don't just walk into Maplins & say "Can I have a diode please".  Does anyone on the site have sufficient electronics knowledge to answer this ? 


This has now become a bit of mission to make work - I can see it turning into a battle of stubbornness against common sense.

You can do it! great reading and research 

makes you wonder what did we do prior to the 90s and the invasion of the internet!

Spent a lot more time on researching things & a lot less time looking at porn !!

Hi Dave, if you have any old bits of electronic kit ie. a telly or radio pull it to bits and you will find one or more of these diodes in there or old wall plug type chargers.

I was putting an order in for some other stuff, so I put in an order for 10 diodes - £1.40 delivered !!  I'm assuming I just solder one from each live feed onto the single line running into the LED ?

As I remember Dave diodes have to point in the right direction ( the way you want current to flow )

Bands towards the top, I believe.  I'll have a dry run before I solder them up for good - what's the worst that can happen  ??? !!!!

It just wont work if it it wrong,they only flow one way.

It's not a heavy loading & the stuff only cost a couple of quid.