LED indicators

[linuxrob]

LED Indicators (WARNING - Waffle alert)

When changing your direction indicators from incandescent bulbs to LED’s you will have to modify the circuit a bit. You need a new flasher unit which is capable of giving the correct flashing rate, these are available from eBay for a very reasonable price whether you have a 2 - 3 or 7 pin flasher unit.

The other problem you may face is if you only have one repeater lamp in you dash. The way this system is wired you will find when you fit your LED bulbs and flasher all 4 indicators will flash. With standard filament bulbs the repeater lamp is fed power on both sides, one from the left and one from the right indicators and to complete the circuit it uses the “off” sides bulbs for a return to the negative side of the battery. This works because of the way all the voltage is dropped over the lit bulbs. There is a small amount of power left but not enough to light the standard bulbs. With LED bulbs the “off” ones will light up with this small amount of power flowing. (see diagram below).

Std GS125 wiring

 

The simple solution is to remove the repeater bulb altogether. This would prove the circuit worked correctly but would fail an MOT and would be easy to forget to switch of the indicators and cause even more problems for yourself and other road users.

Using 2 diodes, one from each side indicator, to feed the repeater bulb and a separate negative return will keep the correct function of the indicator circuit.

Modded with 2 diodes supplying repeater bulb

 

std wiring with indicators OFF

 

std wiring with right indicator ON

 

Modded circuit with right indicator ON

 

With the repeater lamp getting power from the left or the right main indicators it will only light if it can complete the circuit. An additional negative wire is run from the other side of the bulb to complete this circuit. When either side indicator is selected the diode on the non lit side blocks the return path stopping the “off” indicators lighting up. See diagram.

The diodes I used on my GS125 were 1N5408’s these are 3A diode, an 1N4007 1A diode would be enough but I chose the 3A ones for a bit of safety.

Here is the eBay link for the In5408’s

https://www.ebay.co.uk/itm/1N5408-3A-1000V-IN5408-3AMP-1000V-Rectifier-Diode-PACK-of-10/233442592150?hash=item365a434596:g:ysUAAOSw29Zd~6gL

Only other kit you need is a soldering iron, heat shrink and suitable connectors for your bike, together with a length of cable for the new negative connection.

Here are the 2 diodes ready to solder.

Soldered, Individually heat shrinked.

Then fully insulated and ready to fit.

Edited October 24, 2020 by linuxrob

[Tankbag]

[mention]linuxrob[/mention] useful stuff, thanks

[iangaryprice]

Wel done, very good information, well written and easy to understand.

[S-Westerly]

Well that confirmed that I won't be fitting LED indicators to my bike! Looks like far too much effort!

[TimR]

Big thing to do with ANY led indicator before fully fitting is check its visibility from a reasonable distance in position... Yes Leds may be brighter etc but have found on some of the lower cost ( even some model branded optional extras) have a certain operating angle to be effective and your bike going through the variable movements it will on a normal ride then their effectiveness is greatly reduced .

[linuxrob]

Big thing to do with ANY led indicator before fully fitting is check its visibility from a reasonable distance in position... Yes Leds may be brighter etc but have found on some of the lower cost ( even some model branded optional extras) have a certain operating angle to be effective and your bike going through the variable movements it will on a normal ride then their effectiveness is greatly reduced .

 

Good point Tim, I chose LED bulbs that would give as close as possible the spread of light as the normal bulbs and to work well with the reflectors and lenses, these are the bulbs i found to work well with GS125, Z500 and Bandit Standard indicator bodies.

https://www.ebay.co.uk/itm/1156-Ba15s-382-Reverse-Led-White-P21w-Amber-Indicator-Red-Fog-Brake-Light-Bulb/382668433644?ssPageName=STRK%3AMEBIDX%3AIT&var=651418214741&_trksid=p2057872.m2749.l2649