LED indicators - fitting resistors

I have some new LED indictors coming and after reading up a bit also ordered some in line resistors.. Anyone had any experience fitting these. It looks straight forward.. they just go inline on the indicator wires?

Yes, they do, but the simplest method is to replace the indicator relay with an electronic flasher: http://www.ebay.com.au/itm/Suzuki-Flasher-Relay-LED-GSXR600-GSXR750-GSF-1250-650-S-Bandit-TL1000R-DR-Z-400-/320810991407?pt=Motorcycles_Parts_Accessories&hash=item4ab1d33f2f#ht_4302wt_1058

kewwig wrote:Yes, they do, but the simplest method is to replace the indicator relay with an electronic flasher: http://www.ebay.com.au/itm/Suzuki-Flasher-Relay-LED-GSXR600-GSXR750-GSF-1250-650-S-Bandit-TL1000R-DR-Z-400-/320810991407?pt=Motorcycles_Parts_Accessories&hash=item4ab1d33f2f#ht_4302wt_1058

Which is what i did. Works great too. Plug and play.

It's extrodinary that we're still fitting resistors for indicators. I think it is just a normal addition, LED indicators go hand in hand with electronic relays. These relays work for any combo of LED or normal filament bulbs. Adding the resistor puts another two points of failure to every indicator and in fact it is a waste of power, something that is not in that great a quanity on a bike.

Bit of techo stuff now if you want to skip this and go to the next post....

The resistor is required to increase the load seen by the relay - it needs a certain amount of load to draw a specific amount of current to allow the relay's bimetalic strip to heatup at a certain rate - this causes the on/off affect. LEDs have very high resistance, thus very low current draw, in some cases they even appear to be open circuit to certain electronic sensors that are expecting a low impedence (resistance). The addition of the resistors for normal relays is to draw more current to trick the relay that it has the correct load. All this additional current is actually wasted in the form of heat, it does nothing to assist with the amount of light coming from the LED. Hence if you don't have the resistors, you have more power on tap for other things. I know it is only a small amount and for a short time, but for the sake of a $30 dollar relay change and never having to worry about resistors again, it is certainly worth the money IMHO.

My electronics may be a little dated, i.e. there is probably an electronic version of the bimetalic strip used these days, but the same prnciple applies.

I think the discussion of inline resistors to solve led indicator problems is a little off track.

Correct me if I am wrong (the wife frequently does!), but shouldn't the resistors go in parallel with the led light to draw a little more current i.e. to compensate for what the filament globe was drawing originally?

BanditDave wrote:I think the discussion of inline resistors to solve led indicator problems is a little off track.

Correct me if I am wrong (the wife frequently does!), but shouldn't the resistors go in parallel with the led light to draw a little more current i.e. to compensate for what the filament globe was drawing originally?

I've never fitted the resistors as I went striaght for the new relay, but yes that is how I thought they worked, the original bulb has to present a certain load to the relay, that load is too small with the LED by itself, hence the resistor to draw more current.

Raw LED's have only a 0.7 volt drop, putting them acros 12v needs to have a (small wattage) resistor in series for the correct voltage. If you look closely at most of the 12v LED's you should see the manufactors inline resistor inside the globe.

The after-market indicator resistors need to disapate the same wattage as the original globe (5 watts or more), hence why most of them are the larger gold heat load type.



Again, I have not installed an indicator with a resistor so if I have this wrong don't feel afraid to correct me.

barry_mcki wrote:

BanditDave wrote:I think the discussion of inline resistors to solve led indicator problems is a little off track.

Correct me if I am wrong (the wife frequently does!), but shouldn't the resistors go in parallel with the led light to draw a little more current i.e. to compensate for what the filament globe was drawing originally?

I've never fitted the resistors as I went straight for the new relay, but yes that is how I thought they worked, the original bulb has to present a certain load to the relay, that load is too small with the LED by itself, hence the resistor to draw more current.

Raw LED's have only a 0.7 volt drop, putting them across 12v needs to have a (small wattage) resistor in series for the correct voltage. If you look closely at most of the 12v LED's you should see the manufacturers inline resistor inside the globe.

The after-market indicator resistors need to dissipate the same wattage as the original globe (5 watts or more), hence why most of them are the larger gold heat load type.



Again, I have not installed an indicator with a resistor so if I have this wrong don't feel afraid to correct me.

Both correct, the voltage drop resistors are in series with the LED to limit the current through the LED. The load resistors are in parallel to put enough load on the flasher to make it work correctly.