turn signals

[mvalenti]

I bought 2 pair of mini stalk turn signals the other day and had an unexpected problem. I installed the rear set like this; battery to key, to fuse 10A, to flasher relay, to switch (toggle) to lights. turned the key, flipped the switch and it worked... now to connect the front, I have 2 wires that run to the front of the bike for the front set, not marked right or left, duh..... I flipped the switch and found the correct wire to power the correct turn signal, constant flashing for about a minute, made the connection and thats when it got interesting...
I looked back at the left rear and it was flashing but the color seemed "off", not as amber as the front. Went around back and noticed the housing was starting to melt!!!! I shut off the power and let the turn signal cool a bit.. The bulb's amber color was completly evaporated...Also the bulb clearly was marked 12v 3A. It was only hooked to battery power. Any ideas on why this happened?
I spoke with the shop that ordered these for me, they thought since I bypassed the turn signal control and maybe that drops some voltage, that could be the problem. I said, ok, but the lamp is still rated for 12v operation.... I'm thinking its a bad bulb/unit.. They are replacing it anyway, but it still made me wonder...

-Mark

[Matchless]

Not sure exactly what you bought, but the miniature stalk types with the small "21" Watt bulbs painted orange sold as aftermarket that I have opened were mostly of poor quality.
The bulb holder tends to come loose and a hot bulb touching the plastic may melt it. In my opinion just too much heat in too small a cavity.
Lower wattage bulbs, which run cooler, may be too weak to be seen in daylight.

If you are going small on flashers you might as well rather go LED which do not have a heat problem, but will require a special flasher unit.

[BassCliff]

Hi,

Any corrosion in the circuit causes extra resistance, forcing it to pull more amperage which leads to extra heat. Try cleaning all connections and grounds to eliminate that possibility.


Thank you for your indulgence,

BassCliff

[mvalenti]

Thanks for the input all. Unfortunately there was no corrosion as all parts and harness were brandy new. However something else caught my eye and thanks to the replies here made me think back to ohms law... Volts x amps =watts.. My lamps were 12v 3a... 36 watts!!! That's flipping hot. So I bought some 12v 4.5 watt bulbs, dimmer yes but bright enough... And there running cooler. I did purchase LED directionals however today. For longevity... Thanks again!

[Steve]

I spoke with the shop that ordered these for me, they thought since I bypassed the turn signal control and maybe that drops some voltage, that could be the problem.

There is only one device on the entire bike that is designed to work at less than the nominal 12 volts, and it's NOT the turn signals.

Good to see that you worked it out,

.

[mike_of_bbg]

If you are going small on flashers you might as well rather go LED which do not have a heat problem, but will require a special flasher unit.

I just replaced my flasher the other day, type 552. The $3 ones at NAPA appear to be electronic (although they are labeled thermal, go figure). So not all THAT special. They're labeled "load independent", but the bigger clue is that they start in the OFF state; seems to be physically impossible for a true thermal flasher.