Anyone try MR16 LED for MR16 Halogen?

[Giro]

Has anyone tried substituting an LED MR16 bi-pin bulb for the stock halogen MR16 bulb in their bike headlight? The brightest LED MR16 I've found is a 3 watt, 150 lumen, 12V DC LED MR-16 bulb sold by LED Liquidators for $39.97 LINK (http://www.ledliquidatorsinc.com/led-high-output-spot-lamps.php).

Next is the MR16-W4 White Nichia LED bulb (uses Three 1.3 Watt Nichia LEDs) LINK (http://www.superbrightleds.com/bi-pin.html). The MR16-W4 Cool model is claimed to have 120 lumens at 5500K and costs $38.95.

Much less expensive but lumens not stated is a 2 watt (so probably less lumens) 16 LED bulb for only $13.90 at LED Liquidators LINK (http://www.ledliquidatorsinc.com/led-spot-lamps-mr16-gu10-hr-jdr.php).

This all assumes the LED MR16 will not overheat the light fixture. Evidently incandescent MR16 bulbs radiate the infrared heat out the front while the LED M16 bulbs use metal fins on the sides. Thus some lights may be suitable for an LED substitute and other not.

Sooner or later I would think those of us with bike lights using halogen MR-16 bulbs will want to consider using a 12V DC LED MR-16 base bulb. Is now the time or should we keep waiting?

Thanks.

[DCCommuter]

I've been using this bulb:
http://cgi.ebay.com/MR16-12V-21-LED-Warm-White-Low-Voltage-SpotLight-Bulb_W0QQitemZ220150425910QQihZ012QQcategoryZ3240QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

It's a "to be seen" light, not a "to see" light. I run it side-by-side with a halogen, because I feel it makes me more visible.

One thing to be careful of is that sometimes LED MR-16's are slightly bigger than halogens and have trouble fitting. This one is the same size.

[Giro]

Thanks, I would not have thought of some LED MR-16s being larger due to the heat dissipating fins on the back of the bulb. The bulb you linked to is 2 watts but only 38 lumens, presumably because the light beam spreads widely. That makes it a good "be seen" light. The wattage is low enough that it apparently does not need a heat sink with fins in back.

Between the size and heat issue, I can see that LED MR-16s are not a simple "plug in" replacment. The light fixture must have enough space to the back and/or sides to accommodate the heatsink fins on the higher output LED MR-16 bulbs plus allow ventilation to dissipate the heat from the fins.

Time to look at measurements of the LED MR-16 versus the interior dimensions of the particular bicycle light. The same LEDwholesalers Inc ebay store also sells a 3 x 1 Watt 12V MR16 CREE 7090 XLamp LED WHITE 240 Lumen, beam width 38 deg, 6000 Kelvin. Link (http://cgi.ebay.com/3-x-1-Watt-12V-MR16-CREE-7090-XLamp-LED-WHITE-240-Lumen_W0QQitemZ220150518001QQihZ012QQcategoryZ16037QQtcZphotoQQcmdZViewItem). Dimensions are Diameter 1.96" or 50 mm, Length 1.9" or 48 mm. If this fits and gets sufficient ventillation, this could be the best candidate so far.