L4 as a bike light

Would it be ok to use a SF L4 as a bike light? I know the L4 gets really hot, especially if you're not holding in your hand. Are there any problems if the L4 gets too hot, or can it handle the heat?

Chuck289 said:

Would it be ok to use a SF L4 as a bike light? I know the L4 gets really hot, especially if you're not holding in your hand. Are there any problems if the L4 gets too hot, or can it handle the heat?

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The airflow from the bike moving will help cooling the flashlight. My Wolf-Eyes Defender II gets quite hot on the high level after a few minutes. I use it as a bike light and as long as I ride, it stays cool to the touch.

It's not the most efficient way to go, plus, as you said, the light gets very hot. I'd get a Fenix of some sort or maybe the NiteCore EX10 and run rechargeables. I use the two-fish lock block and a Fenix L1D on my Specialized Tricross. The strobe feature is actually very useful at dusk to make sure I'm noticed.

WildChild said:

The airflow from the bike moving will help cooling the flashlight.

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trust me, it won't help unless you bore a CPU heatsink and epoxy the head through the hole....I've rode in rain with the L4 on the handlebars and you could almost hear the rain sizzling on it [No I'm kidding of course but I can feel the heat on my handlebars even through two rubber sleeves on the hose strainers I used to mount the light on].

the outputs phenomenal with two...efficiency be damned, sometimes you gotta use what you got:thumbsup:

Yeah I didnt think that the wind would be enough to keep it cool. I have plenty of lights I could use. My main concern is that, if I do use the L4, will the excessive heat damage it?

I've used the L4 for biking but purchased a dual output tailcap to lower the lumens. I could twist it to high when I needed, but the low kept it from overheating.

Chuck289 said:

Yeah I didnt think that the wind would be enough to keep it cool. I have plenty of lights I could use. My main concern is that, if I do use the L4, will the excessive heat damage it?

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theoretically yes, but surefire hasn't said anything about it and reviewers here have ran the L4 full throttle for hours to test the runtime. Its more of a hazard than anything else though. Blisters is a PITA when its accidentally engaged and you tried picking it up by the head thinking its cold:shakehead

I own 3 L4s...theres not going to be a #4

Used my L4 on my daily commute for a while, no problems whatsoever. Just keep in mind to point it a bit more downwards than other lights, I got quite a lot of oncoming cars flashing their highbeams at me

There was a picture in the 2007 catalog of a guy on a mountainbike with two L4s attached to his helmet, one on each side...

Coop said:

Used my L4 on my daily commute for a while, no problems whatsoever. Just keep in mind to point it a bit more downwards than other lights, I got quite a lot of oncoming cars flashing their highbeams at me

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oh co0p...lets not forget the climate shall we? L4s makes great handwarmers too
I find it rather easy to balance the temperature of the KL4 by holding the L4 by the head while its engaged. Remember now, humans are liquid cooled.

JNewell said:

There was a picture in the 2007 catalog of a guy on a mountainbike with two L4s attached to his helmet, one on each side...

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I assure you that might never work as ideal as the pics have depicted partially due to Surefires utilitzation of luxVs. I believe they got the bin correct but in return let the tint vary...so I have one "green" L4, one "blue" L4, and one "white" L4...using them in pairs you will notice the tint shift gets very annoying. When I mounted two on my handlebars I usually let one run for a bit then the other.
"green" for outdoor color rendition
"blue" :thinking:
"white" looks great when used as a photography aid, plus a lack of a donut too

I would have thought that it would have been cool enough on a bike! Hehe.