InfidelCastro
Banned
Is the L2 battery tube skinnier? Are older U2's not capable of using 18650's? I keep hearing about this plastic piece that needs to be removed. Someone ejumacate me. 
Why will 17670's fit in an L4, but not an L2? Will 18650's work in all U2's?
- Thread starter InfidelCastro
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SCblur
Enlightened
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- Dec 30, 2005
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the L2 body is in fact a little skinnier. Just enough to not accept a 17670. In my opinion, the light would be perfect but for that one flaw. If I could get L4 runtime from my L2 via a 17670, all would be well in this world. Oh well.
As for the U2's, the timeline goes something like this: The very first U2's had no black sleeve, and the body was wide enough to fit a 18650. Then there came the revised body, which was just the same body, with a black sleeve insert to tighten the fit. SF claims it did this to fix a battery rattle problem with loose-fitting primary cells, but the downside is that 18650's don't fit in this version out of the box. The sleeve can be removed with a little coaxing, and there are various threads on the many methods for doing so. The most recent revision to the U2 body, however, is bad news for 18650 lovers, because Surefire has made the actual inside diameter of the aluminum body smaller. There is no removeable sleeve in this newest version, and the tube is only big enough to accept a 17670, but not an 18650. The only concieveable way to get a 18650 into this most recent version is to bore the tube out w/ a lathe or a dremmel tool (yes, somebody on CPF did this). There are many speculations as to why SF went to the non-sleeve body, but I don't think anybody knows for sure. If you're looking into a U2 for yourself, I would highly recommend getting the middle run (any U2 w/ the black insert). Your best luck at getting one is to visit some brick and mortar stores and inspect the unit yourself (that's what I did), or stake out the BST forum here until one shows up. Most internet vendors are likely to send you the newest version.
If you do go to a brick and mortar store, make sure you check out the lights thoroughly for a good switch, battery tube, tint, donut hole, etc. The U2 has been heavily scrutinized by many here, as a problematic light. Where there's smoke, there's fire, but I think much of the U2's bad press is undeserved. If you spend a little time to make sure you get a good unit, I think you would be highly satisfied. I hunted for quite a while to get a 18650-compatible one w/ great tint and almost non-existent donut, and it's now my favorite light.
Hope all this helps.
Cheers,
Josh
As for the U2's, the timeline goes something like this: The very first U2's had no black sleeve, and the body was wide enough to fit a 18650. Then there came the revised body, which was just the same body, with a black sleeve insert to tighten the fit. SF claims it did this to fix a battery rattle problem with loose-fitting primary cells, but the downside is that 18650's don't fit in this version out of the box. The sleeve can be removed with a little coaxing, and there are various threads on the many methods for doing so. The most recent revision to the U2 body, however, is bad news for 18650 lovers, because Surefire has made the actual inside diameter of the aluminum body smaller. There is no removeable sleeve in this newest version, and the tube is only big enough to accept a 17670, but not an 18650. The only concieveable way to get a 18650 into this most recent version is to bore the tube out w/ a lathe or a dremmel tool (yes, somebody on CPF did this). There are many speculations as to why SF went to the non-sleeve body, but I don't think anybody knows for sure. If you're looking into a U2 for yourself, I would highly recommend getting the middle run (any U2 w/ the black insert). Your best luck at getting one is to visit some brick and mortar stores and inspect the unit yourself (that's what I did), or stake out the BST forum here until one shows up. Most internet vendors are likely to send you the newest version.
If you do go to a brick and mortar store, make sure you check out the lights thoroughly for a good switch, battery tube, tint, donut hole, etc. The U2 has been heavily scrutinized by many here, as a problematic light. Where there's smoke, there's fire, but I think much of the U2's bad press is undeserved. If you spend a little time to make sure you get a good unit, I think you would be highly satisfied. I hunted for quite a while to get a 18650-compatible one w/ great tint and almost non-existent donut, and it's now my favorite light.
Hope all this helps.
Cheers,
Josh
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InfidelCastro
Banned
Thank you so much!!!! That tells me everything I wanted to know about those three lights.
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InfidelCastro
Banned
Are their any other lights similiar to the U2, such as the L5 that can use 18650's?
SCblur
Enlightened
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To my knowledge, I think the U2 is the only SF light compatible w/ the 18650 (without boring the tube out, of course). I don't know that for a fact though.
Lurveleven
Flashlight Enthusiast
SCblur said:
The external diameter on my L2 body is 1.5mm larger than on my E2L body, but the E2L takes 17670 cells but the L2 doesn't. Go figure.
SCblur said:
My guess is that that they already had many finished U2 bodies, and to fix the rattle problem they added the black sleeve insert. When they did a new run of U2 bodies it would be cheaper, and make more sense, to make the inner diameter smaller instead of adding a sleve insert.
Sigbjoern
easilyled
Flashaholic
AW in the dealer's section has a special rechargeable li-ion for the L2 that
is the right width - same length as the 17670.
(can't remember the number of the battery)
Look for his battery thread.
is the right width - same length as the 17670.
(can't remember the number of the battery)
Look for his battery thread.
easilyled
Flashaholic
Here you go ....
here is the link for the 14670 ....
http://candlepowerforums.com/vb/showthread.php?t=103009&highlight=14670
here is the link for the 14670 ....
http://candlepowerforums.com/vb/showthread.php?t=103009&highlight=14670
Planterz
Flashlight Enthusiast
I've often wondered why L2 and E2/L4 bodies aren't made to the same ID. I could understand going one way or the other, but beats me why one's larger than the other.
The 17670 would not fit in my new L4 but fits in the old square bodies(E2E etc),the 14670 would fit into my new L4 but the protection circuit would trip instantly (double cicking didn't work) if you ran the batt down to 4v or less then it would work in the new L4,however the 14670 would work with my old KL4 head just fine???? This may be off topic but the newer L4 seems to draw more juice than the old one.
Led-Ed said:
I'm confused. Just ordered an L4 and plan to use it initially with the two primary CR123's as designed. But I am interested in other options and don't know what to make of the 17670's now. Why would this cell even at 4v trip the L4 when it's designed to be used with the 6v from 2 CR123's? And assuming it does work in the L4, what runtime should I expect as compared ot the 1.3 or so hours of the 2 primaries? Finally - are there any NiMH options for this light? Thanks for any info here - I know it's a bit off topic...
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SCblur said:
I disagree slightly with your recomendation. I think the best U2 to look for is an early model made before they started using the plastic inserts. There were some other quality issues that started showing up right before they started using the inserts. The best quality lights seem to be the ones they made up through September 2005. My son and I do a lot of camping and the u2 with a 18650 is the perfect light especially for those 2-3 week trips. I've had one since early 2005 and as soon as I saw the postings about SF decreasing the inner diameter of the body I started camping out the for sale forums to pick up another older model for my son and got a great one. Sure, the newer models will still take a rechargeable 17670 but the run time is too short for me. The older models can still be picked up for $200 but that will change soon. Just communicate thoroughly with the seller about tint and donut.
InfidelCastro
Banned
With all the flashlight nuts on here, there's gotta be somebody with some machining skills who can make a run of 18650 bodies for 5W LED heads...
cheapo
Flashlight Enthusiast
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i am waiting for an e2u adaptor (u2 head on e2e would be sweet).
-David
-David
InfidelCastro
Banned
cheapo said:
I wonder if the E2E body will have enough surface to conduct that kind of heat away.
cheapo
Flashlight Enthusiast
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it should.... i mean...it can conduct the kl4 heat away.
-David
-David
