Insidious C. 

My Cygolite Expilion has started exhibiting a binary fluctuation between normal brightness and dim. Cleaning the contacts (which have visible wear) hasn't helped. What would you do? Risk $40 on a replacement battery or replace the entire light for $90? The light has seen a great deal of use since I bought it 2 years ago and the battery is the original. I have an uneasy feeling that the bright-dim thing may not be related to the battery.

baldilocks

Batteries plus might be able to rebuild your battery (new cells) for much less than that. I use a LED bike light that I bought from harbor freight for nine bucks. It has worked quite well for at least three years. Mount was big for my bar so I wrapped rubber strip to shim it up. Bikepro LED Headlight If I couldn't have the battery rebuilt for a good price, you just might want the new one. Have they made any innovations in the last two years?

Leisesturm

Tricky. But you've lived with the light for 2 years. Have you noticed this kind of flicker when the battery is just about done? Does your battery level indicate a full charge or not? If you are getting a green full charge indication and the light is flickering, it isn't the battery. If the battery was dodgy you would be getting partial or no charge indication even though you have had the battery freshly charged.

Has the light ever been dropped or mishandled? Anything rattle when you shake it? Personally I would take advantage of an opportunity to try something different if I did decide to get another light. Might I recommend a MagicShine from Action Led? Similar price. Similar light output. You may become a convert.

Insidious C. 

The bright-dim thing is a recent development. I have been really happy with the Cygolites, both head and tail. But I appreciate the recommendations and will consider other brands. I haven't noticed a correlation between this behavior and battery state of charge, but I have been able to make it bright again by giving the light a smack.

baldilocks

Is there a spring that touches the battery? Perhaps stretching the spring slightly would make the connection better. I would have to try to fix it if I new I was going to replace it.

RubeRad

Light, $10. Pair of batteries with charger, $15. Two hose clamps, done.

Moe Zhoost

LED lights typically "dim" through circuitry that switches them on and off at a very high frequency (over 150 Hz s0 you don't notice flicker. Sounds like in your case the circuitry is bonkers.

fuzz2050

I'm going to disagree, at least sort of. Because you bought the light from an established company who probably cares about their reputation, ask them. Send Cygolight an email. Be truthful. Tell them how much you love their product, how much use you get out of it, and how sad you are that it's starting to break.

I buy a lot of cheap stuff, and most of it works great, but there is something nice about customer support.

RubeRad

That is a good point. It's not a question of having nothing and what should you buy, you already bought a premium product from a good company. I would definitely ask their advice; worst possible case, they tell you the light is shot, and you're better off than now because at least you know. Better possibility they tell you it's just the battery, best possible case, they might just send you a replacement light.

katzenfinch

If you decide to replace it, have a look at the Busch & Müller Ixon lights. They’re quite bright, and use rechargeable AA batteries.
Busch&Muller battery powered bicycle lights

Altair 4

Definitely this. It costs you nothing to touch base with the company and see what they suggest / recommend. Might even work out to your advantage.

noglider 

I highly recommend you contact Cygolite. I found their contact info on their web page and conducted a conversation entirely in email. I explained that my light didn't hold a charge after two years. They said send it in, and they will charge around $10 or $15 for a replacement battery. I sent it in. They sent me a replacement light and charged me $0.

I've heard only good things about this company, and my story is one of them. Their stuff is made in the US. How can they do that? It's sturdy stuff, and the mounts are really smart. Li-Ion batteries sometimes don't last as long as expected, so the smart thing is to replace them in this way. I have no hard feelings about it at all.

RubeRad

Thx for the info.

I tell you whut, I'm a cheapskate and I always try to buy generic, non-bike-brand when possible (thus my headlight being a regular flashlight and two hose clamps), but my wife found a Cygolite Hotshot on the road (fell off somebody else's bike), I bought a rack bracket and put it on my commuter, it is Amazeballs! I like it so much I would definitely pay the $35 or so to replace it if I lost it.

e0richt

I agree with this... though I don't use the flashlight there are cree lights that are 1000 lumens that are fantastic for the money (I bought mine for about 20.00)...


but if needed I would go with this flashlight...

Insidious C. 

I emailed customer service over the weekend (they got the same info I posted here) and got a response this morning. The said send it in for repair or buy a battery and they would assist if that didn't fix it. The latter is best for me since I commute by bike every day. But...I looked at my battery under the microscope at work today and the "wear" marks had a dark appearance. So I scraped with an exact-o and found that that dark stuff came off. So I scraped until the whole area was nice and shiny. I disassembled the light enough to get at the mating contacts also and they looked okay. I'll be riding home in the dark tonight and I'll post results tomorrow.

baldilocks

Get a reflective vest. I use a blinker in the back and a light in the front. Monday on the way to work a pickup truck pulled up to me and the guy said I should get a reflective vest. As much as I hated it, I knew he was right. Picked one up after work and was much more visible the next day.

Insidious C. 

Update: During last nights commute there was no bright-dim behavior at all. Rubbing with cloth and alcohol apparently wasn't enough, but some very targeted and thorough scraping with an x-acto seems to have restored the connection.

Any Material Scientists in the house? I would have thought these materials would not corrode. Perhaps this is an example of "fretting corrosion."