With two lights, run:

both high for lots of light
one flashing one steady or one high one low (alternate to extend battery life)
one on bars one on helmet
leave one home charging your spare battery (battery only charges installed in light)

Agree switch and usb cover are problematic. A smidge of silicone grease on the usb cover helps a lot.
Weight is not out of line (it has a large aluminum heat sink) and it looks fine to me.

I have no problems with the switch. I agree the USB port cover can be a littler cumbersome getting it back on, but it probably seals out the elements better that way, once you do get it in. Really that's an extremely MINOR annoyance with me. And almost everything in life has some minor annoyance or another. Rarely is anything ever 100% perfect.

By the way, the price of the Cygolite Hotshot 2-watt just got reduced to $21.36 on Amazon.com today. Crazy! Why do LBSs even bother to sell parts?

https://www.amazon.com/Cygolite-Hotsh...golite+hotshot

dangit I just paid $28 for it on Sunday!

No, no sweat. I was being picky, and expressing my opinions really for others who are picky as well. We all have different standards and points of comparison, so whatever each of us think in the end, well, it is what it is, and it's fine by me for us to hold divergent opinions. Thanks for clarifying your thoughts, but I didn't take offense, and of course you're right that it is an amazing little light.

That was the other factor in my decision.

Looks like the Metro lights come with the same bar mount, and the Metro might work better on a helmet due to smaller size and weight. However I'm guessing it doesn't use the same battery as the Expilion lights, right?

If you're referring to the 420 Metro, it has a built-in battery (not removable) and the re charger for the Expilion works with the Metro 420.

yeah see that wouldn't work for buying a light in order to have a spare battery and 2nd bar mount.

And now back to $27.15. It was probably a mistake, but I already bought one! I'd like to know the price-setting algorithm Amazon uses (scours the web for competitor's prices as far as I know)...

Used the helmet mount to attach the Exp 700 to the headband of sound attenuating earmuffs to provide light while blowing snow during the blizzard last night. It provided plenty of light on Low and worked a treat.

I think two lights for the situations listed, are a good idea.

I started out a couple years ago with the Cygolite Pace 150. Works good, thought 'high' was just a bit dim. Just recently got the Pace 400. Despite the number, not a whole lot brighter, but together, they can boost illumination up quite a bit. These two headlights, and the 700 appear to be using the same basic housing. That's simple, makes sense.

The switch...the way it cycles through the power levels, and learning the right amount of gentle pressure needed to activate it, took some getting used to, but I'm very comfortable with it now, and can easily change settings on the fly.

The cumbersome way the dopey little rubber USB cover meets up with its receptacle seems lame to me. I realize Cygolite, from a design perspective, is dealing with a very small area to work with on the back of the housing where the USB port is located, but perhaps with just a slight redesign of some of the plug's edges, it could meet up with the receptacle a bit more readily and still do its important sealing job. This would save users of its light, out in the cold and wet, and dark from having to use a fingernail or whatever, to try jam the plug back in after it's been accidentally been tugged out, which can happen easily when a hand brushes over the side of the housing towards the back where the cover is.

Yeah I agree the little USB cover is a bit fussy. The cover over the port on the Cygolite Hotshot is larger and much easier to deal with.

well I have to report that after my first actual night ride using this light, I'm absolutely thrilled with it. Ride time was probably close to 2 hours, and temps were in the upper 40's. I started out with the light on medium for the first half of the ride, but then cranked it up on high on the way back. I keep it aimed down towards the road to keep the hot spot out of oncoming drivers' eyes. Great light, couldn't ask for anything more, except maybe a second light on my helmet.

Those ExpiliOns are so light you could just get another one for the helmet. Perhaps consider the 400 lumen version for the helmet.

Yeah I'm thinking about it. Now do all the Expilions use the same 18650 battery and battery housing?

compatibility chart https://www.shop.cygolite.com/category.sc?categoryId=70

According to their spare parts chart (See Garfield's link above), not all use the same battery. However, I have loaned the spare battery for my Pace 400 (which originally came with a Pace 200) to a friend who has an Expilion 700 and it has fit and worked perfectly. I have also tested his battery in mine and it has worked fine.

Sent an inquiry to Cygolite asking what the difference was (thinking maybe the 700 used a higher capacity battery that would give me more runtime in the 400) but they did not respond. My suspicion is that they use the same battery and just charge more when you order it for the higher end model. If it was incompatible, they would key the housing so that it would not fit the other models.

Agree it's possible the batteries are the same, but I think it's equally likely they have a better spec for the 600/700 battery. It's possible that the 600/700 lights won't meet spec (brightness, run-time) with the lesser battery. There would be no need to key it differently as the batteries are not incompatible, but might only provide lesser run-times at the higher current draw of the brighter lights, or have higher ESR that could limit max brightness. ...but maybe not.

That's what I was hoping, and you would think they could then offer the 600/700 battery as an extended run battery for the lower end models. But the fact that they did not respond to a reasonable inquiry suggests to me otherwise.

Just called the support number at Cygolite. The rep says the batteries are indeed compatible, but slightly different. The lower powered Pace/Expilion models use a 2600 mAh battery and the 600/700 lumen models use a 2900 mAh battery.

So I would get a longer runtime from the higher end battery, but it would probably not be a huge difference. I'm figuring it could make 15-30 minutes extra runtime, depending on what intensity you run the light at. He didn't have any actual runtime figures for me.

He did also confirm that the Pace is simply the version that is branded for sale through Perfromance & Nashbar.

Ah so, if I really wanted a 2nd battery and mount for my 700, along with a bonus light to go with it, the 600 is probably my best bet. Might have to wait until next Christmas or something.

Must have been a short sale, it's back to $28 now (and also was yesterday).

Yes, the Cygolite expilion/pace headlights seem light...and compact, fitting easily in the palm of a hand. As for use of these lights on bike helmets, I don't presently have a light mounted on the helmet, but I might consider one if there was something on the market, better suited for that purpose than there currently seems to be.

There may be something obviously wrong with it that hasn't occurred to my non-designer mind, but here's an idea: it just seems logical for a company using basically good designers, which Cygolite seems to, drawing up and engineering a double ended light...white headlight on front, red tail light on back. Adapting the same basic light housing components, reflectors, switches and LED's used for the headlights, I would think a nice looking light using a 18650 could be devised. Two headlight bodies (total length 8"), or...one full length one and half of another(total length 6") could make two halves joined together using a kind of lock such as that used by the expilion/pace headlight rear battery cover.

Using two headlight bodies together, logically would allow two 18650 batteries, one for headlight, one for tail light, allowing power enough to maintain current headlight run times; though maybe an 18650 for the tail light is more than necessary. Maybe the weight of two cygolite headlights mounted to a helmet is more in that location, than people would be comfortable riding with.

A double-ended light wouldn't really be ideal. For helmet mounting, you really need the front light towards the front of the helmet, and any rear light on the very back side of the helmet. A double-ended light would have to go on the very top of the helmet, and if you're tilting your head down to get the front light on the road, the rear light would be pointing up into the sky. Not very useful.