Sigma Blaze Rear Brake Light

Sigma's Blaze Rear Brake Light has long burn times for such a lightweight package – though it has three LEDs, two only light up when braking is detected. That does mean it's not the brightest, though, plus there are no flashing modes and the short strap really doesn't stretch to fit wider seatposts; ours broke.

The Blaze is simple to use – it only has two modes. The first is auto-mode, which only switches on in low light, and the second is a simple always-on mode. It's only actually the top LED on constantly, as the bottom two only light up for braking.

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You cycle between modes, and turn the whole thing on and off, with the button on top. Unfortunately it's a button which can easily be pressed accidentally in your backpack.

The braking sensor works reasonably well, and doesn't appear to drain battery life too badly – something we've noticed as an issue with other brake lights.

Power

Sigma doesn't publish a lumen figure for the Blaze, instead claiming a visibility range of 500m. This is the longest of Sigma's rear lights, so its brightest option.

Lumens aside, I'd say the brightness is moderate. It's bright enough to be noticed, but not so bright as to be blinding. That means it's good in the dark or in poor visibility, but not so useful in bright daylight.

Run times

The flipside of a not-super-bright light is that you get long run times for the size and weight. Sigma reckons a burn time of 7hrs; this is hard to verify as it rather depends on how often the brake function is triggered, as presumably brake mode requires 200% more power than the single tail light. However, testing implies the 7hr figure is a real-world estimate that includes a fair bit of braking.

To take braking out of the equation I set it up on the bench indoors (my bench doesn't brake for anything) and it lasted 11 hrs. Also, it gave no signs of giving up after a 5hr ride, despite me running it for another four hours indoors... and even that only took it to the point where the warning light kicks in, which happens at 30% charge.

Add in plenty of braking and some low winter temperatures and 7hrs still seems very achievable.

No flashing, please

In my experience, brighter lights of this size can usually only manage around 3hrs on constant, which isn't quite long enough for my regular Sunday morning ride. So a light like this has its place.

Perhaps this is why the Blaze doesn't have any flashing modes – because the burn time is so long you don't need to extend it. Unless you think a flash actually makes you more noticeable to drivers; I don't.

Waterproofing

On paper the IPX4 (resistant to water splashes from any direction) rating might sound slightly disappointing, especially IPX6 is not uncommon at this price, for instance with Ravemen's CL05 USB Rechargeable Lighweight Sensored Rear Light.

However, holding the light under a running tap gave it no trouble, and neither did autumnal shitlaning.

The mount

The light is designed to be mounted to a seatpost with a rubber ladder strap. For me, this is quite limiting; I keep my tools in a saddle bag and there isn't enough seatpost showing underneath.

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There's no angle adjustment, so mounting this on the seatstays won't work. Mounting on the seat collar just about works, only it evidently requires stretching the ladder strap beyond what it likes – it snapped the second time I tried this. The distributor kindly sent a replacement.

This is not the only rear light with the same limitation, so I can't really mark it down for that. The flimsy rubber ladder strap however, is disappointing.

Value

At £27.99 for a light that has a daylight sensor and brake function, you are getting a lot of value for money.

There are similarly-specced units around the same price, though. That Ravemen CL05 USB Rechargeable Lighweight Sensored Rear Light (30 lumens) is slightly cheaper at £25.99, while the 50 lumen version is just slightly more at £31.99. As Sigma don't publish a lumen rating for the Blaze, though, it's hard to say which is the most comparable.

You can spend more, too; for example Lezyne's Strip Alert Drive costs £40.

Conclusion

If you're looking for a basic, reasonably bright rear light and have space on your seatpost, the Sigma Blaze last well and offers some impressive tech. Be careful with the strap and don't expect any flashing modes and it gets the job done well.

Verdict

Moderately bright rear light with long run times and a brake function, though the strap is a little flimsy