Kryptonite Street F-450 Front Cycle Light

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A couple of weeks back, I bought a set of lights to replace my older set, which last winter, I had decided the front was really to weak to see by when out after dark. The set I chose was really an impulse buy due to a very attractive offer for both the front and rear lamps for just £20 – the Kryptonite Street F-450 and Avenue R-45.

Kryptonite is not a brand I have previously associated with lights, but I was aware of it from their range of locks. I was happy enough to try the lights regardless at such a good price, but with a recognisable name behind them, that really sealed the deal. Unfortunately though, the R-45 rear light arrived damaged and is in the process of being replaced, so this article focuses solely on the front light – the F-450.

As its name suggests, the light outputs a maximum of 450 lumens, with a range of different operating modes to suit the environment and rider preference. It’s a single LED sealed unit powered by a non-replaceable battery, charged by USB power (micro-USB). It has two small holes to the side of the lens to allow a small amount of light to be visible at 90 degree angles (but not a lot). It is supplied with a handlebar mount which is secured to the bike and allows for quick and easy removal of the light unit itself. Operation is simple, through a single button that both switches the unit on/off and cycles through the operating modes. That button also contains a status indicator showing battery life or charging state.

There are six modes, as follows:

  • High steady – 450 lumens, continuous
  • Medium steady – 225 lumens, continuous
  • Low steady – 75 lumens, continuous
  • Daytime Pulse – pulsing at varying intensities
  • Nightime Pulse – continuous at 75 lumens, with 225 lumen pulse
  • Economy Flash – flashing at 75 lumens

The status indicator works as follows:

  • No light – unit is off.
  • Steady green – unit is on and battery level is above 50%.
  • Steady amber – unit is on and battery level is between 25-50%.
  • Steady red – unit is on and battery level is below 25%.
  • Flashing – indicates the unit is charging with its colour corresponding to the status above.

Using the light is extremely basic. Just give it a charge, and when ready to ride, clip it on to the mount, switch it on, cycle to the preferred mode and ride. Fixing the mount to the cycle is also straight forward – wrap the strap around the handlebar where the light is going to go, feed it back through the mount and pull tight – not dissimilar to pulling a zip-tie (but of course, this is removable) – and clamp the mount closed.

I took the light out on a test ride after dark, purposefully choosing a route that I knew would include a mixture of lit off-road tarmac paths, on-road sections and unlit off-road tarmac paths, the latter of which would be very dark being away from any over-spill illumination. I also took my older 100 lumen Cateye light with me so that I could compare the illumination between the two.

Unsurprisingly, the Kryptonite F-450 at full brightness swamped the illumination from the Cateye – of course it would at nearly five times the output – but I was also pleased to note that there was a good spread of light. The bulk of the beam was focused immediately in front of the cycle, but there was a good amount to the sides too, so that it was easy to keep an eye on the edge of the road.

In lit conditions, this is perfect and it provides a nice bit of extra illumination above what is provided by street lights, and I can’t see me needing anything more. However, in completely dark conditions where the sole source of illumination was the bike light, it was still a little bit low even at its maximum brightness. Make no mistake, it worked and I could safely follow the route, but the trip was necessarily slower – I couldn’t throw the beam forward enough whilst maintaining sufficient brightness to be able to see everything I needed to at speed. Instead I angled the beam lower so the intensity immediately in front of me was greater, but I couldn’t see as far ahead and had to move slower.

For my current riding, which is rarely after dark and if it is, tends to be in lit areas, this is sufficient. If I were to take unlit routes frequently, I’d perhaps rethink it slightly and go for something with yet more output – but this isn’t a criticism of the light, just a comment on choosing appropriate power for the areas being ridden. The output of the Kryptonite is what it is and allows for riding in most conditions, just with extra care in complete darkness – although I’d perhaps say if riding canal paths after dark, go for something more powerful .

The only real criticism I have of this light is with the mode selection – I think it’s too simple and a few more controls would perhaps have been beneficial. It would be nice to be able to easily switch between, say, ‘medium steady’ and ‘high steady’ quickly and easily (in the same way a driver can quickly alternate between low and high beams), then also being able to switch on pulsing as a separate function. With the light using a single button to cycle through all the modes, it’s not possible to be able to make quick changes that may be necessary depending on changes on-route.

For example, much of my ride was lit and I would probably have been fine riding with the ‘medium steady’ mode, but when moving into the unlit section, it would have been nice to press one button to enable the ‘high steady’ mode. Then, when returning to the lit section, another single press to go back to ‘medium steady’. Instead, to get from medium to high, it requires five presses of the button. At least then it is only one press to return down to medium, with it being next in the cycle.

The mode selections are also perhaps a touch too broad. I’m not sure I’ll find too much use in the ‘low steady’ mode at only 75 lumens, unless battery life is a concern – and for me who tends to charge after use most times, it rarely is. I’m also not sure about ‘night-time pulse’ either, with it being a low level continuous illumination with a high level pulse. I’d rather the continuous element be brighter – although, I appreciate this is more of a ‘be seen’ mode than one to see by.

Battery life on full brightness seems sufficient for at least an hour’s ride, perhaps 90 minutes. My test ride was about 50 minutes long and the status indicator was orange, indicating between 25-50% battery life remaining. Officially, this should be two hours and maybe it would stretch that far, but I wouldn’t count on it. Obviously, battery life is extended when using a lower intensity, pulsing or flashing modes, and when the battery has less than 10% of its capacity remaining the light will automatically switch to economical mode (flashing) to extend its life.

Overall, I’m very happy with the light for the riding I do, especially at the price paid. I’ve wanted a higher powered light for this dark season, but knowing that I don’t ride after dark or on unlit routes too often, justifying higher costs was difficult especially above the £50 mark and particularly were that for a single light.

At just twenty pounds, this was absolutely a no-brainer and really negates the little niggles I have with the control and modes. That price for the front light alone would have been great, but then factor in there is a rear light included in that price too. Off discount, the twin-pack is marked at about £75.00 – at that price, I might still have gone for this pack knowing that some front lights will attract that or more on their own – but I would be shopping around a bit more too.

This set was purchased from Rutland Cycles. At the time of writing, it is sadly now out of stock but can be found on Amazon for the higher price of about £50 – still a good price for a twin-pack of lights.

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