Moon X-Power 780 front light

The X-Power 780 is the most powerful option in Hong Kong-based Moon's 'all-in-one' range, where the battery is integral to the light. A claimed output of 780 Lumens should put this light at the high end of the self-contained market, and be taking the convenience-lead fight to other systems using external batteries that might offer the same or only slightly more light. With an RRP of £99.99 it's certainly a premium outlay, however the X-Power 780 can be had easily from reputable dealers for as low as £64 at time of writing.

The packaging and User Guideline are a sublime journey into Chinese-English translation done cheap. You can't help but feel Moon would have done well to find an ex-pat propping up a bar somewhere in Kowloon and had the grammar checked for the cost of a few IPAs. Inside the box is a handlebar mount that might have been made by Isambard Brunel, it's that solid. It's good for 22-31.8mm bars - however fitting to 31.8mm required winding the adjuster all the way out then squeezing to get the knurled knob into the locking indentation. The clamping/hinge areas are away from the front where the clamp might interfere with brake/shifter cables emerging from under the bartape. It can also easily be mounted upside-down, and while this isn't in the user guide there's no reason to suspect this is any less secure an orientation. The light locks onto the mount with a reassuringly solid click, and is held very securely. Release is via a push-button on the left side that is doable single-handed with thinnish gloves on. The mount clicks a maximum of 45° to the left or right in 4 solid steps.

Also included is a helmet mount, USB 700mA-output wall charger brick and short micro USB cable. The Velcro-strap helmet mount has the unisex Velcro side towards your head when fitted to a helmet, so unless you have a moptop or wear a cap/beanie you're possibly going to get scratched up. The mount has an adjustable angle knob to get the beam just where you want it, but this means the mount is also quite tall, lifting the light a good inch above the helmet itself. The 207g weight of light and helmet mount coupled with the height of the mount means there is noticeable mass atop your noggin. A tight chinstrap and headband are required to stop the whole lot flopping about. This mount would have been much better securing the light flush with the helmet, but maybe there was a good reason for not going that route. More on that later.

The XP-780 has a removable 3300mAh battery, and you can get spares for £20 via the Moon store on Amazon. There's a coin slot in the rear of the battery to aid battery locking/unlocking - but a good press with the palm of your hand is enough to grip the slots and turn the battery. It's keyed, so incorrect insertion is impossible.

The XP-780 has a silver metal chassis, with black plastic at the front and rear. It charges via a micro-USB port underneath the lens at the front, covered by a rubber grommet. When charging the on-off button shows a slow blue heartbeat which turns solid once charged after about four hours using the supplied charger. The literature claims a one percent loss of charge per day and points out that run time decreases by fifty percent at zero degrees, an important consideration if using for winter rides. The run times are also listed as 'up to' - somewhat concerning, I'd have preferred an 'at least'.

Operation is via a single rubberised button flush on the top centre that doubles as a charge indicator, showing blue, then green, red and flashing red as the charge level drops in 25% steps. It's a single quick press to turn on and goes to the last-used mode, either solid or flashing, and always turns on at the brightest 'Overdrive' 780-Lumen level. A double press from off or while in use changes modes between solid and flashing, and it's a 1-second long press to turn off. The fact it's a single fast press of a flush button to turn on does raise the concern of accidentally switching on in a bag or pocket, which the removable battery goes some way to address. The area of the button is large enough that use through thick-ish gloves is possible.

In use the flashing mode is really a one-trick pony, with the only usable option being the 2.4Hz flash which appears to operate at the brightest power level. This falls into the category of 'stoopidbright' in my book, throwing back strong reflections from roadsigns at several hundred yards distance, even in daylight. In close proximity to vehicles in an urban setting it's overkill and simply wastes battery and is likely to annoy other road users. The other two options are an epilepsy-inducing superfast strobe and a rather daft SOS mode, only really of use to Enid Blyton re-enactors on Dartmoor after Timmy's scarpered.

There are dedicated side-light ports off the main LED to aid peripheral visibility, the main lens not being visible itself from the side. It has a 100° flood and 19° spot pattern, which means the spot beam brightness makes you tilt it to almost horizontal to get the optimal balance between distant and near-field illumination. As well as being not as recommended in the manual at all, that's wasteful of 50% of the output and highly likely to annoy oncoming traffic.

It's perceivably brighter than the Lezyne Power Drive XL, but does have nearly twice the Lumens in Overdrive mode. The XP-780 has a protection mode which will dim the light if it overheats - and run hot it does. Leaving it on full for a few minutes during discharge testing on an office desk where the tip of the light was accidentally touching a neoprene case resulted in a melted ring on said case, only noticed when it started to smell. You definitely don't want to leave this light in a bag with the battery fitted, the combination of an easily-pressed On button plus powering on at the brightest setting making for a potentially expensive discovery if it was piled in next to your new Gabba. Possibly this heat issue is why the helmet mount is so tall, to remove the chance of the lens area melting thin helmet shells.

On the bike over rough roads the bar mount performed admirably, with no movement or rattle. In full darkness the light emitted by the button is not intrusive as some can be, and was bright enough to inform without dazzling when looked at. Operating the button on the bike while wearing gloves did result in one panicky moment trying to find the button again after holding it down accidentally for too long and turning it off, but this was possibly an end-user issue. Once turned on in the highest power setting three other levels can be selected by pressing through the steps. This will get annoying after a few commutes, remembering to click through from Overdrive (1:30 run time) to High (2:50) to Standard (3:20) and Low (7:30).

For quick night riding on unlit roads the headline 780-Lumen Overdrive mode is the only real option. I found it possible to do 15MPH over potholed leaf-strewn damp lanes, but no quicker. In Overdrive mode there was approximately 15 minutes between each charge level - so after just 45 minutes you are into 25% remaining red+flashing button territory. Once into the bottom 25% there is no further warning of decreasing brightness / looming shutdown, the brightness slowly ebbing away until at the proclaimed 90 minutes it's only good for a very leisurely pace. The brightness continues to dim until dying completely at a total runtime of 3 hours. One notably smart feature is that should you get caught out by an unexpectedly longer ride, if you are in green, red or red+flashing then choosing a lower power level will change the button colour as it re-assesses capacity based on your new power level and remaining charge.

Using the XP-780 as a 'be seen by' daytime flasher means using the aforementioned 2.4Hz flash mode, with an advertised run time of 5:20. I managed to get 3:30 out of it before hitting 25% charge, meaning 5:20 is likely as a daytime flash outcome. For the brightness level this isn't bad - best for fast, open roads though.

So where does this leave the XP-780? Somewhere between a constant-output commuter be-seen-by for the three lowest light outputs, a club run front flasher for open/overshadowed roads, and a sub-90-minute slowish dark lanes option using the Overdrive setting - or longer with an extra battery or two. If you are flicking between highest and lowest modes to optimise run time between descents and climbs, be prepared for a *lot* of pressing to cycle through the four options and genuine excitement when you hold for a fraction too long. Lezyne's 'Overdrive Race Mode' which removes four options leaving you with Overdrive and Economy selected by a single quick press (think High/Low beam) is a damn good idea, and Moon would be well advised to do something similar to ease the pain of managing scarce power.

Based on the road.cc Light Comparator Engine the beam shape is almost identical to the Lezyne Power Drive 800 - but the Lezyne is much more user-friendly in terms of on-the-bike operation for a fiver less RRP. Having a maximum brightness that beats the competition is no use if power is so difficult to manage on the bars that the battery runs out prematurely.

Verdict

Well-made and bright with attractive replaceable battery option, but let down by a poor helmet mount, barmy flashing options and sub-optimal beam pattern

The light comparator

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