Keen cyclists have long been using hub dynamo lights for commuting and touring to avoid the hassle of dead batteries and the subsequent ride home in the dark. I’ve used a few different hub dynamo lights with my SP hub dynamo systems over the past few years, including the B&M Lumotec whilst touring Central America and more recently the Dosun U1 for commuting and short bikepacking trips. These lights have done the job, but they’ve never been properly bright enough for technical trail riding in the dark at slower speeds.
Fortunately, some endurance MTB racers realised the need for a higher performance, mountain bike specific dynamo light. Racer/engineer Rob Dean began developing some prototypes in 2012 and eventually created the ‘Deanamo’ (a predecessor to the modern Revo). Fast forward four years – the next generation of super bright dynamo lights is now mature, with some very bright hub dynamo lights designed specifically for endurance mountain biking and bikepacking. There are two clear leaders in this new class: the Exposure Revo MKi by USE in England and the kLite Bikepacker by Kerry Staite in Australia.
I’ve recently been testing both these lights side by side, powered by an SP PD-8X hub dynamo courtesy of Charlie at IDC. I decided to write up my observations. Jump to the table and photos below if you’re the impatient type or read on for a more in depth comparison.
|Model||Exposure Revo MKi||kLite Bikepacker|
|Price||£180 GBP from various retailers||£179 GBP (distributed by Travers Bikes in UK)|
|Brightness||800 lumens||700/1200 lumens (switchable low/high)|
|LEDs||4 x Cree XPG R5 LEDs||3 x S4 BIN CREE XPG2 LEDs|
|Standlight||bright enough for hike-a-bike and pitching a tent; standlight is contained in the head unit||bright enough for hike-a-bike and pitching a tent; uses a separate module for the standlight|
|Total Weight||135 grams (inc single cable)||230 grams (inc splitter cables and top cap switch assembly)|
|Form factor||Compact, integrated bar mounted head unit with clever 'hot shoe' quick mount mechanism||Super compact head unit, but with a separate stand light circuitry module that requires separate mounting|
|USB charging||Potentially requires additional custom wiring and/or switch to work with separate USB charger||Bar mount or top cap switches and wire harnesses are available for use with separate USB charger|
|Power switch||Not included, but it's easy to unplug the cable from the back of the light||Burly bar mount or top cap switches are available separately|
|Rear light support||Built in rear light port, for use with Exposure Red-Eye lights||Not available as standard, but could be made to work with some extra wiring or a custom cable from Kerry|
|Installation/Mounts||Easy to setup with a clever quick release clamp, but mounting configurations are somewhat limited||Sets up with zip ties; more adaptable to different configurations. Three different mounts are included as standard and there are several other custom mounts available.|
Revo vs kLite
Let me start by saying that the Revo and kLite are both exceptionally bright for dynamo lights. They are many times brighter and more effective on dark trails than my previous dynamo lights, which are now looking more like your basic ‘to be seen’ commuter lights.
As any frustrated bike light designer will tell you, lumens ratings don’t tell the full story about light quality and many published specs can’t be trusted anyway. Still, the market demands a way to measure and compare luminosity, so we’re stuck with lumens for the foreseeable future. The Revo is rated at 800 lumens (the same as their tried and tested Joystick battery powered model) and the kLite is rated at 1200/700 lumens (high/low switchable).
It should be said, I have not carried out a particularly scientific comparison here. I’ve simply made some observations of the brightness and beam patterns whilst switching back and forth between. I had both lights mounted and just swapped the connectors back and forth on a few of my local trails.
I found that the kLite is noticably brighter than the Revo on the ‘high’ setting, with a reasonably wide pattern providing good peripheral coverage transitioning to an intense central region for long range illumination. The ‘low’ setting is noticeably less bright than the Revo and does not have the same side fill and long range, but is more than adequate on double track sections. Kerry writes about the high and low settings on his blog, advising to use the low setting most of the time and only switch to high at very slow speeds. He suggests that the ‘high’ setting may incur more drag, but honestly I’ve never been able to detect drag on any of my SP hub dynamos. I reckon he should rename ‘high’ mode to ‘gnarly singletrack mode’.
The Revo has only one mode, but I found it to be very effective as an ‘all purpose’ mode that more or less sits between the two modes on the kLite. The Revo beam pattern is more subtle, with smoother transitions and no intense hot spots. Once my eyes adjusted to this mode, I had plenty of clarity for side fill and long range, even though the Revo is technically not as ‘bright’ as the kLite.
The way in which these two lights ramp up brightness from a stop is notably different. The Revo takes a few seconds of rolling and lights up gradually (unless the standlight is already charged, obviously), whilst the kLite starts up more abruptly with two of the three LEDs going on first.
Both models are equipped with standlight battery to provide some lighting even after you stop pedalling. I originally bought my kLite in 2014 and I later became a bit disappointed with the standlight. It was not as bright as the Revo and did not last as long. I contacted Kerry in Feb 2016 and he offered to upgrade my light to the latest circuitry. So it’s worth saying that I am now testing the latest and greatest design as of April 2016, and older version may not be as bright and the standlight was effective. In my recent comparison, I found that both Revo and kLite standlights are sufficiently bright for navigating hike-a-bike sections or setting up camp in the dark. It’s certainly impressive that the Revo manages to achieve this without the need for a separate module.
Both head units are robust, CNCd and anodised aluminium and are well sealed to the elements. The cables provided with the kLite are especially burly, with some beefcake connectors and toggle switches.
USB Charging Integration
The power output available from a hub dynamo is not really sufficient to power a light and USB charger simultaneously, because the current (or voltage if connected in series) would be divided between them according to their load on the hub. As such, I’ve normally connected my light and charger in parallel with a switch to select one or the other. A hub dynamo light with integrated power switch will achieve essentially the same thing and this allows the USB charger to be connected in parallel (side by side) or in series (end to end). Kerry has a simple diagram showing a typical setup using as parallel circuit on his blog here.
The kLite has nailed the integration with USB charging, providing dedicated bar mounted and/or top cap mounted switches and splitter cables, both built with heavy duty cables and connectors. The Revo does not have an integrated switch, so you would need to purchase/design and setup your own splitter or switch and connect the charger in parallel with the light. This isn’t to say that the Revo can’t be made to work with a USB charging system, but it will require some additional consideration. Rumours have it that the MKii version is coming soon and may address this missing feature.
Installation / Setup
The Revo has the edge on ease of installation and portability, featuring a clever quick release bar mount with a sturdy swivel mechanism that allows you to aim the light left to right, not just up and down. The quick release is handy if you’re lucky enough to have two bikes equipped with hub dynamos, as you can buy a spare Revo mount and power cable for a second bike and simply move the head unit back and forth.
The kLite comes with three different mounts and there are toggle switches available for top cap or bar mounting. All the plastic mounting pieces are 3D printed from recycled plastic and have homemade look and feel – Kerry makes everything himself. The kLite head unit itself is mounted using zip ties, so it is a slightly more permanent installation (ie, no quick release). This is not such a big deal for a one time installation, but perhaps worth considering if you plan to share the light between two or more bikes.
On the other hand, the Revo comes with only a single bar clamp mount secured by an hex bolt, whilst the kLite comes with three different mounts. The kLite head unit is more compact and more suitable for alternate mounting positions, for example randonneuring style or out front ‘sweet roll’ mount style. Kerry and his customers post all kinds of different mounting setups on his Facebook page.
I’ve dealt directly with Kerry Staite (kLite) and he’s always provided quick and thorough support for his products. He’s quick to answer technical questions on his Facebook page. It’s got the personal feel of a homegrown operation, which is something I like to support. Exposure Lights are part of a larger group called USE, albeit still a relatively small company in the UK. I dealt with their support team directly on questions about the Revo and they were quick to respond with helpful info.
The Revo can be had in the UK for around £180, or even cheaper in the US where lower margins are the norm. As of June 2016, the kLite is now distributed in the UK by Travers Bikes. So whilst Kerry sells the kLite in Australia for $355, Travers Bikes is now selling them directly in the UK for £179. This now makes the kLite a more compelling option for UK bikepackers, where previously the Revo had the edge on the basis of free shipping in the UK.
Both of these dynamo lights are a massive step above the rest of the competition in terms of light quality and stand lights. The kLite is a slightly quirky but effective design and is highly adaptable to several different bike setups, especially where USB charging integration is concerned. Kerry produces several other custom mounts for various other use case combos. The kLite seems best suited for longer distance bikepacking events, where recharging of gadgets is a priority. The Revo is a more elegant one-piece system for those only wanting a lightweight lamp with minimal cables. It is possibly more for those wanting to swap bikes more easily.
Either way, you’re going to have a fantastically bright dynamo light that never lets you down as long as you can keep pedalling!
- Singletrack World Review of the Revo – a review of the Revo by the late Jenn Hill
- kLite FAQ – helpful notes by Kerry about his kLite
- Understanding Beam Patterns – about optimising optics for the best beam patterns
- The Confusing World of Lumens, Lux and Candela – How light brightness is measured
- Spike Light article about Lumens – more super light nerdery