TRELOCK LS906 BIKE-i PRIO DYNAMO FRONT LIGHT
169g (inc switch & bracket) £96.45
The Trelock LS906 Bike-i PRIO dynamo headlight is an 80lux (80,000 candela) front dynamo light that delivers a generous pool of light from relatively low speeds. Well suited to darker commutes and extended night rides, although the design has one or two quirks, which may alienate some riders.
Build quality is generally, what I’d expect from this price point. The anodized aluminium shell is solid and offered in an assortment of seductive colours. Being German, it complies with their extremely stringent StVZO standards. Most notably, this means lights, regardless of output must not exceed 200 candela above the central spot. To achieve this, the single diode is positioned backwards and projected through a computer designed mirror.
Putting this into context. To comply with this standard, some of the brightest rechargeable designs, including Moon Meteor Storm Pro would need to be aimed at the ground and only a few metres from the bike.
Trelock calls it “iBeam-Tec” but competitors and modern car headlamps all work to the same principle. Talking of diodes, I’m advidsed this one has a design life of 100,000 hours.
At this point it doesn’t suddenly die but will only operate at 70% of original capacity. Most decent quality dynamos and certainly anything complying with German standards have a “standlight” capacitor system. These ensure lights remain on for a minimum of 4 minutes when you’ve stopped, say at a junction/roundabout etc.
The LS906 comes with the standard stainless-steel fork mount but there is also a resin, handlebar bracket, which I opted for, given my rough stuff tourer and ‘cross inspired winter/trainer run the headlock type pre-load tensioning system.
I prefer these, especially on working bikes since they also offer some additional security, should a fork steerer suddenly fail. The composite bracket looks industrial but is similarly well-engineered, allowing the lamp to be set at your designed angle and entertains standard and oversize diameter handlebars and extension brackets. It also seems compatible with some Busch & Muller lights.
This is a similarly well-engineered, although slightly rubbery composite which not only does the usual on/off/auto thing but the two directional arrows enable the beam to be projected closer/further away as required.
Auto was my default and unlike some older, though generally dependable units, it turned on/off very predictably. Since oversized diameters are rapidly becoming the new standard, I was surprised, it only comes in a standard, narrow diameter.
Personally, I would’ve opted for an oversized diameter and provided shims to suit. Fitting to my fixed gear winter trainer’s oversized flared drops required some lateral thought and a longer screw.
Disappointing, and something to consider at the time of purchase.
On the up side, the white buttons glow green at night, easily spotted and operated in duvet type winter gloves.
The OEM wiring is designed with fork mounting in mind. If you’re taking this route, no problem. Being as ours was bar mounted, I needed to order something longer.
The diagram style instructions were a little misleading too, implying that the exposed wires are fed directly into the white plugs.
In fact, you press these home, while feeding the exposed ends into the black slots behind. I wasted several minutes, so you don’t have to. Credit where it’s due, the connection is extremely secure.
I’ve run ours with the Shutter Precision PD8 and Shimano’s Ultegra hub dynamos. By contrast, the switch is wired into the lamp. Unproblematic in the everyday sense but tricky should you be unfortunate enough to snag it mid tour, so weave carefully out of harm’s way.
80lux is at the upper end of dynamo output, so I was expecting something special. For those of you coming from 650/700lumen rechargeable torch types, 10-15 lux is sufficient in the seen-with sense for well-lit town riding.
I found a 15lux, budget 6V 3w hub dynamo system adequate on a daily commute through South London, although 30lux is my preferred, especially if you’re looking to navigate beyond the suburbs.
Paired with the SP hub, I was pleasantly surprised by the immediacy of output, within a few revolutions, I’d gone from a warm, pure white glow to the full 80lux.
Resistance is apparent, especially when the auto sensor engages “on” but it’s still nominal and unless I was doing a long run, I wouldn’t bother switching the system off.
Talking of which, like an increasing number of riders, I’m inclined to run lights during the day, although primarily a blinkey/torch type in a dedicated daylight preset, or 100lumen flashing mode.
On overcast morning commutes through the sticks, the LS906i produces a very assertive beam, which most drivers seem to register from around 30 metres, up to 50/60 around dusk and along unlit roads.
More about that shortly. Despite a seemingly flat profile, there’s a reasonable amount of peripheral bleed, which is particularly welcome in town.
Unlike Exposure’s Revo unit, (my all-time favourite) pretty much all of the power comes on stream between 5 and 10mph, which is really useful. Another neat feature is the German standard beam pattern, which projects a broad, though relatively pure carpet of light at the road.
No danger of dazzling anyone but sufficiently assertive, so you can just focus on upcoming hazards and maintaining a decent tempo, which is for the most part between 12 and 17mph in typical rush hour conditions. Admittedly, there are very slight fluctuations, say when you’re winching uphill but I’ve found it pretty minimal, even along some 1 in 7s and when I’ve been feeling decidedly weary.
Fork mounting has a slight edge when it comes to spotting holes and the occasional suicidal squirrel.
Aside from a few early trial 'n’ error sessions, optimising beam angle I’ve never had any difficulties with the bar mount. Letting rip along deserted backroads, the spot is good but has a slight, right handed bias. The reflector design scatters the flood differently to my Exposure Revo, which lead to a few interesting moments when carving into sweeping left handers.
Nonetheless, I adapted over the course of several three-hour night runs and there’s enough navigational bite for a steady 20mph, 25, in semi-rural contexts. Like most dynamo lamps, the road biased beam is good enough for short sections of canal/towpath at around 14mph but that’s pretty much your lot.
As I was expecting, the standlight will hold a decent charge for at least five minutes, which is quite a long time, especially in town commuting terms. It also adds some welcome safety, at junctions, or if you’re tackling a roadside mechanical in poorly lit areas.
That said, there have been a few times when I would’ve appreciated the option of turning it off. Most notably, when I’ve needed to nip into an off-licence for some chocolate based sustenance and AA batteries. Some areas, fine by day are decidedly dodgier by night and its continuous light drew unwelcome attention to my bike.
Some off grid tourists will want something capable of recharging USB devices. Those predominantly riding along pitch-black lanes might find its 100 lux stablemate a better buy-especially if you’re factoring a hub and wheel build into the package and I found the switch’s clamp diameter an odd choice. Nonetheless, the LS960i is well worth a closer look if you’re seeking a capable design for commuting through to endurance night riding.