TurboTorch Casual 650/14Wh+ Casual Headlight [Yaqi Y-10]

The Yaqi Y-10 Headlight features dual Cree XP-G2 emitters with 4400mAh battery reserve. Features a subdued spill (flood) while maintaining reasonable throw in neutral colour temperature. This would have to be the best performing headlight under $50, and even better with two for $76... featuring:

• Two Cree XLamp® XP-G2 emitters offering outstanding 188 lumens per watt efficiency.
• Two semi-high drain rechargeable lithium-ion 18650 cells to sustain the fixtures high continuous discharge rates.
• Digitally adjusted output to maintain consistent brightness across battery draw-down.
• IP65 waterproof aluminium alloy housing with 360 degree adjustable holder (great for spotting house numbers in motion) and quick release.
• Convenient, modern USB Type C charging port connector.

A note on battery capacity:

TLDR - 4400mAh vs 6400mAh across two emitter fixtures is not +45% more capacity, it is approximately 3834mAh vs 5200mAh (+35%). When running 4 emitters a 6400mAh fixture delivers only 15% more capacity than 4400mAh at same light output.

1) Actual measured capacity across 3200mAh cells tends to vary greater than that of 2200mAh cells as shown in the diagram using data from testing performed by lygte-info.dk. This Y-10 fixture uses 2200mAh cells which typically better suit higher drain applications over 3200mAh cells which favour higher capacity. lygte-info.dk measured average 12.9% less capacity across 2200mAh cells, vs 18.4% across 3200mAh cells. The average measured capacity difference between 2200 and 3200mAh was 693mAh, not 1000mAh as the rated capacity would suggest.

2) A single Cree XP-G emitter typically draws 1.35 amp (5w), therefore a 4 emitter, 2 cell fixture will draw approximately 2.7 amps per cell at high mode. While this isn't considered "high drain" for 18650 cells, that configuration is reflective of the dotted red line on the graph. This Y-10 fixture would be somewhat between the dotted red line (2270mAh average) and the centre of the two blue lines (2608mAh average).

3) LED's are more efficient when at lower currents, but you obviously have a minimum expectation for light output - especially for throw. You are better having 4 lamps at half current, vs 2 lamps at full and as hinted to above, you want to spread the load across more cells to maintain range endurance. If you are wanting more than the Y-10, consider doubling them up or look at some options I've mentioned further below.

A note on Cree emitters, Cree XLamp® XP-G2 emitters appear to be the best choice for eScooter headlights:

• XP-G2 offers superior efficiency with 188 lm/W at binning conditions vs previous generation XP-G (146 lm/W), XT-E (178lm/W), XM-L2 (175 lm/W), XP-L2 (169 lm/W) and the low cost XP-E/E2 (122/137 lm/W). U2 bin designations apply to XM-L/L2 and XP-L. The XP-G2 is only surpassed by the XP-G3 at 190lm/W. Remember all values at binning conditions and usually operated in much more efficient conditions - e.g. Y-10 at high runs about 416 lm/W.
• XP-G2 offers a slightly more focused throw (120 degree) than the slightly wider XM-L and XP-L series (those series have T6 bin designation and are 125 degrees), XP-G3 (125 degrees) and a slightly larger spot than XT-E (115 degrees) and XP-E/E2 (115/110 degree). Note fixture lens makes further reductions to these pre-focus angles.

The only other battery operated headlight I suggest are the Sofirn SP36 series that power the Stonker series headlights by eScootNow. The SP36 is available with 4 * Samsung LH351D natural white 128 degree emitters with impressive 90CRI. SP36 is also available in 4 * Cree XP-L2 cooler offering 125 degree emitters. SP36 features 3 x replaceable button-top 18650 cells (totalling 9000mAh) delivering an observed 2200 lumens (nameplate 5200 lumens on the LH351D (or 6000 nameplate lumens on XP-L2), which is a crazy 3 times brighter than this Y-10 (brightness at nameplate cannot be sustained as it will start to step down with heat within 10 seconds). I run the SP36 XP-L2 variant for long-throw at between 1000-2000 lumens, which is ample and delivers at least 3 hours of runtime. The LH351D offers better CRI and less "rainbow" but with a trade off less brightness of only 149Lm/W (testing on the lower CRI's Samsung variants indicates being 8.2% - 4.2% more efficient than XP-L2 through 2056 - 4544 lumens range, highlighting the value of the brightness vs quality trade-off). This correlates with the previously indicated slightly lower nameplate max lumens on the Samsung variant. There is also a different software implementation between the versions. A SP36 Pro version featuring Luminus SST-40 emitter has also been released in 5000K and 6500K variants (early 2021), however these are much less efficient at currents typically desired for any reasonable runtime (i.e. more than 30 minutes). A lamp such as the SP series is essential for night riding at speed. Sub $50 fixtures do not cut the mustard alone but they do compliment the throw, provide convenient low beam, and a bit of redundancy.

I ran both Y-10 and Stonker SP36 XP-L2 concurrently. The Y-10 usually runs on low and points downwards to to a centre at around 3m in front of the scooter, simply because two-cell, two-LED lamps just cannot sustain long-throw over a reasonable range. The Stonker beams beyond that area to cover the long throw. In high pedestrian areas, I disable the Stonker as courtesy if it is running at high lumens. I am yet to find a battery-less fixture that has a good lens and do not really have interest as I'm not keen in drawing down on main scooter battery or adding additional battery "packs". The Stonker SP series are also good for day running as is a lot stronger to penetrate through the ambient sunlight to aid visibility of your scoot.