ONSRA BLACK Carve 4 (BC4): Gear Drive, 14S and What’s New vs BLACK Carve 3, 2 and 1

The ONSRA BLACK Carve 4 (BC4) is the fourth generation of our BLACK Carve electric longboard, and the biggest step the series has taken since the first BLACK Carve came out at the beginning of 2019. The short version: BC4 moves from the mostly 12S setups of earlier BLACK Carve boards to a 14S battery, swaps belts and direct-drive hub motors for an enclosed Gear Drive with a lot more power, gets updated TKP CNC trucks and a new flex bamboo deck, and is better protected against water and dirt. This article explains what changed, why, and how the BLACK Carve 4 compares with BLACK Carve 3, 2 and 1.

BLACK Carve 4 at a glance

• Battery: 14S3P, Samsung 50S cells, 51.8 V, 15 Ah, 777 Wh
• Drive: all-new Gear Drive with custom 170 Kv 6475 motors. The Street version has an interchangeable gear drive; the AT version has a bigger gear drive built for off-road
• ESC and remote: ORION ESC 14S 75 A, ONSRA NX remote with color display
• Trucks: TKP, CNC-machined, 37 cm / 14.5" wheel-to-wheel width
• Deck: bamboo with flex, 102 × 27.5 cm (40" × 10.8"), 1 cm U concave, 100 cm / 40" wheelbase
• Water resistance: IP65
• Two versions: BLACK Carve 4 Street with 115 mm rubber wheels and BLACK Carve 4 AT with 200 mm tires

All specs in this article come from the live BLACK Carve 4 product pages. The full table is further down.

Behind the BLACK Carve: perfected over years

The BLACK Carve has never been a "release it and forget it" board. In our behind-the-scenes video on the BLACK Carve 3 PRO, Fabian looks back at the start: the first BLACK Carve came out at the beginning of 2019, and back then people told us we had no chance against the big brands. What we did differently was keep updating. Each generation got several revisions, and whenever we saw something we could improve, we improved it.

That video also shows the themes that run through every generation, and that BC4 now takes further:

• Waterproofing. We designed a U-shaped O-ring for the BLACK Carve enclosure, tested boards in water and opened them up on camera to check the inside.
• Ride feel. Fabian has tested more than 250 electric skateboards on his YouTube channel. Very stiff boards felt harsh to him, very bouncy boards felt unsafe on rough ground, so the BLACK Carve series aims for something in between.
• Power, done quietly. The BLACK Carve 3 PRO got 66% more power with a 75 A ORION ESC instead of 45 A, a refined ESC tune, Samsung 50S cells and a new BMS to support the ESC.
• Trucks. Wide CNC TKP trucks that stay stable at speed and can still be set up to carve, plus a carvier bushing setup out of the box on the BC3 PRO.

BC4 is the result of all those years. In the words of the product page: it is the board we always wanted to build.

BLACK Carve 4 vs BLACK Carve 3, 2 and 1

Here is how the generations compare, based on our product pages, our own videos and the BLACK Carve 3 reviews linked on the BC4 product page. Where a value is not confirmed, we leave it open rather than guess.

The BC2 and BC3 battery and truck details come from Daniel Kwan's BLACK Carve 3 review, which is linked on the BC4 product page. The BLACK Carve 3 PRO details come from our own release and behind-the-scenes videos.

What BC4 does better than BC3

• More voltage and more energy: 14S3P with 777 Wh instead of 12S3P with 648 Wh, which is about 20% more battery energy.
• A lot more power with Gear Drive: no belt to slip and no exposed belt to clean.
• Updated TKP CNC trucks on a new bamboo deck with flex.
• Improved waterproofing, with the drivetrain enclosed.

What BC4 does better than BC2 and BC1

Everything above, plus everything BC3 already improved. BC2 rode on double kingpin trucks; from BC3 on, the BLACK Carve uses wide CNC TKP trucks. Owners of earlier boards can still upgrade: the ONSRA TKP CNC truck kit fits the BLACK Carve 1, 2 and 3 and the Challenger series, and the O-ring for BLACK Carve 2 and 3 keeps an older enclosure sealed.

From 12S to 14S: why the battery matters

Earlier BLACK Carve generations ran mostly on 12S batteries. The BLACK Carve 3, for example, used a 12S3P pack with 648 Wh. BC4 moves to 14S3P: Samsung 50S cells, 51.8 V, 15 Ah and 777 Wh.

Two extra cells in series mean a higher pack voltage. In practice, that means stronger acceleration and more pull on climbs, especially at higher speed. The product page puts it this way: BC4 "accelerates harder, climbs steeper hills with ease, and keeps pulling long after other boards run out of breath". The extra 129 Wh also gives you more energy to work with. Rated range is 50 km / 31 mi in ECO mode and 40 km / 25 mi in BRUTALE mode, both measured with a 75 kg rider.

Charging takes about 3 hours with the included 4 A charger. Like every ONSRA board, BC4 has regenerative braking, so some energy flows back into the battery on descents. In the first-look ride, Fabian recovers a good part of the battery on a long mountain descent but refuses to promise a fixed number. It depends on the mountain and the rider.

Gear Drive: a lot more power, almost no maintenance

The biggest mechanical change is the drive. BC1 to BC3 used belt drive or direct-drive hub motors. BC4 uses our all-new Gear Drive with custom 170 Kv 6475 motors. According to the product page, it delivers instant torque, whisper-quiet power, high efficiency and virtually maintenance-free performance.

Why we went gear drive, in Fabian's words from the first-look video: it is much easier to maintain. There is no belt anymore, no dirt can get in, and you basically don't have to do anything. The first-look video also shows that the gear drive comes in two sizes:

• Street (small gear drive): made for the 115 mm rubber street wheels. You can also run AT tires up to 165 mm. Swapping between street and AT wheels was quick and easy in the video.
• AT (big gear drive): made for 200 mm tires and off-road riding. Fabian recommends 200 mm tires for heavier riders and for anyone who mainly rides off-road.

How much power is "a lot more"? In our hill video, Fabian rides a BC4 AT prototype up a mountain road and holds around 50 km/h uphill without going full throttle. The production gear housing is slightly smaller than on that prototype, but the gear ratio is unchanged, so power and speed stay the same. The video is a demonstration, not a recommendation: wear full protection and always ride within your skill and local rules.

If you are deciding between drivetrains in general, our belt drive vs gear drive guide goes deeper.

Truck updates: TKP CNC, stable and carvy

Trucks were one of the biggest steps in BLACK Carve history. BC2 used double kingpin trucks. BC3 switched to very wide CNC TKP trucks, which Daniel Kwan described as more stable and more comfortable over bumps. The BC3 PRO then got a carvier bushing setup out of the box. In our behind-the-scenes video, we put it simply: say bye-bye to speed wobbles and broken kingpins.

BC4 keeps the TKP CNC concept, with updated trucks at 37 cm / 14.5" wheel-to-wheel width on a 100 cm / 40" wheelbase. In the first-look video, Fabian calls TKP "the best trucks ever" in his opinion, because they can be very stable at speed and still very carvy. Your setup decides which one you get. Removing the bottom washer makes the truck carvier, while a firmer setup adds stability for fast riding and rough mountain roads. On his first-ever race track session in Switzerland, Fabian found the BC4's huge TKP trucks a perfect match for the track: plenty of speed and stability, with around 50 km/h on the straights.

If your board ever feels nervous at speed, read our guide on electric skateboard speed wobble. It covers bushing setup by rider type and riding technique.

Improved waterproofing

Waterproofing has been a priority for years: we designed an O-ring-sealed enclosure (the replacement O-ring fits the BLACK Carve 2 and 3) and filmed our water tests. BC4 improves on this. The board is rated IP65, and the drivetrain is now an enclosed gear drive instead of open belts, so there is no belt to collect water, sand or dirt.

IP65 still doesn't make any electric skateboard a rain board. Our advice from years of rain tests stays the same. Avoid riding in heavy rain. If you get caught in the rain, open the board, let everything dry completely in a warm room, and don't charge it until you are sure it is dry. Check your enclosure screws regularly, because a single loose screw lets water in. Hold the remote behind your body in the rain, as it is less waterproof than the board. Our waterproof electric skateboard guide has more detail.

Deck, comfort and ride feel

BC4 sits on a premium bamboo deck with flex. In the first-look video, Fabian names flex as maybe the most important change of all, together with a slight drop at the front and back, so you always feel locked onto the deck. The deck measures 102 × 27.5 cm (40" × 10.8") with a 1 cm U concave, and the enclosure is made of a flexible special polymer.

For street riding, the 115 mm rubber wheels are much more comfortable on rough asphalt than classic PU wheels. Fabian still recommends AT wheels for beginners. In the first-look video, Fabian explains that the wheels were changed after long testing: they hold up longer, give more range and are lighter. Our electric skateboard wheels guide explains rubber, PU and pneumatic wheels in detail.

BLACK Carve 4 Street vs AT: which one is for you?

Choose the Street if you mostly ride roads and bike paths and love carving. Choose the AT if you ride gravel, trails or very rough roads, or if you are a heavier rider. Top speeds are technical values. Fabian's own rule from the first-look ride: above 50 km/h you need full protection, and nobody needs to ride a skateboard at 80 km/h. Strong brakes matter at any speed, so read how to stop an electric skateboard before your first ride.

BLACK Carve 4 full specs

FAQ

What is the ONSRA BLACK Carve 4?

The BLACK Carve 4 (BC4) is the fourth generation of the ONSRA BLACK Carve electric longboard. It combines a 14S3P 777 Wh battery, an all-new Gear Drive, TKP CNC trucks, a flex bamboo deck and IP65 water resistance, and it comes as a Street version with 115 mm rubber wheels or an AT version with 200 mm tires.

How fast is the BLACK Carve 4?

The product page lists 62 km/h (about 38 mph) out of the box for both versions: Street with 115 mm wheels, AT with 200 mm tires. With 165 mm tires, the Street version is rated up to 85 km/h / 53 mph. With 150 mm wheels, the AT is rated at 47 km/h / 29 mph. Always wear full protection at high speed.

What is the range of the BLACK Carve 4?

The rated range is 50 km / 31 mi in ECO mode and 40 km / 25 mi in BRUTALE mode, measured with a 75 kg rider. Real range depends on rider weight, terrain, temperature and riding style.

What is the difference between the BLACK Carve 4 and the BLACK Carve 3?

BC4 moves from a 12S3P 648 Wh battery to 14S3P 777 Wh, replaces belt or direct drive with an enclosed Gear Drive for a lot more power, gets updated TKP CNC trucks and a new flex bamboo deck, and has improved waterproofing (IP65).

Is the BLACK Carve 4 waterproof?

The BLACK Carve 4 is rated IP65, and its Gear Drive is enclosed. No electric skateboard should be ridden through heavy rain on purpose, though. If you get caught in the rain, open the board, let it dry completely and don't charge it until it is dry.

Should I choose the BLACK Carve 4 Street or AT?

Choose the Street for carving and commuting on asphalt. Choose the AT with 200 mm tires for off-road riding or if you are a heavier rider. The AT has a bigger gear drive built for off-road and weighs 15.8 kg, compared with 15.5 kg for the Street.

How much does the BLACK Carve 4 weigh?

The BLACK Carve 4 Street weighs 15.5 kg (34 lbs) and the BLACK Carve 4 AT weighs 15.8 kg (34.8 lbs).

Does the Gear Drive need maintenance?

Very little. There is no belt to replace or clean and no open drivetrain for dirt to get into. The product page describes it as virtually maintenance-free. Still check screws, bearings and trucks regularly, as on any board.