Mid-mounted ebike gearbox simplifies drivetrain, smoothens shifting

South Korean startup Kosmos has made its Indiegogo debut with a tech-packed ebike named the Nova7. The PAS commuter features a mid-mount internal gearbox, rear-hub motor with responsive torque sensing, and a low-maintenance belt drive.

The folks behind the Nova7 reckon they’ve been developing the 5-speed mid-drive gearbox since early 2021. A few prototypes later, and the final version was ready for installation in a mule ebike by September of last year. More design tweaks followed, ahead of field testing in the pre-Indiegogo prototype Nova7 a few months back.

The rider switches gear ratios using what looks like a modified Shimano shifter at the handlebar. The weather-sealed gearbox is mounted at the bottom bracket of a smooth-welded 6061 alloy frame that’s been specifically designed to accommodate it. Cabling has been routed internally to maintain clean lines.

The Nova7's mid-mount 5-speed gearbox has been 3 years in development
The Nova7’s mid-mount 5-speed gearbox has been 3 years in development

Kosmos

Powering the commute is a 250-W AKM rear-hub motor that produces 35 Nm (25.8 lb.ft) of torque. Top assist speed hasn’t been given, but we’d guess it’s likely going to be 20 mph for the US and 25 km/h on its home turf of South Korea. The ebike will ship with a removable 374-Wh downtube battery make up of Samsung cells for up to 46 miles (74 km) of per-charge riding.

Kosmos has replaced the messy chain-drive setup for a Welltrans carbon belt drive for the promise of clean and quiet riding. A color display has been integrated into the stem for at-a-glance status checks, and connects to a companion mobile app supporting keyless activation, GPS positioning and over-the-air updates.

The Nova7 rolls on alloy rims wearing 700x38C Kenda Kwick Trax tires with Tannus Armour inserted between the tube and tire for up to 5 mm of puncture protection (including sidewalls). Stopping power comes courtesy of Shimano MT200 hydraulic disc brakes with 160-mm rotors.

Kosmos promises a smooth, quiet and clean motor-assisted commute
Kosmos promises a smooth, quiet and clean motor-assisted commute

Kosmos

Rounding out the key specs are a 1,200-lumen LED headlight and braking tail-light, plus turn signaling to the rear. The ebike is reported to tip the scales at 55 lb (25 kg). Accessories such as a kickstand, fenders and rear rack can be optioned in. The startup also boasts that the frame, rims, spokes, motor, belt and gear unit can be fully recycled at the end of their operational lives.

The Nova7 is currently raising production funds on Indiegogo, where perks start at US$2,400 – representing a 50% saving on the suggested retail price. The usual crowdfunding cautions apply, but if all goes to plan with the remainder of the campaign, shipping is estimated to start from March 2025.

Affordable E-Bike with a Revolutionary Gearbox [Crowdfunding Kickstarter Indiegogo]

Source: Kosmos

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