Jasion Roamer ST 1200W Step-Through Commuter

750W rated rear hub with 75 Nm torque (Jasion markets 1200W peak, a brief boost) is a sensible spec for a commuter, and the listing title states a 28 MPH top assisted speed. We have not ridden it, so we cannot tell you how it climbs. Cadence-sensor pedal assist is the standard Jasion limitation: power switches on/off rather than ramping in proportion to your effort.

The 528 Wh battery is smaller than the 720 Wh on the EB5 MAX and Vivi ACE07, which is the load-bearing trade-off. Jasion claims 40-62 mi range. Our planning estimate, not a measurement, for mixed commuter riding (PAS 3, a 170-lb rider, mixed terrain) is 28-38 mi per charge, closer to ~22 mi if you hold 28 MPH, and cold weather typically costs lithium packs another 15-20%. Plan around 30 mi practical range. Removable for indoor charging, which matters on a Class 3 bike where you'll want maximum range for road commuting.

Step-through frame + Class 3 (28 MPH) capability is a less common combination in this price tier. Many Class 3 bikes use high-top-tube frames (the Jasion EB5 MAX is one), partly because a closed frame is easier to make stiff. A step-through frame needs more careful tubing layout to limit flex. Jasion publishes no frame-stiffness data and we have not ridden the bike, so we cannot say how it handles at a sustained 28 MPH.

The trade-off is access: if you have knee, hip, or balance issues that make swinging a leg over a traditional frame difficult, a step-through solves the problem. Another Class 3 step-through on Amazon we review is the Heybike Cityscape 2.0, for $609 (as of Sep 29, 8:10 AM EDT, subject to change), with a smaller 468 Wh battery and mechanical disc brakes.

The Amazon title explicitly says "UL2849 Certified", which is more concrete language than the "UL 2849 testing" wording on the cheaper Jasions (which is more ambiguous about whether the certification is third-party-issued or just internal testing). UL 2849 is the e-bike electrical-system standard that incorporates UL 2271 cell/pack testing by reference.

This matters for:

• NYC Local Law 39 (2023): bans the sale, lease or rental in NYC of e-bikes not certified to UL 2849 (or equivalent) and batteries not certified to UL 2271, passed after the 2023 fire incidents.
• California SB 1271: UL 2849 / UL 2271 mandate operative 1 January 2026 for all e-bikes sold in California.
• Colorado HB 25-1197: UL 2849 / EN 15194 mandate effective 6 August 2025 for all lithium-ion e-bike batteries.

For apartment / condo / shared-workspace storage, the Roamer ST's UL certification is one of its biggest concrete advantages.

Hydraulic disc brakes with 180mm rotors, appropriately sized for the bike's mass + Class 3 speed. Front suspension fork is a basic spring fork. 7-speed Shimano drivetrain, the universal Amazon e-bike groupset. Front + rear lights wired to the battery; rear rack and full fenders standard.

Jasion warranty: 1 year on motor and battery, 6 months on frame and components. Shorter than Heybike (2 years frame/motor), Velotric (2 years), or Aventon (2 years). The Amazon return path is the safety net.

Buy this if you want a UL 2849-certified Class 3 step-through under $1,000, if you want hydraulic brakes and a bigger battery than the Heybike Cityscape 2.0 offers, or if you need a step-through frame and Class 3 speed for road commuting. Skip this if you want maximum battery capacity (528 Wh is smaller than the 720 Wh in the EB5 MAX or the Vivi ACE07), if you want torque-sensor pedal assist (Jasion is cadence-sensor across the catalog; the Vivi ACE01 lists a torque sensor, on a high-step fat-tire frame), or if 2-year warranty is non-negotiable.