ES1-G Electric Gravel Bike

The Ventum ES1-G is a performance-oriented electric gravel bike that takes the brand’s GS1 carbon gravel platform and adds a high-power Shimano EP801 system. That gives it a notably different brief from lightweight, low-assist e-gravel bikes: with 85Nm of torque, Class 3 assistance up to 28 mph, and a removable 504Wh battery integrated into the downtube, the ES1-G is built to cover ground quickly and handle steeper terrain with less compromise in speed. Its full carbon frame and fork, internal routing, flat-mount brakes, and UDH compatibility place it firmly in the modern premium e-gravel category rather than the adventure-touring end of the market.

What distinguishes the ES1-G is the way it combines a race-influenced gravel chassis with a full-power mid-drive system and Shimano’s electronic integration. Ventum pairs Ultegra Di2 shifters with an XT rear derailleur to access Shimano Auto Shift and Free Shift functions, an unusual but logical setup for an e-bike intended to smooth cadence management over variable terrain. Tire clearance up to 700x50c broadens its range beyond hardpack gravel, but the bike’s stated aggressive geometry suggests it is aimed more at riders who want a fast, assertive e-gravel bike for training, spirited mixed-surface riding, and high-speed commuting than a relaxed all-road machine.

$5,999
Ventum ES1-G Electric Gravel Bike
Build
Size

Inventory

Stack506mm
Reach399mm
Top tube559mm
Headtube length90mm
Standover height776mm
Seat tube length531mm

Fit and geometry

The ES1-G’s geometry is notably progressive for an e-gravel bike, with a long front center, relatively stretched reach, and size-specific head tube angles that steepen as sizes increase. Reach numbers run from 399mm in XS to 441mm in XL, while chainstays stay fixed at 435mm across the range. That points to a bike with stable weight distribution and a purposeful, forward riding position. The smaller sizes use especially slack front-end figures for gravel—69 degrees in XS and 69.5 degrees in S—paired with high trail numbers of 86mm and 82mm, which should calm steering and add confidence for smaller riders who might otherwise get twitchy handling from scaled-down frames. Larger sizes sharpen progressively to 72-72.5 degrees with trail dropping to 65mm and 62mm, keeping steering response from becoming overly slow.

A consistent 70mm bottom bracket drop and 72.5-degree seat tube angle across all sizes suggest predictable fit and handling throughout the range. Stack and reach figures are fairly aggressive rather than upright, particularly in the M (545/414) and L (589/432), reinforcing Ventum’s race-bred positioning. Combined with the 435mm rear center and wheelbases from 1049mm to 1091mm, the geometry should deliver a planted, high-speed feel with enough front-end stability for rough gravel, while still preserving the directness expected from a performance-focused drop-bar bike.

Full specs

Frameset

Frame

Ventum ES1-G Electric Gravel Bike Frame | Full carbon fiber construction | Internal cable routing | Flat mount disc brake | UDH

Fork

Ventum ES1-G Electric Gravel Bike Fork | Tapered carbon steerer | Internal brake routing | Flat mount disc brake | Carbon dropouts

Groupset

Shift levers

Shimano Ultegra Di2 | Electronic shifting | Hydraulic braking

Rear derailleur

Shimano Deore XT Di2 rear derailleur | 1x12 speed | Electronic shifting

Cassette

Shimano Deore XT | 10-51T

Chain

Shimano Deore XT | CN-M8100

Crankset

Shimano STEPS Hollowtech crank arms | 42T chainring

Bottom bracket

N/A

Front brake

Shiman Ultegra | Hydraulic

Rear brake

Shiman Ultegra | Hydraulic

Front rotor

Shimano XT Centerlock | 180mm

Rear rotor

Shimano XT Centerlock | 160mm

Wheelset

Front wheel

WTB Speedterra i23 front wheel | Tubeless, disc brake | Center Lock

Rear wheel

WTB Speedterra i23 rear wheel | Tubeless, disc brake | Center Lock | Shimano MicroSpline freehub

Front tire

WTB Venture | 700x50c

Rear tire

WTB Venture | 700x50c

Cockpit

Stem

FSA OS-98 stem | 90mm

Handlebars

FSA K-Wing AGX Handlebar | 420mm wide

Saddle

Fizik Argo R5 150mm

Seatpost

FSA SL-K SB20 Carbon Seat Post | 31.6mm

Builds

The ES1-G is offered in a single Electric Gravel Bike build at $5,999, which places it in the premium but not top-tier end of the carbon e-gravel market. The core of the value proposition is the drivetrain and motor package: Shimano’s EP801 drive unit with 85Nm of torque, a removable 504Wh battery, and a mixed Di2 setup using Ultegra shifters with an XT rear derailleur. That configuration is notable because it enables Shimano Auto Shift and Free Shift, features that make particular sense on an e-bike where maintaining cadence and managing shifts under load matter more than on a conventional gravel bike.

Beyond the drive system, the frame itself carries contemporary standards expected at this price, including a carbon frame and fork, internal cable routing, flat-mount disc compatibility, UDH, and clearance for 700x50c tires. With only one build available, buyers are effectively choosing into Ventum’s intended concept rather than sorting through multiple spec tiers: a fast, electronically integrated, full-power e-gravel bike with a strong emphasis on performance and system cohesion.

Electric Gravel Bike

Electric Gravel Bike

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