Brompton Electric G Line 20-Inch Folding Electric Bike
- Class 1
- Up to 400 Wh
- 41-60 mi claimed
- 251-300 lb max load
SVT Score, Upper
A 20-inch folding e-bike with hydraulic discs, integrated lights and a rack, US-tuned to 20 mph, heavier and bulkier than 16-inch models.
$4,950
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Usability
4.6 out of 10- Torque: 30 Nm reported by BikeRadar and a retailer listing, not printed by Brompton, not scored
Better on motorTern Vektron P10Bosch Performance Line mid-drive is rated 65 Nm of torque. $3,699Scores 4.0- Rotors: 140 mm front and 160 mm rear
- Sizes: small, medium and large at one price
- Searched: ACT Lab compliance directory (non-NRTL) Certipedia Intertek UL SGS TÜV SÜD CPSC Health Canada
- Record: ACT Lab compliance directory (non-NRTL), ANSI/CAN/UL 2849:2022 (sample test, e-Val certificate), Electric G Line - e-Motiq system; stock/model 'Electric G Line, Electric G Line - e-Motiq system', Brompton Bicycle
- Frame: seven years with registration, not scored
Strengths
- Hydraulic discs stop with confidence
- Rides like a full-size bike
- Wide tires handle gravel and potholes
- Assist runs to the full US class speed
- Integrated lights rack and fenders fitted
Drawbacks
- Heavy to carry up stairs
- Bulky when folded next to 16-inch models
- Small battery for longer rides
- Wiring can snag when folding
- Electric parts carry two years unless registered
A capable all-road folding e-bike, but heavy to carry far
Specs
- TypeFolding
- E-Bike ClassClass 1
- BatteryUp to 400 Wh
- MotorHub
- Top SpeedUp to 20 mph
- Claimed Range41-60 mi
- Weight41-55 lb
- Max Rider Load251-300 lb
- BrakesHydraulic disc
- SuspensionNone
- FoldingFolds
- CertificationsClaimed only
- Warranty2 Years
At a glance
- Three frame sizes
- 4-hour charge with 2A charger
- Tan-wall gravel tires
- Brompton Bicycle Inc names its address as Jericho, New York in the store terms of use.
- Brompton Bicycle Ltd of London designs and hand-builds the bikes.
- Brompton e-bikes are sold in the US by Brompton Bicycle Inc through its own store at us.brompton.com.
- Its store sells 16-inch and 20-inch folding e-bikes on one shared e-Motiq motor and battery.
- The bikes are also sold by a national outdoor retailer and by independent US dealers.
- REI is the only major US retailer that sells Brompton e-bikes as the seller, carrying the Electric C Line and Electric G Line (October 2026).
The Brompton Electric G Line (e-Motiq) is a steel folding e-bike with 20-inch wheels, a 4-speed derailleur, an aluminum fork and a 250 W rear hub motor with a torque sensor that Brompton says is US-tuned to assist up to 20 mph.
Its removable 345 Wh battery charges in about four hours with the included 2A charger, and Brompton claims 20 to 45 miles on the spec table and up to 50 miles in the page text.
It has Tektro hydraulic disc brakes with 140 mm front and 160 mm rear rotors and Schwalbe G-One All Round 54-406 tires that Brompton calls puncture-resistant. Brompton lists it from 42.9 lb with the battery and 34.6 lb without, rated for 286.6 lb including luggage.
It comes in small, medium and large and includes integrated lights, fenders, a roller rack, wide quick-release pedals, an essentials battery bag and a bell. The US store lists Forest Green in all three sizes at $4,950.00; Adventure Orange reads out of stock.
Compared in
Questions answered from our data
How much does an electric bike cost?The 331 electric bikes we list run from $750 to $12,500, with a median of $1,899.
Are electric bikes UL certified?105 of the 331 electric bikes we list carry a UL 2849 listing we could look up by model.
How far can an electric bike go?265 of the 331 electric bikes we list claim 41 miles or more on a charge, each on its maker's own basis.
Which electric bikes have a battery over 1,000 Wh?18 of the 331 electric bikes we list have a battery over 1,000 Wh, as their makers rate it.
