HKM-7918803 Fat Tire E-Bike Runs a 1500W Hub to a 20 mph Ceiling on 20 x 4.0 Tires With an 864Wh Pack and 7 Speeds

1500W · 864Wh · 20 mph · 20 x 4.0 · black or yellow · 7-speed · twin red coils · 136.7 lb · 330 lb

A Twenty Mph Ceiling and a Frame That Will Not Flex Under LoadBlack Steel With One Yellow Streak

A 20-inch fat bike with a 1500W hub, an 864Wh pack in the frame and a 20 mph speed ceiling, which is the number that decides where you can legally ride it. Twin red coil shocks, a sprung fork, mechanical discs and Shimano seven-speed gears. It weighs 136.7 lb and carries 330 lb, and it comes in black or in yellow. The frame wears a carbon-weave side panel in place of an engine cover, and the red springs on the rear shocks are the only colour that is not black.

The frame is a squared loop with a carbon-weave side panel standing in for an engine cover, a long bench and a round headlamp in a caged shell. Black is the default build and yellow is the loud one; either way the springs, the fork and the rims stay black, so the frame colour is the only statement.

At 136.7 lb it is one of the two heaviest bikes in this range, and that weight is what buys the 330 lb rating: the frame does not walk under a heavy rider, and the bike sits flat on a rough track instead of skittering. The cost is that it goes on a ramp, not a roof rack.

At a Glance

• 1500W Rear Hub — 48V system, single motor
• 48V 18Ah Pack — 864Wh behind the side panel
• 20 mph Ceiling — The number to check against local law
• 20 to 37 Miles — Listed range
• Shimano 7-Speed — Trigger shifter at the right grip
• Twin Red Coils — Rear shocks with visible springs
• Mechanical Discs — Front and rear
• 20 x 4.0 Tires — Knobby casing on spoked rims
• 136.7 lb — Heavy, and rated for it
• 330 lb Load — 150 kg rating
• Black or Yellow — Frame colour is the only choice
• Long Bench — Moped length, fixed

Squared Frame in Black or Yellow

The frame is a squared loop with a carbon-weave panel in the triangle and a long bench that runs back over the rear wheel. A round headlamp sits in a caged shell above the front mudguard, and the fork is a straight-leg unit with a brace across the crown.

The wheels are 20 x 4.0 knobbys on black spoked rims. Spokes can be trued with a key after a hard knock, and the wide casing carries a 136.7 lb bike over loose ground without the tyre sinking. Run them at 15 psi on pavement and 8 on sand.

The rear end runs two coil shocks with red springs and visible reservoirs, which is the detail that separates this from a hardtail. Brakes are mechanical cable discs at both ends with a barrel adjuster at the lever, and the drivetrain is a Shimano seven-speed derailleur with a trigger shifter.

• Frame: squared loop, black or yellow
• Battery: 48V 18Ah behind the panel
• Wheels: 20 in spoked, 4.0 knobby
• Fork: straight leg with a crown brace
• Rear: twin coil shocks, red springs
• Brakes: mechanical cable disc

Fitted as shipped: the caged headlamp, front and rear mudguards, the long bench, a kickstand and the pedals. The bars carry the throttle, the assist switch, the brake levers and a display, and the frame panel hides the controller and the charge port.

1500W Under a 20 mph Ceiling

The motor is a 48V 1500W rear hub, but the listed speed is 20 mph rather than the 30-plus some bikes in this group quote. That matters more than the wattage: 20 mph keeps the bike inside the Class 2 throttle limit in most states, which is the difference between a legal path bike and a private-ground toy.

The pack is 48V 18Ah, 864Wh, behind the side panel. The listed range is 20 to 37 miles: 37 is low assist on flat ground, 20 is throttle and hills. Charge it through the port on the frame panel, which keeps the bike where it is parked rather than the battery coming indoors.

Weight and rating belong together here. A 136.7 lb bike that carries 330 lb is built for an adult with a pack and it stays planted at speed. What it will not do is go home on pedal power alone, so plan the loop on the lower range figure and keep an eye on the battery bar.

Who It Fits and How It Rides

The bench is long and low and the bars are high, so it suits riders from about 5 ft 5 in to 6 ft 3 in, and heavier riders in particular because of the 330 lb rating. At 136.7 lb it is a two-person lift onto a truck bed, which is the practical limit on owning one.

On gravel and packed dirt it tracks straight and the red coils keep the bench level, and the fat casing floats over sand. On pavement the 20 mph ceiling keeps it civil, and the knobbys hum above 15 mph. It is a fire road and campground bike rather than a commuter.

• Fire roads and gravel tracks
• Campgrounds and private ground
• A heavy rider who needs the 330 lb rating
• Not for stairs a roof rack or tight storage

What's in the Box

Before the first ride: fit the front wheel and torque the axle, set the bars square to the fork, set the rear shock preload for your weight, bed the cable discs in with ten firm stops and charge the pack. Budget 40 to 60 minutes, and check every fastener after the first hour of riding.

Color and Finish

Two finishes: satin black, which is the whole bike in one colour, and a bright yellow frame with black springs, black fork and black rims. The side panel is carbon-weave black on both, and the only other colour is the red of the rear springs.

Touch-up paint is available in both frame colours. The wear points are the panel edges where a knee rubs them, the bench edges and the fork lowers where roost hits them.

Battery Care and Maintenance

Charge between 20 and 90 percent for everyday use and take it to full about once a month. The pack sits behind the frame panel rather than lifting out, so charge it where the bike is parked and keep that spot above freezing. If the bike will sit for a month, leave it around half charge.

Check tyre pressure before every ride at 15 psi on pavement and 8 on soft ground, and check the spokes and axle nuts after the first 50 miles. The cable discs need the barrel adjuster turned as the pads wear. Keep the chain oiled so the seven gears shift, and reset the shock preload if the rider changes.

Specifications

Frequently Asked Questions

Service and Policies

Coverage that lasts beyond the box. Orders ship free with a tracking number in 2 to 5 business days. From delivery, the product is protected for 180 days against manufacturing defects and transit damage, returnable within 30 days for a full refund, and covered by a 24-month parts-and-labor warranty on manufacturing defects. Four policies, one idea: ship it free, protect it for 180 days, take it back for 30, and stand behind it for two years.

HKM-7918803 · fat tire electric bike · 48V 1500W rear hub with a 20 mph listed ceiling and a Shimano 7-speed drivetrain · 48V 18Ah 864Wh pack behind a carbon-weave side panel · 20 to 37 miles listed range · mechanical cable disc brakes front and rear · straight-leg fork with twin red coil shocks at the rear · 20 x 4.0 knobby tires on black spoked rims · squared frame in satin black or yellow with a long bench · 136.7 lb with a 330 lb load rating · sized 5 ft 5 in to 6 ft 3 in · charger in the box · UL listed · built for fire roads, gravel and campgrounds rather than bike lanes · a 20 mph ceiling so it fits the Class 2 throttle limit in most states · twin red coil shocks and a long bench over the rear wheel · 330 lb rating so a heavy rider is not the limit