Freesky Swift Horse Ultra Review 2026: $1,599, 1,680 Wh

Full-suspension fat tire · one 4,000 W peak Bafang rear hub motor · 150 N·m · one 48 V 35 Ah LG pack, 1,680 Wh · 87–140 miles on pedal assist · 20 mph by default · 83 lb · 400 lb capacity · Freesky's rider range 5'3" to 6'8" · $1,599 · verified September 25, 2026

Quick Answer — The Freesky Swift Horse Ultra X-6E is a $1,599 full-suspension fat-tire e-bike with one 4,000 W peak Bafang rear hub motor, 150 N·m and a single 48 V 35 Ah pack, 1,680 Wh. For a 180 lb rider on flat pavement, a full charge computes to 96 miles at 15 mph on the throttle.

Hold 20 mph and the same charge lasts about 68 miles; pedal easily at 15 mph and it stretches to 158. Freesky rates it at 87 to 140 miles on pedal assist, and the range section works out your own ride from speed, climbing, load, air temperature and tires.

Freesky publishes 38 mph, while its FAQ caps its bikes at 20 mph by default and ties anything faster to "a license, license plates, and insurance"; the class section weighs that against the statutes.

What this review covers

What $1,599 buys · What it is · Will it fit you · The motor · The battery · How far it goes · Brakes and lights · Suspension and tires · Weight and load · The Mercer fit test · UL · Recalls · The class question · Where to ride it · Green and red flags · The verdict · Checklist · Buying it from us · FAQ · Limitations · The bottom line · References

How we verified this Freesky Swift Horse Ultra X-6E review

Every figure here was read on September 25, 2026 from Freesky's Swift Horse Ultra X-6E product page, its product record, the X-6E manual that page links, the two UL certificates it links, our listing or the statutes quoted in the class section. The range and fit figures are computed, and each section's formula names its inputs and their sources.

This review is specification-verified: each number is Freesky's, a statute's, or arithmetic shown on this page, and the range model reproduces the published benchmarks it rests on. We sell the Swift Horse Ultra, so weigh the red flags as carefully as the green ones.

Written by Milad Ghobadibeygvand, BScN (Western University, 2014). Corrections: support@redtailebikes.com.

What $1,599 buys

Read September 25, 2026 from Freesky's product page and its product record. The charge time comes from the comparison chart on that page, the headlight rating from the record's feature list, and the charger, keys and tools from the box list in the manual.

A full-suspension fat-tire bike with one Bafang hub motor

Freesky's own label for the Swift Horse Ultra X-6E is a "Premium all-terrain electric fat tire ebike". Behind that line are a full-suspension mountain-bike frame, 26 × 4-inch tires, one Bafang motor inside the rear wheel and one removable 35 Ah pack along the down tube.

From the front three-quarter, drive side: the round headlight on the fork, the 120 mm fork and the 26 × 4 CST tire.

The motor's maker is the headline. In the comparison chart on Freesky's page, this is the one bike of seven whose motor row names Bafang: "4000W Peak BAFANG Brushless Motor". Freesky's hunting-bike guide of September 8, 2026 files it as "Best for Long-Range Single-Motor Performance" and describes "a 4000W peak BAFANG motor with up to 150 N·m of torque and a 48V 35Ah LG battery."

From behind: the rack, the hub motor turning inside the rear wheel with the freewheel on its side, the derailleur, and the shock tucked under the top tube.

One 35 Ah pack does the work here, at 48 V, and Freesky prints its total as "1680Wh LG Battery". Freesky's listing for the bike, created on June 18, 2024, has carried more than one build, and its reviews are labeled by build; every figure here comes from that listing as it read on September 25, 2026.

Will the Swift Horse Ultra fit you?

The saddle reaches the height the fit formula asks for on 100 of every 100 riders at 5'2", 99 of 100 at 5'4" and 84 of 100 at 5'6", then on 53 of 100 at 5'8" and 15 of 100 at 5'10"; Freesky's published window runs from 5'3" to 6'8".

The median rider leans 12 to 17 degrees from upright, and with the back fully relaxed the hands carry 14 to 17 percent of body weight.

The model puts the 6,068 bodies the US Army measured for its 2012 survey on Freesky's own geometry, with each saddle set at 109% of inseam.

To place yourself on this frame:

1. Measure your inseam in socks. Stand against a wall, draw a hardcover book up firmly between your legs where a saddle would sit, and measure from the floor to its top edge.
2. Find your row in the tables below and check that your inseam falls inside its range; above a 32.7-inch inseam, the saddle rides at the top of its post.
3. Fine-tune the saddle on delivery with the knee and heel checks at the end of this section.

Freesky's page prints one frame, one rider window, one inseam range and two different standover heights; its drawing gives a third.

Freesky's drawing at the scale of its published 48.5-inch wheelbase. The total length, the seat-tube angle and the reach agree with the tables to within 3 percent; the highest-seat, lowest-seat, total-height, standover and wheel lines all measure longer than their labels.

Will the saddle go high enough for me?

For most riders up to 5'6"; at 5'8" about half, and from 5'10" most, reach the top of the post before the formula's height. The formula sets the saddle 109% of inseam above the pedal axle (Peveler et al., 2005), with a published range reaching down to 106% (Ferrer-Roca et al., 2012).

Turning that into a height off the floor runs through the 12.6-inch crank axle, the 170 mm cranks Freesky lists for the Swift Horse and its 73.5° seat tube.

Floor-to-saddle height for the typical rider of each height, and the count out of 100 at that height whose 109% and 106% heights fall within Freesky's 33.9 to 40.5 inches of seat travel; Army survey bodies, both sexes.

Freesky prints inseams up to 35 inches; the post's top meets 109% of inseam at 32.7 inches, and 106% at 33.7. Past that, the saddle stays at its highest and your knee bends more at the bottom of the stroke than the formula would set it.

The short end turns on two lowest-seat figures. At the 37.6 inches Freesky's drawing marks, the lowest saddle suits a 109% inseam of 30.0 inches, above the 27-inch minimum Freesky prints; at the listed 33.9 inches it would suit 26.4. Near a 30-inch inseam, measure your saddle against both.

Can I put a foot down at a stop?

It depends which of Freesky's figures matches the frame: for 95 of 100 riders at each height, the Size & Fit table's 21 inches clears by 7.0 inches or more in every row, the Geometry table's 28 inches from 5'4" up, and the 30.0 inches its drawing measures from 5'6" up.

There is no step-through here; you swing a leg over the top tube to get on. Until the frame is under you, plan on the highest figure.

Barefoot inseam minus each figure: 21 inches from Freesky's Size & Fit table, 28 from its Geometry table, 30.0 measured on its drawing at the wheelbase scale. Each cell is the clearance 95 of 100 riders at that height have or exceed, with a minus sign where the tube sits higher than that inseam.

Will I feel cramped, or stretched?

A little forward: the median rider leans 12 to 17 degrees from upright, because the grips sit 29.2 to 32.0 inches above the crank axle and 15.1 to 18.4 inches ahead of it.

In a 20-rider study, recreational cyclists rated the most upright of three trunk positions the most comfortable (Priego Quesada et al., 2017). Each angle is the least lean that lets a straight arm meet the grip from the sit-bone position, computed from that body's measured torso and arm.

Trunk lean from vertical for the middle rider of each height; the spread covers where the sit bones rest on the saddle and the length of the grip on Freesky's drawing.

How much weight goes through my wrists?

Up to 14 to 17 percent of your body weight with a fully relaxed back, close to what road racers put on their bars. In a lab study, 10 road racers pedaling with their hands on the hoods put 15% of their weight through the bars (Carahalios, 2015); on the Swift Horse Ultra's lower grips, the median rider's relaxed-back ceiling lands within two points of that figure at every height in the table.

Leaning further forward shifts the load onto the heel of the hand, over the ulnar nerve, and in 36 riders that pressure was highest in the most stretched-out hand position (Slane et al., 2011). Padded gloves cut the palm pressure by 10 to 28% in the same study, which makes them worth having for long days on this bike.

Ceiling on the hands with the back relaxed, from each body's segment weights (Clauser et al., 1969); the spread runs across saddle and grip positions, at the survey's median weight for each height.

How do I set the saddle when it arrives?

Aim for a knee that still bends 25 to 35 degrees with the pedal at the bottom (Peveler et al., 2007). The X-6E manual words the same check for the ball of the foot on the low pedal: your leg "should be almost fully extended(not locked out) with a slight bend at the knee."

The heel method, with the heel on the low pedal and the saddle raised until that leg just straightens, put 70% of 19 cyclists in range, more than either inseam formula did (Peveler et al., 2005). The same manual draws a hard line on the post: "DO NOT raise the seatpost beyond the minimum insertion marking etched into the seatpost tube."

How we computed fit

Saddle height is 1.09 × inseam from the pedal axle; lean is the smallest trunk angle at which a straight arm reaches the grip; hand load is the upper body's weight times its lean, divided by the reach to the grip.

Take a 5'8" rider with the median 32.6-inch inseam: the formula needs 35.6 inches from the pedal, which is 28.9 inches from the crank axle (88.3% of inseam gives 28.8), a floor-to-saddle height of 40.4 inches, one tenth of an inch under the 40.5-inch top of the post.

Before anything was read off the drawing, it was held against Freesky's own figures.

Scaled from the published 48.5-inch wheelbase, axle center to axle center. Five labels differ from the lines they mark, so the model takes the crank axle, seatpost and grips from the drawing, keeps Freesky's listed seat range, and prints every standover figure.

One 4,000 W peak Bafang rear hub motor and 150 N·m

Freesky's page puts it this way: "With 150 N·m of torque, it effortlessly conquers any terrain—perfect for commuting, weekend rides, and off-road adventures." Its specification lists a "4000W Peak BAFANG Brushless Motor", and a peak figure is the brief burst a motor can give; what it holds for long stretches is its continuous rating, a figure the class section returns to.

Freesky's cutaway of the rear hub motor, drawn inside the wheel with the freewheel beside it, on a Blue-gray frame.

The hub turns with the wheel, so shifting gears changes your cadence and leaves the motor's speed alone. At a given road speed, the battery answers to how hard you pedal, and the effort table puts a price on it.

Help arrives through a cadence sensor: once the cranks turn, the motor adds the level you choose from 0 to 5, and the thumb throttle moves the bike without any pedaling. The first ride the manual sets out is a gentle one: flat ground, "a low gear (1 or 2)", and pedal assist "set to level 0 or 1".

The black frame's rear drive: the hub motor behind the seven-cog freewheel, the derailleur, and the rotor on the far side.

One 48 V 35 Ah pack, 1,680 Wh

48 V × 35 Ah is 1,680 watt-hours, the figure Freesky's page prints beside the pack, "1680Wh LG Battery". The pack's own certificate lists 47.19 V nominal and 35 Ah, which multiplies to 1,651.7 Wh; the range tables use Freesky's 1,680.

The 35 Ah pack along the down tube, on a Blue-gray frame; Freesky names this picture for the Ultra's 35 Ah LG pack.

The pack comes off with its key. Under "Remove the battery", the manual has you turn the key counterclockwise to open the battery lock and hold the battery in one hand, and it allows charging "With the battery on or off the bike", so the pack can charge indoors while the bike stays in the garage.

Charge it in the dry, at 50 to 77 °F. The manual says the bike "is not intended to be used and stored" below 32 °F or above 104 °F, allows charging only inside that same span, and asks you to "Charge and store bike and battery in a dry location, between 50 °F – 77 °F".

Freesky's chart gives 8–10 hours on the 3 A charger in the box; for a ride that will not need all 1,680 Wh, Freesky's summer charging guide notes that "charging to 80–90% can reduce thermal and chemical stress."

How far the Swift Horse Ultra goes on one charge

On flat pavement, a 180 lb rider gets about 96 miles from a full charge at 15 mph on the throttle, 68 at 20 mph, and 158 at 15 mph with easy pedaling. Climb an 8% grade at 10 mph on the throttle and the same charge lasts 14 miles.

Working out your own figure takes three steps:

1. Pick your speed and your effort in the first two tables.
2. Budget 199 to 283 Wh of the 1,680 for every 1,000 feet of climbing (10 mph on the throttle, 4 to 10% grades), or 164 to 243 if you pedal easily (the hills table).
3. Adjust for your load and the air temperature, then plan on 80% of the result.

Each table computes one steady ride at a time from Freesky's specifications, Bafang's published figures for a comparable 48 V geared hub motor, drum readings for ten 26 × 4.00 fat tires, the bike's own tire size, and a cycling-power model checked on a real road. The last subsection shows the formula and carries one ride through it.

Does riding faster cut range? Miles at each speed

On the flat, speed is the first thing to settle: on the throttle, a full charge runs 133 miles at 10 mph and 40 at 28. From 15 mph to 20, a full charge drops from 96 miles to 68, because the power the air takes rises with the cube of your speed: 20 mph needs about 2.4 times the air power of 15, which is (20 ÷ 15)³.

Throttle only, level pavement, a 180 lb rider at 77 °F. The right-hand column is an 80% charge, where Freesky's summer charging guide suggests stopping when the whole pack will not be needed. The rows past 20 mph price speeds above the default limit, which the class section takes up.

Light pedaling stretches a charge a long way on the flat: 75 W from your legs at 15 mph takes a full charge from 96 miles to 158. Easy pedaling in these tables is 75 W and steady pedaling 150 W. On its own, with the motor idle, 75 W would carry this bike at about 9.0 mph on level ground and 150 W at about 13.2, so choose the column you could hold without help.

Miles from a full charge on level pavement, a 180 lb rider; easy pedaling at 15 mph draws 10.6 Wh a mile where the throttle draws 17.5. In the 282-, 367- and 163-mile cells your legs push harder than the motor, so those three lean most on the model's weakest part, its motor losses at light load (Limitations item 5). "Legs alone" means 150 W holds 12 mph with the motor idle.

Your assist level decides how much the controller adds while you pedal and changes nothing else in these sums, so read the row for the speed you hold and the effort you give. The manual's own range tips run the same way: "Ride at a lower PAS level" and "Use lower PAS levels and pedal when climbing hills."

Which gear saves battery? On a hub motor, your effort does

Change gear for your knees and pedal for the battery. Since the hub motor spins with the rear wheel in every gear, a shift alters your cadence and leaves the motor's load where it was. At a set speed and grade, the draw falls as your push rises:

Watt-hours drawn from the pack per mile, a 180 lb rider at 77 °F; easy pedaling is 75 W from you and steady pedaling 150 W.

On an 8% grade at 10 mph, the throttle alone takes 119.2 Wh a mile; easy pedaling lowers it to 93.6 and steady pedaling to 71.2. Every watt at the pedals is one the motor does not have to supply, together with the heat the motor and the pack would have lost producing it.

Keep the gears for a comfortable cadence, low ones for starts and climbs as the manual suggests for a first ride, and let your legs do the saving.

Does going uphill drain the battery faster?

Much faster: at 10 mph on the throttle up 4 to 10% grades, each 1,000 feet you climb costs 199 to 283 Wh beyond the same distance on the level, or 164 to 243 with easy pedaling. Raising you and the bike accounts for 35 to 50% of the throttle figure, and the motor and the pack lose the remainder, a share that grows as the road steepens.

A 180 lb rider on the 83 lb Swift Horse Ultra weighs 263 lb together, and lifting 263 lb through 1,000 feet takes 99 Wh at the wheel.

Up an 8% grade at 10 mph on the throttle, the pack pays 253 Wh for each 1,000 feet, so the full 1,680 Wh would climb about 6,638 feet with nothing saved for the flat. The model gives no credit for descents; since coasting downhill costs less than the same distance on the level, a budget built from these rows leaves some in hand.

10 mph, a 180 lb rider; the right-hand column adds 75 W of easy pedaling. The model holds the motor to a comparable motor's rated 1,000 W, so it prices a climb's energy; how fast the Swift Horse Ultra holds a grade depends on a motor Freesky rates at 4,000 W peak, so no hold speed is printed.

Price a hilly ride as level miles plus climbing. Thirty level miles at 15 mph on the throttle use about 524 Wh, and 2,000 feet of 8% climbing adds about 506, near 1,030 Wh of the 1,680 in all. Wind, stops and starts come on top, because every mile in the model is ridden at an even pace.

Does rider weight affect range?

A heavier load costs a little on the flat and a lot on a hill. More weight adds to the work of the tires and the grade and nothing to the air's share, so the gap widens as the road tilts up.

Everyone and everything on the bike, with its own 83 lb added in every row because the motor carries that too; throttle only. The 400 lb row is Freesky's full load capacity, which Freesky's own guidance counts as rider plus cargo.

Going from 180 lb to 300 lb takes 17 miles off the level 15 mph ride, from 96 to 79, and cuts the 8% climb from 14 miles to 8. With the full 400 lb aboard, the level 15 mph ride still reaches about 68 miles, while the 8% climb shrinks to 5, since on a grade most of the power at the wheel goes into lifting.

Does cold weather drain the battery?

Yes, and each colder row costs more. The easy-pedaling 15 mph ride that covers 158 miles at 77 °F comes to about 117 at 32 °F. The manual rules out riding, storing and charging below 32 °F, so treat the 14 °F row as a reason to leave the bike in.

Level pavement, a 180 lb rider. The central figures come from McMaster University's LG HG2 cell data, recomputed at a 0.5C discharge; the lab measured 77, 50, 32 and 14 °F, the other rows are interpolated, and the cells are taken to be at air temperature.

Brackets mark the spread between published cell data sets. The low end of each is the least capacity Samsung's data sheets print at that temperature for a cell drained at one to four times its capacity per hour (the 25R and 30Q at 32 °F, the 35E at 14 °F); the high end is the most energy Casado and colleagues recorded in 2025 at a slower rate.

Three losses stack up at freezing. The cells return about 89% of the energy they give at 77 °F (80 to 93% across the sources), and the air is about 9% denser, by the gas law in the U.S. Standard Atmosphere.

The third is cold rubber: the model raises rolling resistance 0.5% for each °F below 77 °F (0.9% per °C) and lowers it at the same rate above, between Rothhämel's fit for a 42 mm tire and Bicycle Rolling Resistance's road-tire average, and holds the 41 °F value below 41 °F.

On a 95 °F day the model comes out slightly ahead of 77 °F, since warm tires and thin air save more than the cells lose.

Do fat tires cut range? Tires and riding position

On level ground your tire matters more to range than how you sit. Bicycle Rolling Resistance's drum measured ten 26 × 4.00 fat tires, this bike's size, at 23.2 to 42.1 W at 12 psi, 18 mph and a 94 lb load. It has no reading for the CST BFT printed on the Swift Horse Ultra's tires in Freesky's pictures, so the model takes the middle of the ten, a coefficient of 0.0105.

Full-charge miles on level pavement, a 180 lb rider. Of the ten, Schwalbe's Jumbo Jim LiteSkin rolled easiest and Kenda's Juggernaut Pro hardest, at 0.01262 on the site.

Keep the tires in the manual's range, "Freesky recommends 16-20 PSI for the stock tires", firmer than the drum's 12 psi. Sand, dirt and gravel have no drum reading at all; send us a route and we will run the trail ride through the model.

Posture counts for more as speed climbs. Tengattini and Bigazzi recorded 0.603 m² of drag area for 90 everyday mountain-bike riders, the value used here for this mountain-bike frame, and 0.640 m² for 37 upright cruiser riders, which would bring the 20 mph throttle ride from 68 miles down to 65.

Freesky's 87 to 140 miles, matched to real rides

Freesky's band of 87 to 140 miles on pedal assist spans a broad set of steady rides. The manual states plainly what a published range is: "The listed range and top speed of the bike are estimates, not guarantees of performance."

• 140 miles leaves 12.0 Wh a mile: about 9.1 mph on the throttle, 15.9 mph with easy pedaling, or 18.9 with steady pedaling, on level pavement.
• 87 miles leaves 19.3 Wh a mile: about 16.5 mph on the throttle, 20.0 with easy pedaling, or 22.3 with steady pedaling.

The top of Freesky's band therefore fits unhurried rides with some pedaling, and the bottom fits throttle riding in the mid-teens or easy pedaling at the 20 mph default. The model's 15 mph throttle ride, 96 miles, falls inside the band, and easy pedaling at 15 mph, 158 miles, runs past its top.

Owners on Freesky's page describe partial rides, in their own words. One who works "15 miles away from home" wrote on June 24, 2026: "I can ride back and forth on a full charge and speed and still have 5 bars left on the display." Another, on June 29, 2026, had put "70km in" over a few days with the battery still showing "5/5 bar".

Plan from 80% of any figure here. That is where Freesky's charging guide suggests ending a charge when a ride will not need the full pack, and it leaves 20% in the pack as a reserve. At 15 mph on the throttle, an 80% charge covers 77 of the full 96 miles.

How every figure here is worked out

A steady speed needs a steady flow of power at the rear wheel. Martin and colleagues' 1998 model, validated on an open road, gives that power in a single line for a constant speed in still air:

Power at the wheel = v × [ m × g × (Crr × cos θ + sin θ) + ½ × ρ × CdA × v² ]

In it, v is speed, m the combined mass of rider, cargo and bike, g gravity, θ the angle of the slope, Crr the tires' rolling resistance (0.0105 means a drag of 1.05% of the weight on the tires), ρ the density of the air and CdA the drag area, a measure of how much air the rider shoves aside.

The first bracketed term covers the tires and the grade and the second the air; once multiplied by v, the air term rises with the cube of the speed.

Between the wheel and the battery sit four steps:

1. Your pedaling reaches the rear wheel through the chain at 97.7% efficiency, the figure Martin and colleagues used, and the motor supplies the balance.
2. The rear hub motor does all of the motor's pushing, spinning with the wheel.
3. The motor follows a comparable motor's published figures. Bafang's 2021 OEM workbook lists its RM G0H0, a 48 V geared hub, at an n0 of 510 rpm, an nT of 426 rpm, a rated 1,000 W and an efficiency of "≥ 80" percent. Taken as the no-load and rated speeds, those come to 41.9 and 35.0 mph on Freesky's 27.6-inch wheel; the modeled motor tops out at 29.7 mph on the flat, so no row here goes past 28 mph. The model uses 80% at the rated point and lets efficiency drop at lighter loads.
4. The pack loses a little energy internally, at the battery efficiency Arango, Lopez and Ceren measured on a 48 V pack.

From there, watt-hours per mile = battery watts ÷ mph, and miles = 1,680 Wh × the share of the pack's energy left at that temperature ÷ watt-hours per mile.

A worked ride: 15 mph on level pavement on the throttle, 180 lb aboard. The tires take 82.7 W and the air 107.6 W, so the rear wheel needs 190.3 W.

At 15 mph the 27.6-inch wheel turns 183 rpm. In the motor model (0.899 N·m of torque per amp, a 0.304 Ω winding and a 1.10 A no-load current, each worked out from Bafang's published figures), the motor makes 10.0 N·m on 12.2 A at 75% efficiency, below its 80% because the load is light, and draws 254.2 W.

Adding the pack's own losses, the battery supplies 262.0 W: 17.47 Wh a mile at 15 mph, and 1,680 ÷ 17.47 comes to about 96.2 miles, or 76.9 from an 80% charge.

Two published benchmarks, recomputed. Both halves of the model land on the figures their sources print:

The worked example in Martin and colleagues' Appendix I (8.36 m/s ground speed, a 90 kg system, a 0.3% grade) and the RM G0H0's rated point in Bafang's workbook, each recomputed by the model's self-test.

Brakes and lights

Freesky specifies "180MM 4-piston Hydraulic Brakes" on both wheels, stopping an 83 lb bike rated to carry 400 lb. The manual is blunt about using both: "Relying only on the rear brake will significantly increase your stopping distance."

Up front, the four-piston caliper on the fork leg, clamping the rotor.

The product record lists an "800 Lumen LED Headlight", and the page describes a turn-signal system "Integrated into the handlebars" that works "with a simple press of a button."

The tail light, set into the end of the rear rack.

The LCD, in Freesky's words, "shows 5 PAS levels, headlight status, speed, battery level, and mileage". To switch the bike on, the manual has you turn on the battery first and then use the NFC swipe or the power button and the code the manual prints.

A 120 mm fork, a 150 mm air shock and 26 × 4 tires

Freesky specifies a "120 mm Oil-Sprung Front Fork" and a "150 mm Air Rear Shock", and writes that the pair "work together to absorb impacts and smooth out vibrations, delivering superior comfort, stability, and control on every ride."

Freesky's picture of both ends: the rear swingarm with the air shock at its top, and the fork beside the headlight.

On the black frame, the rear shock sits between the frame and the rear linkage.

The tires are 26 × 4" fat tires, run at 16 to 20 psi per the manual, firmer than the 12 psi in the tire table. Around them sit a Shimano 7-speed derailleur, a KMC chain, an "Upgraded 6061 Aluminum" frame and an adjustable heavy-duty aluminum kickstand.

83 pounds and a 400-pound capacity

Freesky lists 83 lb for the Swift Horse Ultra, in its specification and again in its comparison chart, with a 400 lb load capacity.

The 400 lb is for the rider and whatever the bike carries; the 83 lb bike sits outside it. Freesky's hunting-bike guide spells it out: "Remember that total payload includes the rider and cargo." A 230 lb rider carrying 50 lb on the rack and in a pack totals 280 lb, which leaves 120 lb to spare.

Size any hitch rack, lift or stair plan to the 83 lb Freesky lists plus whatever you carry on the bike, and to the 78 by 42.6 inches it gives for the length and height.

The Mercer fit test

Every review we publish puts the bike in front of the same seven people, the Mercers, so every machine answers the same fit questions (meet the Mercers). Each verdict below rests on a figure Freesky publishes (the height range, the seat heights, the standover figures, the weight, the load capacity) or the age line in the manual, or on the fit tables computed from them.

Frank and Jack show where the Swift Horse Ultra divides a family. Both are inside Freesky's window, and both ride the saddle at its top with more knee bend than the formula asks, while Ruth, Dana and Maya, from 5'5" to 5'7", get the formula height on most bodies their size.

Is it UL certified?

Yes: Freesky links a UL 2849 certificate for the X-6E and a UL 2271 certificate for its 35 Ah pack. Both come from TÜV SÜD America, and Freesky's page badges them "UL2849 Certified by TÜV" and "UL2271 Certified by TÜV".

Both read September 25, 2026 from the PDFs linked on the Swift Horse Ultra page; each names GuangZhou Yansan Science & Technology Co., Ltd. as the holder.

UL 2849 covers the whole electrical system; Freesky's own summary says it spans "batteries, motors, controllers, and wiring". The UL 2849 certificate also lists a battery charger with a 54.6 V DC, 3.0 A output, the rating of the 3 A charger Freesky specifies. If a landlord, a building manager or an insurer asks for the paperwork, email us and we will get it from Freesky in writing.

Has it been recalled?

No. On September 25, 2026 we searched the Consumer Product Safety Commission's recall database, reading every field of a 623-record corpus built from bicycle, e-bike, battery and scooter terms and querying the title, description, product-name and manufacturer fields directly for Freesky. No record names Freesky, Yansan, the X-6E or the Swift Horse.

The search had to find recalls known to exist before its empty answer counted, and it did: Ancheer 1, Specialized 49, Trek 34.

The class question: 20 mph by default, 38 mph published

Settle this before you order, because Freesky describes two speeds for the Swift Horse Ultra. Its product page promises "speeds of up to 38 MPH in both throttle and pedal-assist modes", and the product record's feature list reads "38 MPH by Pedal Assist & Throttle". Lower on the same page, the FAQ says:

All Freesky eBikes are limited to a maximum speed of 32 km/h (20 mph) by default, which complies with local e-bike regulations. If you wish to exceed this speed, you will need to obtain a license, license plates, and insurance for your eBike.

That makes two machines in one carton: the Swift Horse Ultra as delivered, helping up to 20 mph, and the 38 mph machine on the spec sheet, which Freesky's FAQ links to a license, plates and insurance.

California Vehicle Code § 312.5(a), read on September 25, 2026, defines an electric bicycle as a bicycle "equipped with fully operable pedals and an electric motor that does not exceed 750 watts of power".

The same section sets the class lines: a class 2 bicycle's motor "is not capable of providing assistance when the bicycle reaches the speed of 20 miles per hour", and a class 3 bicycle assists "only when the rider is pedaling" and "ceases to provide assistance when the bicycle reaches the speed of 28 miles per hour".

Federally, 15 U.S.C. § 2085(b) describes a low-speed electric bicycle as "a two- or three-wheeled vehicle with fully operable pedals and an electric motor of less than 750 watts (1 h.p.), whose maximum speed on a paved level surface, when powered solely by such a motor while ridden by an operator who weighs 170 pounds, is less than 20 mph."

Sources: § 312.5(a)(2) and (a)(3), Freesky's product page and product record, read September 25, 2026.

Ask for the continuous motor rating in writing. Freesky's figure, "4000W Peak", is a peak. California's text reads "does not exceed 750 watts of power" and the federal one "less than 750 watts", and neither says whether it means a peak or a continuous figure.

Wherever a watt line applies to you, email us and we will get the continuous rating from Freesky in writing before you order. Our 50-state e-bike law atlas prints each state's definition, and the manual points the same way: "contact local or state authorities to learn more about the electric bike rules surrounding e-bike legislation near you."

Check your insurance too. The manual cautions that "your insurance policies may not provide coverage for accidents involving Freeksy eBikes" and tells you to "contact your insurance company or agent" before relying on them.

Where you can ride it

Off pavement, whoever manages the land decides whether the Swift Horse Ultra may go there, and federal managers begin from the e-bike classes, so both the 20 mph default and the watt line matter.

On National Forest land, the Forest Service's final e-bike directives of March 31, 2022 "provide for managing all classes of e-bikes as motor vehicles and require local-level decision-making and environmental analysis to allow use of e-bikes on non-motorized trails", in the words of its notice at 87 FR 41278.

Where a Ranger District has issued a motor vehicle use map, 36 CFR 261.13 prohibits operating a motor vehicle "other than in accordance with those designations".

On Bureau of Land Management land, 43 CFR 8340.0-5 defines the three classes around "an electric motor of not more than 750 watts (1 h.p.)" and treats an e-bike as a non-motorized bicycle only where "the authorized officer has expressly determined" it.

Four kinds of ground and four documents; a spec sheet settles none of them.

On a National Forest, 36 CFR 261.1b sets the price of breaking the part's prohibitions at "imprisonment of not more than six months or a fine in accordance with the applicable provisions of 18 U.S.C. 3571 or both". Our public-land e-bike guide takes the agencies one by one.

On a slope like this, the land manager's rule is the one that counts; in this picture of Freesky's the rack and mudguards are off.

Green flags / Red flags

Green flags

• A named Bafang motor: "4000W Peak BAFANG", 150 N·m, driving the rear wheel.
• 1,680 Wh in one removable pack, good for a computed 96 miles at 15 mph on the throttle for a 180 lb rider, or 158 with easy pedaling.
• Full suspension: a 120 mm oil-sprung fork and a 150 mm air rear shock.
• Four-piston hydraulic brakes at both wheels, on 180 mm rotors.
• Lights and turn signals: an 800-lumen headlight, a tail light and signals switched from the handlebar.
• Published UL certificates: UL 2849 for the X-6E and UL 2271 for its 35 Ah pack.
• A rack and mudguards in the box, with a 400 lb load capacity for rider and cargo.
• The saddle reaches most riders from 5'2" to 5'6": 100, 99 and 84 of 100 at 5'2", 5'4" and 5'6".

Red flags

These are about fit: who the Swift Horse Ultra is wrong for, and where to go instead.

• Wrong if you will be carrying it up stairs every day. At 83 lb as Freesky lists it, steps and hitch racks may need two people; email us the stairs or the rack and we will point you to a lighter bike on our shelf.
• Wrong if your inseam runs past 32.7 inches and you want the saddle at full leg extension. That is where the 40.5-inch top of the post meets the fit formula; find your row in the fit tables before you order.
• Wrong if you are near 5'3" and need a low top tube at a stop. There is no step-through, and the standover table leaves little or no clearance from 5'2" to 5'4" on the higher figures; send us your height and inseam and we will find a lower frame on our shelf.
• Wrong if you want to sit bolt upright with little weight on your hands. The median rider leans 12 to 17 degrees here; email us and we will suggest a more upright bike from our range.
• Wrong for short trips on flat ground. A 1,680 Wh pack on a full-suspension frame is built for distance and rough ground; our hub-drive picks match lighter single-motor bikes to short commutes.
• Wrong below the age of 18. The manual sets 18 as the minimum age to ride it; our 50-state law atlas lists each state's age rules, and we can point a teenager to a bike that fits.
• Wrong if you plan to ride public roads faster than 20 mph without a license. Past 20 mph Freesky's FAQ calls for a license, plates and insurance; email us and we will suggest a bike that stays inside your state's classes.
• Wrong if you want a motor in each wheel for loose ground. The Swift Horse Ultra drives the rear wheel only; our dual-motor guide sets out bikes that drive both.
• Wrong if you want the assist to follow how hard you push. A cadence sensor answers the cranks turning, not the force on them; our e-bike motor guide explains both kinds of sensor, and we can suggest a torque-sensing bike from our range.
• Wrong for trails that admit Class 1 bikes only. Its throttle keeps it off them; our public-land guide quotes each agency's rule, and we will look up your trail with you.

Buy it if / Buy something else if

Buy it if you want a Bafang-driven full-suspension fat-tire bike that covers a computed 96 miles at 15 mph on the throttle from one pack, and you ride dirt roads, gravel, rough pavement, trails open to e-bikes like this one, or your own land.

It also asks that you be 18 or older and 5'3" or taller, with the saddle at its 40.5-inch top if your inseam runs past 32.7 inches, and that you can keep an 83 lb bike dry and charged at 50 to 77 °F.

For $1,599 you get a 4,000 W peak Bafang rear hub motor, a removable 1,680 Wh pack, full suspension, four-piston hydraulic brakes, lights and turn signals, a rear rack and mudguards. Shop Pay's sample plan on our listing is $144.32 a month for 12 months at 15% APR, $1,731.84 in total, subject to an eligibility check.

Owners on Freesky's page rated the bike 4.9 out of 5 across 144 reviews as of September 25, 2026, reviews that span the builds the page has carried. Among those written about this Ultra build, one owner wrote on July 7, 2026: "I'm a 70 year old and I ride just about every day. I get a lot of enjoyment out of it." Another, on September 14, 2026, called it "an incredible bike".

Buy something else if your trips are short and flat, where our hub-drive picks fit a lighter bike to the job; if you want a motor in each wheel for loose ground, which our dual-motor guide covers; or if your trails allow Class 1 bikes only, in which case email us the trail system and we will match a bike to its rule. Every review we have published sits on our e-bike reviews hub.

Before you buy: the checklist

Ten checks before you spend $1,599; the first three tell you whether the Swift Horse Ultra is yours to ride at all.

1. Check the rules where you will ride: your state's e-bike definition for roads and paths, the land manager's for trails.
2. Make sure the rider is at least 18, the manual's minimum.
3. Get the continuous motor rating from us in writing if a watt line applies where you ride.
4. Measure your inseam and find your row in the fit tables; past 32.7 inches, the saddle sits at its top.
5. Check your inseam against all three standover figures, 21, 28 and 30.0 inches, in the standover table.
6. Total the rider and everything they carry and keep it at 400 lb or less; the 83 lb bike does not count toward it.
7. Plan the storage and the lift for an 83 lb, 78-inch bike, plus whatever you carry on it.
8. Find your ride in the range tables, plan on 80% of it, and budget your climbing.
9. Choose a charging spot that stays dry and between 50 and 77 °F, and allow Freesky's 8–10 hours.
10. Read the class section before you ride faster than 20 mph anywhere.

Buying it from us

Why buy the Swift Horse Ultra from Redtail

Our listing priced the Swift Horse Ultra at $1,599 in Black, Green and Blue-gray on September 25, 2026, with $2,449 shown as the regular price. Our part begins the day the order ships.

Changing your mind works differently: an unopened bike still sealed in its factory packaging, requested within 72 hours of delivery, carries a 15% restocking fee plus return shipping, and canceling an order carries a 3% transaction fee. That is why we would rather answer your fit, range and trail questions before the order goes in.

Frequently asked questions

How far can the Freesky Swift Horse Ultra go on one charge?

Freesky publishes 87 to 140 miles on pedal assist. Computed for a 180 lb rider on flat pavement, a full charge covers about 96 miles at 15 mph on the throttle, 68 at 20 and 158 at 15 with easy pedaling. At 10 mph up 4 to 10% grades, climbing adds 199 to 283 Wh per 1,000 feet on the throttle; the range tables break it down.

How fast does the Freesky Swift Horse Ultra go?

As delivered, 20 mph: Freesky's FAQ says its bikes are limited to 20 mph by default. Freesky's page publishes 38 mph on the throttle and pedal assist, and its FAQ says going past 20 mph requires "a license, license plates, and insurance".

Is the Freesky Swift Horse Ultra street legal, and what class is it?

By default its help stops at 20 mph, the line where California's class 2 throttle must stop; each definition also sets a 750 W line and Freesky lists peak output, so ask us for the continuous rating in writing. At the published 38 mph it is past every class's speed line, where Freesky's FAQ asks for a license, plates and insurance.

What motor does the Freesky Swift Horse Ultra X-6E have?

A Bafang rear hub motor that Freesky lists as a "4000W Peak BAFANG Brushless Motor" with 150 N·m of torque, driving the rear wheel, with a cadence sensor and a thumb throttle to call on it. The motor section covers what a peak rating means.

How long does it take to charge the Swift Horse battery?

Freesky's comparison chart gives 8–10 hours for the Swift Horse Ultra, on the US-standard 3 A charger in the box. The manual asks you to charge in a dry place at 50 to 77 °F and only between 32 and 104 °F.

Can you replace the Swift Horse Ultra's battery?

Yes: the pack's lock opens with its key and the pack comes off the bike, under the "Remove the battery" steps in the manual, and Freesky's store lists an "Extra Battery Pack" among its accessories. Freesky's battery guide puts most lithium-ion e-bike batteries at "three to five years or approximately 500 to 1,000 charge cycles", as general guidance; email us before you buy a spare and we will confirm the fit with Freesky.

What reduces the Freesky Swift Horse's real-world range?

Speed first: at 20 mph a full charge computes to 68 miles against 96 at 15, on the throttle. Climbing costs 199 to 283 Wh per 1,000 feet, a 300 lb load takes the 15 mph ride to 79 miles, freezing air to about 117 miles on the easy-pedaling ride that covers 158 at 77 °F, and the highest-drag tire of the ten to 88 (the range section).

What is the real-world battery life in cold weather?

At 32 °F the pack gives back about 89% of its 77 °F energy, 80 to 93% across published cell data, so the easy-pedaling 15 mph ride falls from 158 miles to about 117. The manual rules out riding, storing and charging below 32 °F (the cold table).

How much does the Freesky Swift Horse Ultra weigh?

83 lb, as both Freesky's specification and its comparison chart list it. Plan racks and lifts for that weight plus whatever you carry on the bike (the weight section).

What rider heights fit the Freesky Swift Horse Ultra?

Freesky publishes 5'3" to 6'8" and an inseam of 27 to 35 inches. For the US Army's survey bodies, the saddle reaches 109% of inseam for 84 of 100 riders at 5'6" and 53 of 100 at 5'8": a 5'8" rider with the median 32.6-inch inseam needs 40.4 inches from the ground to the saddle, against the 40.5-inch top of the post (the fit section).

Is the Freesky Swift Horse Ultra UL certified?

Yes. Freesky links a UL 2849 certificate naming model X-6E, dated May 9, 2025, and a UL 2271 certificate for the 35 Ah pack, dated March 17, 2025, both from TÜV SÜD America (the UL section).

Is the Freesky Swift Horse Ultra worth buying?

At $1,599 on our store on September 25, 2026, with $2,449 shown as the regular price and free shipping within the contiguous United States, it puts a 4,000 W peak Bafang motor, 1,680 Wh, full suspension and four-piston hydraulic brakes on one frame. It suits riders 18 and over from 5'3" up who want long rides on rough ground, with the saddle at its top past a 32.7-inch inseam (the verdict).

Can I finance the Freesky Swift Horse Ultra?

Yes: Shop Pay on our listing showed a sample plan on September 25, 2026 of $144.32 a month for 12 months at 15% APR, $1,731.84 in total, subject to an eligibility check by Affirm's lending partners. You see the plan you are offered before you pay.

What warranty does the Swift Horse Ultra have?

Bought from us, a fault comes to us: with photos or video and your order number, our listing says we "file and manage the claim with Freesky on your behalf" (buying it from us). Before you order, email us and we will have Freesky confirm the warranty terms for your order in writing.

Where do I find the Freesky Swift Horse manual?

Freesky's product page links it under "Download User Manual": the X-6E PDF quoted throughout this review, covering assembly, start-up, the display, tire pressure, temperatures and the warranty.

How hard is the Swift Horse to assemble?

It arrives partly built: the manual's box list puts the front wheel, the saddle and the pedals in the carton beside the bike, with two wrenches and seven Allen keys, and Freesky's page links an unboxing video. Before the first ride, the manual asks that "a certified, reputable mechanic has inspected the assembly."

Is Freesky legit?

Look at the record for this bike: no CPSC recall record names the brand as of September 25, 2026, Freesky publishes a UL 2849 certificate for the X-6E, and its manual names the maker, Yansan Technology, on the cover. The verdict says who the Swift Horse Ultra suits.

Limitations of this review

Twenty things this review cannot settle, listed so you can weigh them.

1. We sell this bike. Read the red flags with the same attention as the green.
2. This is a specification-verified review. Its figures come from Freesky's published documents, statutes, our own store record, the published research the range and fit sections cite, or arithmetic on this page.
3. Each range figure is for a steady ride: one speed on one grade with no wind and no stops. Stops, starts and headwinds cost more, and a tailwind less.
4. Bafang's figures stand in for Freesky's motor. Freesky gives peak output, 4,000 W, and 150 N·m; the model uses Bafang's published figures for a 1,000 W 48 V geared hub, reading its n0 and nT as the no-load and rated speeds, 41.9 and 35.0 mph on the 27.6-inch wheel. Freesky's documents read here do not say whether the hub is geared or direct drive. At 82% efficiency in place of Bafang's 80% floor the 15 mph throttle figure moves from 96 miles to 102; on Bafang's 750 W version it is 93.
5. No ride of this model to an empty battery checks the model. A YouTube search under four phrasings found an assembly video, short specification summaries and one UK review, and none carries a ride to empty with the rider's weight and speed stated; the 144 owner reviews on Freesky's page give battery-bar readings on partial rides. The physics reproduces Martin and colleagues' worked example and the motor reproduces Bafang's 80% at the rated point; no measured hub-motor map was available to check the motor model at light loads.
6. Every figure assumes Freesky's 1,680 Wh. At the 47.19 V the pack's certificate prints, 35 Ah is 1,651.7 Wh, which would shorten each full-charge figure by about 1.7%. The documents read here do not say how much of the pack the battery management releases; on one measured pedelec, researchers at KIT found 75% used in a standard range test.
7. The tire coefficient is the median of ten 26 × 4.00 fat tires at 12 psi, a stand-in for the CST BFT on the bike, and the tire table brackets it with the lowest and highest of the ten.
8. The cold figures rest on one cell's laboratory data. Freesky's page names LG cells without a model, so the central line uses McMaster University's measured LG HG2 cell, bracketed by other published cell data, with the cells assumed to be at air temperature.
9. Where Freesky's documents differ, this review follows the product page read on September 25, 2026, which gives "4000W Peak", 150 N·m and "LG Cells". Freesky's August 14, 2026 torque explainer lists "3500W Peak BAFANG" and 140 N·m for this model; its May 18, 2026 tire guide a "Peak 3500W BAFANG motor" and a "48V 35Ah Samsung battery"; its May 11, 2026 range post a "48V 35Ah Samsung battery"; and its June 12, 2026 charging guide "48V 35Ah Samsung / LG cells". On request we will get any of these confirmed by Freesky in writing.
10. The throttle row differs between documents. The page specifies a thumb throttle, while the manual Freesky links, which carries an earlier build's name on its cover, describes "rotating the throttle backward toward the rider". No range figure depends on it.
11. Freesky prints two standover heights. Its Size & Fit table gives 21 inches and its Geometry table on the same page 28; the standover line on its drawing measures 30.0 at the wheelbase scale. The fit model computes at 21 and the standover table prints the clearance at all three.
12. The owner reviews span builds. Freesky's page carries 144 reviews; of the 40 it displays with a build name, 13 name this Ultra build, the earliest dated June 12, 2026. The owners quoted here wrote about this build, and the reviews that give a rider's height, all written before June 12, 2026, are not used for fit.
13. Trail access is set locally. Your land manager's rule decides, it can change, and neighboring systems differ; this page does not replace it.
14. The recall search covers the CPSC's US database under the names listed; a recall filed under another company name would need that name searched.
15. Stock and price were read on September 25, 2026, and both can change.
16. The range model uses the 27.6-inch wheel Freesky lists. On Freesky's drawing, scaled by its wheelbase, the tires measure 29.0 inches across (the drawing's wheel-diameter line runs on past them, to 31.1); on the measured wheel the level 15 mph throttle figure is 95 miles in place of 96 and the 8% climb 13 in place of 14.
17. The fit figures use the US Army's ANSUR II bodies: 6,068 soldiers aged 17 to 58, measured in 2010 to 2012, who are not the US public, so your own inseam decides your row.
18. The cockpit is the one in Freesky's drawing. The crank-axle height, the seatpost and the grips are measured on it, and the point where your sit bones rest on the saddle is bracketed from the saddle's shape; where the drawing and the Size & Fit table disagree, the model keeps the table's seat range.
19. The hand figure is a ceiling with a relaxed back. On a real ride your back and arms carry part of it, and we found no study that measures the hand load on a bike set up like this one.
20. The 109% formula is a starting point. In 19 trained cyclists it put 55 to 65% inside the 25-to-35-degree knee range and the heel check put 70%, so the knee range and the heel check set the saddle.

The bottom line

For $1,599, the Swift Horse Ultra puts a 4,000 W peak Bafang rear hub motor and a removable 1,680 Wh pack on a full-suspension fat-tire frame, with four-piston hydraulic brakes, lights and turn signals, a rack and mudguards.

On level pavement a 180 lb rider gets about 96 miles at 15 mph on the throttle and 158 with easy pedaling, and each 1,000 feet of climbing takes 199 to 283 Wh at 10 mph on the throttle.

It suits long rides on dirt roads, gravel and rough pavement for riders 18 and over from 5'3" up who can store and lift an 83 lb bike; past a 32.7-inch inseam the saddle rides at its top. With Shop Pay on our listing that is $144.32 a month for 12 months at 15% APR, $1,731.84 in total, subject to an eligibility check.

Before you pay, settle the class: the bike is limited to 20 mph by default, Freesky publishes 38, and on Freesky's own account anything faster needs a license, plates and insurance. Tell us where you will ride before you order, and we will get Freesky's continuous motor rating in writing if a watt line applies.

Source register

Each document this review relies on, and what it supports.

T1 is the record itself, read from the party that issued it: a statute, a federal regulation or notice, a certificate, the maker's own product page, record and manual, our own store record.

T2 is a party's own publication about its product or its measurements: the maker's guides and posts, the motor maker's workbook, the research groups' and laboratories' published measurements.

Expiry conditions

Re-read this page if Freesky changes the Swift Horse Ultra's price, specification, range band, 20 mph default, Size & Fit or Geometry table, or geometry drawing on its product page; if Freesky answers our written questions on the continuous motor rating or the standover height; or if the stock, the price or the Shop Pay terms change on our store.

Re-read it as well if a recall is published naming Freesky or Yansan Technology. Verified September 25, 2026.

References

The full bibliographic record for each document cited above, with the date it was retrieved.

1. FREESKY, Swift Horse Ultra X-6E — product page (Technical Specification, Size & Fit, Geometry, More Features, comparison chart, FAQ, customer reviews, as rendered). Retrieved September 25, 2026. https://www.freeskycycle.com/products/swift-horse-ultra-x-6e
2. FREESKY, Swift Horse Ultra X-6E — product record, body_html feature list, variant prices, compare-at prices, SKUs and creation date. Retrieved September 25, 2026. https://www.freeskycycle.com/products/swift-horse-ultra-x-6e.json
3. FREESKY / YANSAN Technology Co., Ltd., X-6E electric bike user manual: Before your first ride, What's in the Box, How to Turn on the Battery, Tire Inflation, safety instructions, Bike Performance Disclaimer, Warranty. Retrieved September 25, 2026. https://cdn.shopify.com/s/files/1/0605/5188/9131/files/X-6E_Instruction_English.pdf
4. TÜV SÜD America, Inc., Certificate No. U14 128702 0006 Rev. 00, UL 2849:2020/R:2022-12, Electrical Systems for E-Bikes, brand FREESKY, model X-6E, dated May 9, 2025. Retrieved September 25, 2026. https://cdn.shopify.com/s/files/1/0605/5188/9131/files/UL2849-Swift-Horse-X-6E.pdf
5. TÜV SÜD America, Inc., Certificate No. U10 128702 0001 Rev. 00, UL 2271:2018, Batteries (Rechargeable Li-ion Battery), model FP4835R0, 47.19 V, 35 Ah, dated March 17, 2025. Retrieved September 25, 2026. https://cdn.shopify.com/s/files/1/0605/5188/9131/files/UL2271-Swift-Horse-Ultra-X6E-35Ah.pdf
6. California Legislative Information, California Vehicle Code § 312.5, subdivisions (a), (a)(2) and (a)(3). Retrieved September 25, 2026. https://leginfo.legislature.ca.gov/faces/codes_displaySection.xhtml?lawCode=VEH&sectionNum=312.5.
7. US Government Publishing Office, 15 U.S.C. § 2085 — Low-speed electric bicycles, subsection (b). Retrieved September 25, 2026. https://www.govinfo.gov/content/pkg/USCODE-2024-title15/html/USCODE-2024-title15-chap47-sec2085.htm
8. Bureau of Land Management, 43 CFR § 8340.0-5, paragraphs (a)(5) and (j) (85 FR 69223, Nov. 2, 2020). Retrieved September 25, 2026. https://www.ecfr.gov/current/title-43/subtitle-B/chapter-II/subchapter-H/part-8340
9. Forest Service, US Department of Agriculture, 36 CFR § 261.13 — Motor vehicle use. Retrieved September 25, 2026. https://www.ecfr.gov/current/title-36/chapter-II/subchapter-B/part-261/subpart-A/section-261.13
10. Forest Service, US Department of Agriculture, 36 CFR § 261.1b — Penalty (89 FR 92815, Nov. 25, 2024). Retrieved September 22, 2026. https://www.ecfr.gov/current/title-36/chapter-II/subchapter-B/part-261/subpart-A/section-261.1b
11. US Forest Service, Directive Publication Notice, 87 FR 41278 (July 12, 2022), recording the final e-bike directives issued March 31, 2022. Retrieved September 24, 2026. https://www.federalregister.gov/documents/2022/07/12/2022-14777/directive-publication-notice
12. US Consumer Product Safety Commission, Recall database, full-field search across a 623-record corpus, controls Ancheer / Specialized / Trek, direct title, description, product-name and manufacturer queries for Freesky, and a name screen for Yansan, the X-6E and the Swift Horse. Retrieved September 25, 2026. https://www.saferproducts.gov/
13. Redtail eBikes, Shipping policy. Retrieved September 25, 2026. https://redtailebikes.com/policies/shipping-policy
14. Redtail eBikes, Refund policy (48-hour damage window, manufacturer-warranty coordination, change-of-mind and cancellation terms). Retrieved September 25, 2026. https://redtailebikes.com/policies/refund-policy
15. Redtail eBikes, Freesky Swift Horse Ultra X-6E storefront record and Shop Pay terms (price, compare-at price, availability by colorway, sample plans). Retrieved September 25, 2026. https://redtailebikes.com/products/freesky-swift-horse-ultra-x-6e
16. Affirm, Affirm's lending partners (the lenders behind Shop Pay Installments, as our listing names them). Retrieved September 25, 2026. https://www.affirm.com/lenders
17. FREESKY, Best Hunting E-Bikes: Which FREESKY Electric Bike Is Right for Your Outdoor Adventure? (September 8, 2026), the payload paragraph and the Swift Horse Ultra X-6E section. Retrieved September 25, 2026. https://www.freeskycycle.com/blogs/news/best-hunting-e-bikes-which-freesky-electric-bike-is-right-for-your-outdoor-adventure
18. FREESKY, Summer High-Temperature Charging Guide: How to Charge Your eBike Safely in Hot Weather (June 12, 2026). Retrieved September 25, 2026. https://www.freeskycycle.com/blogs/news/summer-high-temperature-charging-guide-how-to-charge-your-ebike-safely-in-hot-weather
19. FREESKY, 7 Signs Your E-Bike Battery Needs Replacement: Lifespan, Warning Signs and Solutions (March 6, 2026). Retrieved September 25, 2026. https://www.freeskycycle.com/blogs/news/7-signs-your-e-bike-battery-needs-replacement-lifespan-warning-signs-and-solutions
20. FREESKY, E-Bike Torque Explained: What It Means and How Much Torque Do You Actually Need? (August 14, 2026). Retrieved September 25, 2026. https://www.freeskycycle.com/blogs/news/e-bike-torque-explained-how-much-torque-do-you-need
21. FREESKY, How Tire Width Affects the Riding Experience: A Guide to Fat Tire E-Bikes (May 18, 2026). Retrieved September 25, 2026. https://www.freeskycycle.com/blogs/news/how-tire-width-affects-the-riding-experience-a-guide-to-fat-tire-e-bikes
22. FREESKY, How Far Can an Electric Bike Go? Tips for Planning Longer Summer Rides (May 11, 2026). Retrieved September 25, 2026. https://www.freeskycycle.com/blogs/news/how-far-can-an-electric-bike-go-tips-for-planning-longer-summer-rides
23. BAFANG, Workbook OEM 2021, MOTORS table, RM G0H0 column: n0, nT, rated power, efficiency, maximum torque at 48 V. Retrieved September 23, 2026. https://www.bafang-e.com/Uploaded/Labels/BAFANG%20Workbook%20OEM%202021.pdf
24. Martin, J. C., Milliken, D. L., Cobb, J. E., McFadden, K. L. and Coggan, A. R., Validation of a Mathematical Model for Road Cycling Power, Journal of Applied Biomechanics 14(3):276–291 (1998), Eq. 14 and Appendix I; doi 10.1123/jab.14.3.276. Retrieved September 23, 2026. https://collections.lib.utah.edu/dl_files/b4/8e/b48ef26086091662c561e673d7bd990d77868437.pdf
25. Bierman, J., Fat Bike Tires Test Results, BicycleRollingResistance.com, rolling resistance at 12 psi, 28.8 km/h, 42.5 kg. Retrieved September 25, 2026. https://www.bicyclerollingresistance.com/fat-bike-reviews
26. Bierman, J., Kenda Juggernaut Pro 2016, BicycleRollingResistance.com, rolling-resistance results. Retrieved September 25, 2026. https://www.bicyclerollingresistance.com/fat-bike-reviews/kenda-juggernaut-pro-2016
27. Bierman, J., CRR at Different Temperatures: Examining Temperature Dependence of Rolling Resistance, BicycleRollingResistance.com. Retrieved September 23, 2026. https://www.bicyclerollingresistance.com/specials/crr-temperature-test
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