Comparison · Fitness · 2 models
Sunny Smart Folding X-Bike vs Yosuda EB4: two folding bikes with bands, on levels, rider weight and floor space
Two folding X-frame bikes that add resistance bands for the arms. Sunny's has 14 magnetic levels, a mesh backrest, Bluetooth to its own app and transport wheels, with the maker's page behind most of it. Yosuda's lists 16 levels, a 172 kg rider limit and the smallest footprint in use, with most of its figures on the listing only. The decision is room, rider and how much a checkable figure matters.
Quick answer
Side by side
| Model | Resistance | Max user weight | Positions | App | Folds | Footprint in use | Weight | Flywheel | Where to buy |
|---|---|---|---|---|---|---|---|---|---|
| Sunny Health & Fitness Smart Folding X-Bikethe bike with a backrest, an app and a maker's page | 14 levels, magnetic | 135 kg | Upright and semi-recumbent with backrest; arm bands | Bluetooth, SunnyFit | Yes, with transport wheels | 97 × 56 × 134 cm | 23.5 kg | No confirmed data | View listing |
| Yosuda EB4 5-in-1 Folding Bikethe bike with the highest rider limit and smallest footprint | 16 levels, magnetic† | 172 kg† | Upright, recumbent, arm bands (5-in-1) | No confirmed data | Yes, about 70% less floor space | 66 × 45 × 122 cm† | No confirmed data | 3 kg† | View listing |
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† Figure from a retailer listing or otherwise awaiting confirmation from the manufacturer; other figures come from manufacturer manuals and leaflets.
Sunny’s levels, positions, app and folding are from its product page; its rider limit, footprint and weight are from the UK listing. Yosuda’s page gives the folding saving and a level range by version; its levels, rider limit, flywheel and footprint are from the listing and flagged. Yosuda publishes no bike weight.
Levels and feel
the bike with a backrest, an app and a maker's page
Sunny Health & Fitness Smart Folding X-Bike
- Resistance
- 14 levels, magnetic
- Max user weight
- 135 kg
- Positions
- Upright and semi-recumbent with backrest; arm bands
- App
- Bluetooth, SunnyFit
- Folds
- Yes, with transport wheels
- Footprint in use
- 97 × 56 × 134 cm
Check price
Fourteen levels of magnetic resistance with resistance bands built into the frame, an adjustable padded seat with a mesh backrest, Bluetooth to the SunnyFit app, and a frame that folds onto transport wheels. Maximum rider 135 kg, 97 by 56 by 134 centimetres in use and 23.5 kg, by the UK listing.
Strengths
- A maker's page and a UK presence behind it
- Backrest and bands for a seated session
- 14 levels, Bluetooth app
Limitations
- 23.5 kg is a lot to fold and wheel away
- Maximum user weight quoted differently in the UK and US
Good for
- a flat with somewhere to wheel it, and a rider who wants back support
Look elsewhere if
- anyone who needs to lift it into a cupboard
the bike with the highest rider limit and smallest footprint
Yosuda EB4 5-in-1 Folding Bike
- Resistance
- 16 levels, magnetic†
- Max user weight
- 172 kg†
- Positions
- Upright, recumbent, arm bands (5-in-1)
- Folds
- Yes, about 70% less floor space
- Footprint in use
- 66 × 45 × 122 cm†
- Flywheel
- 3 kg†
Check price
Sixteen magnetic levels and a 3 kg flywheel by the listing, which Yosuda’s own page qualifies as 8 to 16 levels depending on version. Five positions with bands, a 172 kg limit and 66 by 45 by 122 centimetres in use, all by the listing; Yosuda states the folded frame saves about 70% of floor space.
Fourteen checkable levels against sixteen claimed ones; more steps is finer adjustment, not more effort at the top.
Strengths
- 172 kg limit, by the listing
- Smallest footprint in use here
- Five positions including bands
Limitations
- The 3 kg flywheel is light; expect a less smooth pedal than the heavier bikes
- Weight not published
Good for
- a heavier rider in a small room
Look elsewhere if
- anyone chasing a road-bike feel
The seat
The Sunny’s mesh backrest makes a semi-recumbent position possible: you lean back, the bands are within reach, and longer sessions are kinder to the lower back. The Yosuda lists upright and recumbent positions among its five; its listing gives fewer details of the seat.
Floor space
Sixty-six by 45 centimetres for the Yosuda in use, against 97 by 56 for the Sunny, both by the listings. That is about a third shorter and a fifth narrower for the Yosuda, which matters in a bedroom corner. Folded, Yosuda says about 70% less floor; Sunny gives no percentage but adds wheels.
Rider weight
172 kg on the Yosuda listing; 135 kg on the Sunny’s UK listing, with Sunny’s US pages giving a different figure in pounds. For a heavier rider the Yosuda’s figure is the higher, and it is still worth confirming with the seller before buying.
The app
SunnyFit by Bluetooth on the Sunny, optional; the bike works without it. No app is listed for the Yosuda. For someone who rides more when a phone is keeping track, that counts.
Which one, by rider and room
- Wants back support for longer sessions: Sunny X-Bike.
- Heavier rider: Yosuda EB4, by its listing.
- Smallest corner of a room: Yosuda EB4.
- Wants to roll it away after each ride: Sunny X-Bike.
- Wants figures from the maker: Sunny X-Bike.
Sources
Facts checked 10 November 2026
- Sunny Health & Fitness — Full Body Foldable Magnetic X-Bike Pro SF-B223012 product page — Manufacturer documentation, checked 23 October 2026
- Retail listing (Sunny Health & Fitness) — Retailer listing, checked 23 October 2026
- Retail listing (YOSUDA) — Retailer listing, checked 23 October 2026
- Yosuda — folding exercise bike (EB4) product page — Manufacturer documentation, checked 23 October 2026
Which takes a heavier rider?
The Yosuda, by its listing: 172 kg, against 135 kg for the Sunny on its UK listing. Yosuda's own page does not state a limit, and Sunny's US pages quote a different figure in pounds, so both numbers carry a flag. Either way, the Yosuda's stated limit is the higher.
How many resistance levels does each really have?
Sunny's page states 14 magnetic levels. The Yosuda listing says 16; Yosuda's own page says 8 to 16 depending on the version, so check the version you are buying. More levels mean finer steps, not a harder top end.
Which is easier to move?
The Sunny has transport wheels and its listing gives 23.5 kg. Yosuda does not publish a weight. Both fold; Yosuda says its frame saves about 70% of floor space folded. If the bike lives behind a door between sessions, the wheels count.
Do they need an app?
No. The Sunny connects by Bluetooth to Sunny's SunnyFit app, and works without it. The Yosuda has no app listed.
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