The DYU D3F is most likely the least expensive folding e-bike available. We conducted tests to see if the model would work for commuters and other users.
The DYU D3F is one of the e-folding bikes that we have tested that is incredibly small when unfolded. It is barely longer than an office chair and has tiny 14-inch wheels. But everything is there: electric motor, folding mechanism, lighting, disc brakes, and a saddle with a spring-loaded seat.
The D3F is thus a viable option for a quick commute between the S-Bahn and the workplace. When folded up, cyclists don’t even need to purchase an additional ticket, saving both time and money for the device. Amazon, which charges a reasonable $429, is also significantly less expensive than the costs of rival candidates. When compared: The Fiido D2S, which is similarly outfitted, costs a good $539, which is nearly $100 more. Will you, however, be content with the DYU mini folding bike?
The test’s DYU D3F is intended for commuters from the lowlands. In our articles on the Fiido M1 and Mate X, you can find potential alternatives if you prefer a folding bike for mountains, meadows, and other terrain.
| Frame material | Metal |
| Rated power | 250 W |
| Max speed | 15.5 Mph |
| Uphill | 15° |
| Pedal Height | 120 mm |
| Battery | 10 Ah |
| Range in throttle mode | 20-30 Mi |
| Range in pedal assist mode | 30-37 Mi |
| Waterproof level | IP54 |
| Folded | 1170 x 200 x 720 mm |
| Full | 1170 x 500 x 990 mm |
| Weight | 38 lb |
DYU D3F: Design and Build Quality
The DYU D3F appears to be the creation of a designer of circus equipment at first glance. The middle of the bike’s teardrop-shaped battery housing, which has a knobbly appearance, grabs everyone’s attention. In comparison to many other e-folding bikes, the D3F’s form factor, which takes some getting used to, has a significant advantage in that it can be easily lifted with one hand and balanced in a trunk or S-Bahn car. This is crucial for this model because everything else relies on the handlebars and pedals to function.
Other bicycles, including the high-end folding Brompton Electric and the Fiido D2S, can be folded up to a size of 58 x 62 x 33 or 75 x 65 x 45 centimeters. The DYU D3F’s dimensions of 112 x 65 x 30 cm ensure its constant heft. The handlebars are perfectly parallel to the frame when folded.
The least expensive configuration of our test device. The entire range is equipped with generic disc brakes, a bell, an on/off switch, a button for the integrated front light, a separate clip-on rear light, a charge level indicator, a 250 watt-hour battery, and a side stand. You must shell out well over $100 for a display that includes a speedometer and an always-on rear light. There are no different battery types.
Unquestionably, the D3F is well made. The brakes have good stopping power, the saddle is snug, and the frame is stable. The bike has an odd design, but it seems to be well made. Up to 120 kilograms of weight can fit on the saddle.
Details are where criticism lies. The plastic safety lock on the handlebar folding mechanism is of low quality. Even though the lock is secure, we would still prefer a higher standard safety device because, in the end, it might be the driver’s health that depends on it. The controls, such as the light-switching buttons, also don’t seem to be long-lasting. The mechanics are extremely shaky, and the plastic used feels cheap. Aside from that, the DYU D3F lacks a gear shift, which is another very annoying situation. So, even if your battery is dead, you can still move forward by pedaling vigorously on the 14-inch tires without under- or gearing.
For many interested parties, the height-adjustable saddle will be a stipulation for exclusion. People over 1.70 meters tall will have to accept a significant loss in comfort when pedaling because the seat post can only be extended by a maximum of 86 centimeters using a quick-release fastener. The D3F weighs 17 kilograms, which puts it between the 14.5 kilogram Brompton Electric and the 20 kilogram Fiido D2S.
The bike’s throttle is the primary area of criticism. Despite being extremely comfortable due to the bike’s small size and lack of gears, it is not permitted in Germany. It’s unfortunate because the saddle on the e-bike transforms it into a comfortable alternative to e-scooters. Other European nations are not subject to this prohibition.
DYU D3F: Motor and BatteryÂ
The D3F has a small, child-like ride. When pedaling, anyone taller than 1.70 meters will have their knees at hip height. Additionally, the support for the electric motor is poorly designed. The engine starts when you reach the required speed of 6 km/h. However, the thrust is so great that you actually pedal while the engine is idling. Simply put, there is no gear shift or finer tuning in this.
The specified 25 km/h is quickly attained with the throttle, at least on flat terrain. The motor support deteriorates and collapses as soon as there is even a slight increase of a few percent. Anyone picturing, for instance, the incline of a wheelchair access also considers the motor’s capacity. The only thing that works in this situation is vigorously dismounting or trampling.
However, the D3F performs admirably when driving on flat terrain. It is enjoyable even on gravel paths, offers a stable ride, and swings easily around corners. The spring-loaded saddle typically makes up for the absence of frame suspension.
The internal battery can produce 250 watt hours. For comparison, the Fiido D2S offers 270 watt hours. It is noticeably more agile. The D3F has a range of 20 to 40 kilometers under ideal circumstances, according to the manufacturer. In practice with pure pedal support we are at almost 30 kilometers. You can travel about 15 kilometers if you only use the throttle.
E-bikes typically offer various pedal assistance modes to increase range. The DYU folding bike is completely devoid of these. The maxim “all or nothing” directs you to pedal as hard as you can until the battery runs out. For charging, a 1.5 amp power supply unit is utilized. In about 4 hours, the battery is fully recharged.
DYU D3F: Conclusions
On campsites and other locations in other European nations, the DYU D3F makes a good travel companion. It is sufficiently well made and incredibly affordable, making it the perfect e-scooter substitute for city use, camping, etc.
The design would be perfect for short commuter routes on flat terrain. However, the only legal way to ride a bike in this nation is against the law. Despite all the criticisms, the D3F would actually make a great alternative to e-scooters, which is a shame.
The DYU D3F regularly costs $429 with shipping from an US warehouse in the cheapest equipment configuration. Potential suppliers include Banggood, Geekbuying, and Gearbest. We received the test device from bi, who also provided a discount code.Â
