Dyu D3F - 250W - Folding E-Bike | Sähköpyörätehdas

🚴 Dyu D3F Folding E-Bike – Small but Mighty

When the Dyu D3F folding e-bike arrived at the joint test facility for European e-bike manufacturers in Kruunuvuorenranta, Helsinki, many on the team thought at first glance that it was a toy. But when the first test rider turned the handlebar, the bike took off like a cheetah in an urban jungle—silently, lightly, and with incredible stability.

A moment later, someone shouted:
“This isn’t an electric bike—it’s a ninja!”

From the very first few meters, the Dyu D3F folding e-bike proved that size isn’t everything. It glides effortlessly through city streets, fits in an elevator, gets on a train, and takes you 60 kilometers away without breaking a sweat. It’s not just a bike—it’s an improvement in quality of life packed into a compact frame.

⚙️ Dyu D3F Folding E-Bike – Technical Specifications

Motor: 250 W brushless rear-mounted motor
Battery: 36 V, 10 Ah removable lithium battery
Range: up to 60 km on a single charge
Top speed: 25 km/h
Tires: 14 inches, compact yet stable
Design: Foldable frame – easy to transport or store
Brakes: Disc brakes front and rear
Weight: about 17–19 kg
Weight capacity: max 120 kg
Cruise mode: automatic speed maintenance after 8 seconds
Charging time: about 5–6 hours
IP rating: IP54 – splash-proof

🛠️ Comments from the Kruunuvuori test team

“It goes where larger bikes can’t fit—it’s like a foldable Tesla bike.”
“Surprisingly sturdy and quiet to ride, especially in the city.”
“When folded, it looks like a bag, but when unfolded, it’s a full-fledged ride.”
“Perfect for students, commuters, or city dwellers.”

🎥 We saw it in action

The test ride clearly showed that the Dyu D3F folding e-bike doesn’t lag behind—it rides smoothly on both city streets and sandy roads. The test group unanimously concluded that this bike’s deceptively compact exterior hides the soul of a true e-bike.

🧠 Why choose the Dyu D3F folding e-bike?

Since you need a vehicle that:

Folds down to a compact size but offers a wide operating range
It's lightweight, yet sturdy
It operates discreetly but effectively
It doesn't take up much space, but it takes you a long way

The Dyu D3F folding e-bike is the "pocket rocket" of e-bikes. It's the perfect choice for anyone who wants efficient transportation without compromising on size or style.

We also want to share useful information about the world of e-bikes. If you’d like to learn more about e-bikes, their benefits, and how they can be used, I recommend checking out the following resources:

Network of Cycling Communities– Up-to-date information on cycling in Finland.
Traffic Safety– Tips for Safe Electric Biking.
Fillari Magazine– Articles and reviews on cycling and e-bikes.
Motiva– Information on sustainable transportation solutions.

I hope you find some useful information in these links!

Best regards,
The SähköpyöräTehdas Team

Motor: 250 W brushless rear-mounted motor
Battery: 36 V, 10 Ah removable lithium battery
Range: up to 60 km on a single charge
Top speed: 25 km/h
Tires: 14 inches, compact yet stable
Design: Foldable frame – easy to transport or store
Brakes: Disc brakes front and rear
Weight: about 17–19 kg
Weight capacity: max 120 kg
Cruise mode: automatic speed maintenance after 8 seconds
Charging time: about 5–6 hours
IP rating: IP54 – splash-proof

Electric Bike Factory Warranty – We're Here to Support You

All electric bicycles come with a manufacturer's warranty that covers the most important parts as follows:

Frame: 10-year warranty against manufacturing defects.
Electric motor and its components: 2 years.
Battery: 2 years.
Other electrical components: 2 years.

The expert staff at Sähköpyörätehdas will support you throughout the entire warranty process, so you
don't have to worry. We'll handle everything for you directly with the manufacturer.

How we handle warranty issues on your behalf:

1. If a problem arises – Contact us at
If your electric bike develops a fault, contact Sähköpyörätehdas customer service immediately. You can
contact us by email, phone, or by filling out the warranty form on our website.
We ask that you describe the problem in detail and send any photos or
videos of the issue, along with your purchase information. This will allow us to assess the problem as quickly as possible.

2. Problem Assessment and Inspection
When you contact us, our expert will assess the situation and determine whether the problem is covered by the warranty
. If necessary, we’ll direct you to the nearest service center or arrange for your bike to be picked up
for a more detailed assessment. We’ll take care of everything for you—all you need to do is report
the problem and send your bike in for inspection.

3. Warranty Processing – We’ll handle communication with the manufacturer
Once we’ve confirmed that the defect is covered by the warranty, the Sähköpyörätehdas staff will handle
all communication with the manufacturer on your behalf. This includes submitting the necessary documents and information
as well as ordering any replacement parts. A warranty repair may involve replacing a part,
repairing the bike, or even delivering a new bike if the defect cannot be repaired.

4. Fast and Efficient Service
We ensure that the problem is fixed as quickly and professionally as possible. We’ll handle
all service-related arrangements for you, so you don’t have to worry about the details.
We’ll keep you updated throughout the process and notify you as soon as the service or repair is complete.

5. After a warranty repair – We’ll arrange for the return at
Once the problem has been fixed or the defective part has been replaced, we’ll notify you and arrange for the return or pickup of your bike at
We’ll make sure everything is in order before we return the bike to you at
.

6. Costs Covered by the Warranty
If the defect is covered by the warranty, repairs, part replacements, and return shipping are completely free of charge for you.
If the defect is not covered by the warranty, we will offer you a paid repair service and provide
a cost estimate before starting the work.

Sähköpyörätehdas Supporting You Every Step of the Way

We are committed to ensuring that your electric bike works flawlessly throughout the warranty period.

We'll handle all warranty matters with the manufacturer on your behalf, so you can focus on carefree
driving.

Sähköpyörätehdas's customer service is always ready to help you—just contact us at
and we'll take care of everything for you.

Maintenance and Assembly of Electric Bikes at the Electric Bike Factory

You can have your electric bike serviced either at our store in Helsinki or at service centers located elsewhere in Finland. You can easily find your nearest service location [here].

Assembling an Electric Bike

When you buy an e-bike from us, you can rest assured that we’ve made everything as easy as possible for you. Our e-bikes come 90% pre-assembled, which means you don’t have to worry about complicated assembly steps. For the final assembly, you’ll receive all the necessary tools and clear, step-by-step instructions to ensure your e-bike is ready to ride in just about 30 minutes.

However, if you need help at any stage, we’re here to assist you. You can contact us at any time, and we offer free video guidance via WhatsApp to ensure the assembly goes smoothly. If you’d still rather not assemble the e-bike yourself, you can also bring it to our store, and we’ll assemble it for you—this service is also designed to keep the process easy and hassle-free.

First Aid

The first service should be performed after about one month of riding or when the e-bike has been ridden 100–300 kilometers. This initial service includes a thorough wash of the e-bike, a comprehensive inspection of the electrical components, adjustments to the brakes and gears, tightening of the spokes, lubrication of the chains, and a general condition check. This service ensures that your e-bike is in top condition and ready for safe riding.

Annual Maintenance

Annual maintenance includes even more comprehensive procedures: battery testing, drivetrain cleaning, tire inflation and replacement, chain lubrication, and inspections and updates of all electrical systems. We recommend annual maintenance regardless of how often you use your e-bike, to ensure it remains in top technical condition and safe to ride all year round.

Prices for Maintenance and Repair Services

We keep our maintenance costs competitive. The price for an initial service starts at 90 EUR, and a comprehensive annual service costs 149 EUR (including 25.5% VAT).

If you'd like us to assemble your electric bike for you, you can bring it to our store; the assembly service costs 69 EUR.

Service and Assembly Appointment

You can schedule a service appointment or a pickup by calling our store directly or visiting our website.

If you can't make it to our store in Helsinki, you can take advantage of our service network, which covers all of Finland. [Click here] to see all of our service locations and their contact information.