DYU A5 Review: Six Weeks with the Only Folder with a Remote Lock
The DYU A5 is the only folder in DYU's lineup with a remote lock. Six weeks ago I would have called that a marketing gimmick. Now, after parking the bike outside my Viennese school every day, I'd call it the feature that justifies the purchase.
I teach at a Gymnasium in the Vienna 7th district. The bike rack outside my school is covered but not fenced, in full view of the Mariahilfer Straße, and has a reputation problem — at least four colleagues have had bikes stolen from it in the past three years. For me the A5 wasn't just a folder choice. It was a security calculation. Here's what six weeks of daily commuting taught me.
Quick specs at a glance
| Spec | DYU A5 |
|---|---|
| Motor | 250W |
| Battery | 36V 10Ah (360 Wh), removable |
| Range (pedal-assist) | 50 km |
| Weight | 22 kg |
| Unique feature | Remote lock (wireless key fob) |
| Price (EU) | €519 |
Why the remote lock actually matters
Bike theft in European cities is a background anxiety most riders learn to live with. Heavy U-locks, frame locks, registered insurance, all of it. But the A5's remote lock is a category I hadn't encountered before — a key fob that arms and disarms an electronic lock on the bike itself. When armed, any movement of the bike triggers an audible alarm.
Three things this has actually done for me:
- Daily lunch-time check disappeared. I used to walk back to the bike rack between classes to make sure my bike was still there. Now I arm the alarm, walk away, and trust the system. If something touches the bike, I'd hear the alarm from the classroom.
- Physical lock got lighter. I still use a cable lock through the frame to the rack, but with the alarm layer I downgraded from a 2 kg U-lock to a 400g cable. That's daily quality-of-life improvement carrying the bike up stairs.
- One legitimate test. Week three, I left the bike outside a café in the 5th district while I grabbed a quick espresso. Came back ten minutes later — alarm had triggered. Somebody had tried to move the bike. No damage, they'd walked off. Would the cable lock alone have been enough? Maybe. Would I have known they tried? No.
The remote lock doesn't replace a physical lock. It layers on top of one. That layering is the thing most folders don't offer at this price.
How the A5 rides
Beyond the lock, the A5 is a competent 20-inch folding pedelec. Magnesium alloy frame keeps the weight to 22 kg (not 30+). 50 km range on pedal-assist covers a full week of my 7 km each-way commute without charging. The ride is direct, responsive, not refined like a torque-sensor bike but not wooden either.
Specific ride impressions after 42 days:
- Acceleration from a stop is confident — the 250W motor kicks in quickly with cadence sensor response, plenty for catching up to Viennese tram traffic when a gap opens.
- Climbing the short hill up to Neubaugasse requires active pedaling. The A5 is an assist bike, not a throttle bike on climbs. Fine with me; I'm not looking for a moped experience.
- Braking is disc front and rear, consistent in Vienna rain. Not hydraulic like the C9, but competent.
- Stability on Vienna's cobbled sections (parts of the Ringstraße, side streets in the 1st district) is adequate. 20" wheels smooth out more than 14" would. Still not as planted as a full-size city bike.
Folding for apartment life
I live in a 42 m² apartment in the 6th district. Indoor folded storage isn't optional — it's the whole premise. The A5 folds in maybe 12 seconds once you've done it a hundred times. Folded dimensions are roughly 80 × 40 × 70 cm, which fits behind the front door without blocking the hallway.
Compared to a non-folding commuter bike I rode before: the A5 is in my apartment every night. That means zero theft risk from outdoor parking, zero weather exposure, and zero morning routine of negotiating the building's bike cellar. Those are small daily wins that compound.
The removable battery, actually used
Another A5 feature that sounded like a spec-sheet nicety turned out to be genuinely useful: the battery slides out. Three scenarios where this has mattered:
- Charging in the apartment while the bike stays in the hallway. Outlet is in the bedroom; bike lives by the front door. Battery goes to the bedroom, charges overnight, comes back in the morning.
- Second battery option. I haven't bought one yet but I'm tempted — two batteries would cover a full week without charging at all.
- Theft deterrence (again). On days when I'm parking the bike outside for longer than my normal commute stop — a doctor's appointment, an afternoon meeting in the 3rd — I pull the battery out and bring it with me. A powerless bike is a less attractive target.
What the A5 doesn't do well
Three honest trade-offs at this price point:
- Display is minimal. Battery indicator, speed, assist level. No Bluetooth, no GPS tracking, no app integration. For the price I understand the choice, but riders expecting a smart-bike interface should look higher in the range.
- Cadence sensor, not torque. For a rider coming from a torque-sensor pedelec, the A5's assist feels more binary. You pedal, it helps at the preset level. For short commutes this barely registers; for longer rides some riders prefer the more natural feel of a torque sensor.
- Remote lock has a learning period. The first week I triggered the alarm twice by accident — picking the bike up to reposition it while armed. You learn to disarm before moving. Not a flaw, just a habit to build.
Who the A5 is actually for
After six weeks I'd recommend the A5 specifically for:
- Urban commuters with outdoor parking concerns — the remote lock is the headline feature and it genuinely helps
- Apartment dwellers who need the folded bike inside but don't want to haul 30 kg
- Riders who want a folder at the €500 level and are prioritizing security over premium ride feel
- People who routinely park their bike in multiple public locations during the day
The A5 is less ideal for:
- Riders who garage-park privately and don't need the theft-deterrent layer
- Long-distance commuters who want more than 50 km range (look at the C9)
- Anyone who values natural pedaling feel above all else (the T1's torque sensor is better)
My verdict after 42 days
The A5 isn't the most refined folder in DYU's lineup. It isn't the lightest, fastest, or the one with the smartest display. What it is: the only folder under €600 I could find that addresses bike theft as part of the product, not just as an aftermarket add-on. For teaching at a Viennese Gymnasium with an outdoor rack, that single fact tipped the decision — and six weeks later it still holds up.
Frequently asked questions
How does the DYU A5 remote lock actually work?
A small key fob arms and disarms the system. When armed, the bike's frame alarm triggers if it's moved — picked up, wheeled, tilted significantly. Disarm before touching the bike and there's no alarm. The lock doesn't physically immobilize the wheels; it's a motion-triggered alarm that layers with a conventional lock.
What's the battery life of the A5's remote lock fob?
The fob uses a standard coin-cell battery, replaceable. I haven't had to change mine yet after six weeks; manufacturer suggests 6–12 months depending on use.
Is the A5 EN 15194 compliant for European cycle paths?
Yes — 250W rated motor, 25 km/h assist cap, EN 15194 certified. Legal on EU cycle paths (subject to specific country and local rules).
Can I ride the A5 in Austrian rain?
Yes, within reason. Standard wet-weather use is fine; avoid deep puddles and don't submerge the battery. After my six weeks including several rainy days, no issues. Wipe the charger port dry before plugging in.
How does the A5 compare to the DYU D3F?
D3F is lighter (19 kg vs 22 kg) and has cruise control but lacks the remote lock. A5 has the remote lock and a larger 20" wheel for a slightly smoother ride. Roughly the same price (€519 vs €699 depending on promotions and market). A5 for security priority; D3F for ultimate portability.
Ich unterrichte Mathematik und Physik an einem Wiener Gymnasium im 7. Bezirk. Seit Frühjahr 2026 fahre ich täglich mit dem A5 zur Arbeit und beschreibe hier meine Erfahrungen aus sechs Wochen Alltagsnutzung — inklusive der echten Diebstahlangst, die in Wien keine Kleinigkeit ist.
