Duotts C29K: more energy, the same basic platform

The C29K builds on the popular C29 with a second battery and hydraulic brakes. These are useful improvements, not a complete redesign. The basic frame looks dated, the components remain entry level, and the powerful motor encourages brisk riding. It suits someone who knowingly prioritises energy capacity and acceleration over refinement.

How the two batteries work

The removable packs are rated at 48 V 15 Ah and 48 V 22.5 Ah. Their combined nominal energy is 1800 Wh, calculated from voltage and capacity. Only one pack supplies the motor at a time. Select it manually with the switch beneath the rear rack, preferably after stopping. There is no automatic changeover or simultaneous discharge. The tested package included two chargers; the separate locks use different keys.

Range: estimate, not a measured discharge test

The reviewer estimates around 130-140 km of gentle riding using both packs. This is not a completed full-discharge test or a guaranteed distance. Less frequent charging on regular trips is the clearest benefit. Speed, climbing and load affect consumption, so keep a reserve when planning routes.

Strong assistance, limited finesse

The cadence sensor engages quickly, but the tested bike accelerated abruptly. With the limiter removed, assistance levels behaved more like speed targets than subtle support settings. The reviewer reached approximately 55 km/h on non-public land. This describes one unlocked test bike, not every version or a recommendation for public-road use. The manufacturer distinguishes 250 W EU and 750 W International versions; check the actual configuration before buying.

Improved brakes, basic running gear

After adjustment and bedding in, the hydraulic brakes worked well and outperformed those on the mechanical-brake C29 previously tested. Initial braking was weak, so proper preparation matters. No stopping-distance measurement was provided. Shimano Tourney components and the basic front fork do not make this a refined technical-trail bike.

Battery capacity cannot fix riding position

The rear pack restricts saddle lowering and fore-aft adjustment. Its metal housing also obstructs swinging a leg over the bike; the reviewer hit it several times and once cut his leg. The stretched position loaded his hands and back on longer rides. Try the bike with both packs installed, particularly if you need a low saddle or easy mounting. The reviewer’s comment about roughly 185 cm is a personal fit impression, not a universal height limit.

Details that need work

The display had poor viewing angles and occasionally dimmed or interrupted operation when its angle was adjusted on the test sample. Plastic mudguards rubbed against the tyres over bumps and needed repeated adjustment. The non-indexed front shifter requires careful positioning to avoid chain rub. These practical shortcomings remain despite the extra battery.

Who should consider it?

An experienced C29 rider who likes its character but needs more energy for long regular trips is the strongest match. Expect some adjustment work and less natural assistance. Delivery riders may appreciate the capacity, but frequent mounting and a delivery box can make the rear battery obstruction more troublesome. For relaxed leisure rides, a first e-bike or easy access, a different design makes more sense.

Verdict

The published review score is 6.1/10. This is a longer-working C29 with a worthwhile brake upgrade, not a thoroughly modernised model. The upgrade makes most sense when you will genuinely use the second battery. Capacity alone does not compensate for the limitations if comfort, smooth assistance and refined equipment matter more.

Questions and answers

Do both batteries power the motor together?

No. Select one pack manually; the bike uses one power source at a time.

Was 130-140 km measured?

No. It is the reviewer’s gentle-riding estimate, not a full discharge test of both packs.

Does it have a torque sensor?

No. The tested bike uses a cadence sensor with abrupt assistance.

What changes compared with the C29?

An additional 22.5 Ah battery and hydraulic brakes. The geometry and many basic components remain similar.

Is it suitable for a shorter rider?

A fitting session is essential. The rear battery restricts saddle lowering and obstructs mounting.

What does the JOTEM code save?

The review provides the code but contains conflicting discount amounts. Check the actual saving at checkout.

Differences you will genuinelynotice while riding.

Comparison verdict

Differences you will genuinely
notice while riding.