Bikes
Duotts C29 : test / review
Published on: 21-06-2025 / Modified: 21-06-2025
Up until now, I'd tested fairly heavy (fatbike type) and fairly light (carbon frame type) bikes, but not yet a motorized mountain bike. I hadn't yet tested a Duotts bike, so this was my chance to kill two birds with one stone by testing the Duotts C29.
The Duotts C99 is a mountain bike with a 15 Ah battery and 750 watt motor, so it's lighter and less bulky than a fatbike without sacrificing performance. This Duotts C29 is undoubtedly the bike with the best price/power ratio. It has a lot going for it, but there are a few things to be aware of before you buy. I'll tell you all about them in this new test
Promo code
The Duotts C29 is available at the best price on the official website. Stock is available in Europe, so there's no extra tax to pay and delivery is fast
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Duotts C29 / Duotts.com
Manufacturer web site:
https://www.duotts.com
Special offer
https://duotts.com/products/c29?ref=LAURENTTimeline
Unpacking
The Duotts C29 comes in a large box like most bikes. Everything is very well protected by foam pads. The whole thing weighs just over 30 kg, so you may need the delivery man to help you get the box into your home.
The bike is so tightly packed that it will take you almost as long to detach all the protections as it will to assemble the bike.
Assembly is fairly easy on the whole, with the manual covering the most important steps without going into detail on every stage. So if you need more information, Duotts has actually made a video to help you with assembly:
Duotts assembly and manual
The bike comes with a number of accessories:
- fenders
- luggage rack
- front/rear lights
- charger
- reflector
- pump
- allen keys
Specifications
| Feature | Detail |
|---|---|
| Model | Duotts C29 |
| Motor | Brushless 750 W (65 Nm) |
| Battery | Li-ion 48 V, 15 Ah (~720 Wh), removable |
| Charging time | 6–8 hours (charger 54.6 V 2 A) |
| Max speed | 25 km/h (limited) – up to 50 km/h in unlocked mode |
| Range | 50–60 km in 100% electric mode, 80–100 km with pedal assist |
| Frame | Aluminum alloy |
| Front suspension | Aluminum suspension fork, 100 mm travel |
| Transmission | Shimano mechanical, 21-speed |
| Brakes | Mechanical disc brakes, 160 mm rotors |
| Handlebar | Multifunction, with 5-level LCD display + Bluetooth |
| Tires | 29" × 2.1", tubeless ready (with inner tube) |
| Net weight | 26.5 kg |
| Gross weight (packaged) | ≈ 31–31.7 kg |
| Dimensions (L × W × H) | 184 × 71–71.5 × 113 cm |
| Saddle height | 85–103 cm (adjustable) |
| Wheelbase | 113 cm |
| Max load | 120 kg (150 kg depending on version) |
| Max climbing angle | 30° |
| IP rating | IPX4–IPX5 |
| Operating temperature | -10 °C to 40 °C |
| Lighting | Front headlight + integrated rear light |
| Accessories | Front/rear mudguards, luggage rack (25 kg), aluminum pedals, USB charging port, lock, pump, tools |
Overview
The Duotts C29 is an electric mountain bike that will appeal to a wider audience than off-roaders. Price will obviously play a big part in the success of this bike, but it's not the only factor. The Duotts C29 is considerably less bulky than a fatbike, taking up no more space than a mountain bike without a motor
Its weight is still quite substantial compared with a normal mountain bike - it weighs 26.5kg, but that's considerably less than a fatbike. By way of comparison, a Decathlon mountain bike (Rockrider type) with 29-inch wheels and no motor weighs around 15kg. The motorized version of the Decathlon mountain bike weighs about the same as the Duotts. So we're really in a similar niche, but Decathlon electric mountain bikes are much more expensive.
Frame
The Duotts C29 is a classic aluminum frame. If it didn't have a battery compartment, it could be mistaken for a non-motorized mountain bike frame.
The minimum seat height is 85 cm and the handlebars are at 108 cm. With an incline like this, we're not on a bike to ride with an aggressive posture. The posture is upright and more restful for the back than on a bike without this inclination. This comfort advantage diminishes with your height, as the handlebars are not height-adjustable. If you increase the saddle level, you'll modify the position to create more pressure on the arms.
I'm 1m94 tall and I had to raise the saddle by 16 cm. My seat level is now more than a meter off the ground and I find myself in a position very similar to a normal bike. I'm used to this kind of position, so it doesn't bother me, but it does mean that I'm more likely to feel fatigue in my wrists after a long ride.
Handlebar
The handlebar is 68 cm wide, so it should be able to pass through any type of door. I find it rather cluttered because on the left there's the screen and on the right there's a phone charger, which ideally still needs a phone holder. So I had to move the equipment around a bit to fit my camera and phone
The handles are made of plastic, and they're pretty hard. So if you're leaning heavily against the handlebars because of your height, you'll feel some wrist fatigue. There are two separate gear levers, as this bike has a three-stage crankset and 7 gears on the derailleur.
The idea of adding a phone charger on the handlebars is interesting, but I find it takes up too much space, especially if you want to add your phone on the handlebars.
Unlike fatbikes, the brakes are not reversed.
Engine
The Duotts C29 is equipped with a 750-watt motor that develops 65 Nm of torque, more than enough power for the vast majority of the population. This motor, combined with the 21 gears, will enable you to find the right gear to tackle just about any type of climb.
I'll come back to the motor's performance in detail later in this test, but I can already say that it has a little latency when starting up, like I had with the Lankeleisi RV800 Plus, which was also equipped with a 750-watt motor.
Crankset/Cassette
The crankset has a three-stage configuration of 48, 38 and 28 teeth. This is the first time I've tested an electric bike with so many steps. This configuration should make your life easier when it comes to climbing larger climbs, although it doesn't mean you don't have to pedal, of course, but you have a wide range of possibilities here for finding the right difficulty/speed ratio.
We find a Shimano 7-speed derailleur at the rear, as on many bikes, with 14, 16, 18, 20, 22, 24 and 28 teeth. Here, too, you have a fairly wide range of possibilities, and starting at 14 also gives an indication of the bike's orientation. It's not a speed-oriented bike, it's mainly there to make things easier for you when you're going uphill
With a 48x14 configuration and 29-inch wheels, you get a development of 7.84 meters per pedal stroke, so you get a speed of 28.2 km/h for a cadence of 60 rpm without taking motor assistance into account. If you go down a level to 38T on the crankset, you get 6.2 meters per pedal stroke and 4.57 meters with the 28T.
This configuration also prevents you from grinding too fast. If you're in 48T and riding at 25 km/h, you'll start to grind from 21T. If you switch to 38T, you'll start grinding at 18T.
Wheels
The Duotts C29 is fitted with 29" x 2.1" Chao Yang tires. These tires can handle pressures from 20 to 40 psi, but I'd advise you to aim for somewhere in the middle of these values. I tend to inflate my tires to the maximum but I can see here that the tire overflows the rim quite quickly and if you overinflate it you risk bursting the tube if the road is damaged. I inflated the tires to 30 and I think that's more than enough, despite my weight of 100 kg.
Suspensions
The front suspension has a very wide 8 cm travel, so you should be able to take a lot more shock, especially if you're leaning on the handlebars. It's probably not very useful on an urban course, but on cobblestones, this suspension does a good job.
There's no suspension at the rear, but tire pressure can play a role here (up to a certain limit), and the saddle also provides a good level of comfort, but won't replace the comfort of suspension in the wheels, frame or saddle. As I don't think this bike is intended to be abused on rough terrain, the absence of rear suspension shouldn't be a big problem.
Brakes
The Duotts C29 is equipped with non-hydraulic disc brakes, so the braking is less effective, but I see that it's possible to order hydraulic brakes and install them yourself. There's a video explaining how to change the brakes on the page with the user manual I shared earlier in this review.
Saddle
The saddle looks pretty classic, but it's got a few things going for it. It's not as big as that used on fatbikes, but it has a structure that absorbs shocks quite well. There are no springs or suspension, but it's comfortable. The other positive point is the length of the seat tube. As I'm 1.94 meters tall, I sometimes run out of height for the seat tube.
So I had extended the seat tube quite a bit during assembly to make sure it was long enough. In fact, I had to quickly reduce the height because I couldn't ride the bike anymore. I ended up with a 16 cm gap with the frame, which is very little compared to the length of the seat tube. So this bike is very well suited to tall people (over 2 meters). Just bear in mind that, as the handlebars are not adjustable, the riding position may not be very comfortable if you're very, very tall (over 2 meters).
Battery
The Duotts C29 is equipped with a 15 Ah, 48V battery. I find this battery rather unattractive; it's very imposing in relation to the bike's frame, and you can see that it's been grafted into the frame rather than integrated as on other bikes. It almost gives me the impression that this bike was originally a normal bike with a battery attached. It's not very pretty, but I'll leave it to you to decide whether you like this type of integration or not
The battery life should therefore be around 35-40 km, riding at full throttle all the time and with a person of my weight. The battery has an integrated charge indicator. I find this quite handy, as it lets you see what level of battery you're at, and when you're charging it, for example, it means you don't have to charge it all the way. There's also an ignition button and keys to dislodge it from its cradle
I measured 102.9 watts at charge level. This will bring charging time to over 7 hours, bearing in mind that the last few percent will take longer to charge than the first few percent.
Screen/Control
You can control the bike in several ways. The easiest way is to use the display on the handlebars. This screen gives you an indication of your speed, range (in battery percentage), mileage and assistance level. Although this display is well designed, it has very poor legibility in bright light. To make it legible, you need to increase the brightness in the settings and turn it towards you. This legibility is really problematic if you're not using a phone
The assistance level change works well, but I find that the positioning of the buttons in relation to the handle is not optimal. If you also tilt the screen to make it readable, access to the buttons will be even more difficult. Buttons like these should be located as close as possible to the handle. You can loosen the screen to move it to the left
The other option for controlling the bike is the Duotts app. This app will allow you to manage the level of assistance, track your bike's journeys, participate in the community and get an accurate battery level figure. I didn't expect to have an app for a bike in this price range, and I think it adds a significant plus to the bike. The app means you don't have to rely on the screen on the handlebars, and it gives you a more accurate view of the battery status.
Accessories
The Duotts C29 is a well-equipped bike, and it looks like you won't need any additional accessories. There are two mudguards, a luggage rack, front and rear lights and reflectors. I just find that the mudguards are a little too flexible, and the attachment system doesn't keep them in place. As a result, you'll hear the mudguards rattle if you're riding on an uneven surface. I have the same problem with most of the bikes I test, the cases where the mudguards are metallic and attached are quite rare.
Road test
Motor opinion
For the road test, I use a series of measurements to compare the bike's performance with other bikes I've tested. Even if some bikes aren't comparable, the effect on effort or fatigue is very real, and that's what we should remember rather than the pure performance figure
This bike is equipped with a 750-watt motor, and this motor delivers sufficient power for a large majority of users. The combination of motor power and the number of gears available should be able to meet all your needs; you'll always find a combination that suits you, so this bike offers great flexibility.
To take full advantage of the motor, however, you need to be aware of a number of things. Full power is not available at all assistance levels, and I find that the first assistance levels are rather weak. To get the most out of your bike, you need to be on assistance level 4 or 5. You also need to take wheel size into account, because with 29" wheels, you're increasing inertia quite a bit, so the starting effort is greater. This effort will be felt even more with the latency of the assistance. As with the Lankeleisi RV800 Plus I tested, the assistance doesn't kick in instantly, so you'll feel like you have to push hard to get going.
I'm used to riding as much as possible in the hardest gear, and with this bike, I had to change my habit a little to cross roads, because with the latency and inertia, I wasn't responsive enough to cross. So I'd advise you to do the same, choosing a lower speed and possibly adapting the motor's sensitivity in the settings.
This bike also has a cruise mode that allows you to push the bike up to a certain speed with minimal effort, this mode will allow you to avoid inertia and latency. If you decide to install the throttle, this will no longer be a problem, as with the throttle the bike can start without assistance and run up to its maximum speed.
In short, to get the most out of the motor, you need to start at a lower speed, use cruise mode and/or adapt the sensitivity level (parameter 11)
Opinion on crankset/cassette
As I've mentioned several times in this review, the crankset and derailleur configuration offers greater flexibility of use, and is clearly one of the bike's strong points. On the other hand, I find that gear shifting isn't super-smooth; I get the impression that the lever isn't as well notched, and that the precision is therefore less. I also had a lot of chain misfires on my first few kilometers, and had to tighten the derailleur cable to prevent this from happening again. After this adjustment, everything went smoothly. The cable may have been a little loose during transport, but if that happens to you, it's very easy to fix.
Brake test
This bike is fitted with mechanical disc brakes, so this type of brake is less efficient than a hydraulic brake. I measured the braking time from 25 to 0 km/h with the rear brake alone, and obtained a time of just over 3 seconds. With both brakes, braking is much more efficient, at just under 2 seconds, leaving a nice tire mark on the road. For braking in normal conditions, finding the right dosage for the rear brake is a matter of habit, but the combination of the two brakes remains the safest method.
I see on the Duotts website that it will soon be possible to order hydraulic brakes if you need more powerful braking.
Speed/acceleration test
I don't dismount my bikes when I do my test because it would completely change the result of the measurements from one bike to another. If I test this bike freewheeling and unconstrained, I can see that it can go up to 50 km/h without any problem, which will probably translate into a speed of around 45 km/h on the road. With this kind of speed, this bike will have to be considered as a moped
If I go back now to my usual test, I was able to get a speed between 35 and 40 km/h against the wind on my 2.5% descent, which is an excellent result. The bike is very stable and I never felt any stress at this speed. On the flat, and with the most difficult gear, I manage just over 30 km/h. With the size of the wheels, the effort required is greater, and this bike is not designed for speed unless you install the throttle and disengage it.
If you choose to disengage it, this bike will undoubtedly be one of the fastest bikes in its price range.
Climb test
For my uphill test, I have a 2.5% climb that stretches over 690 meters, which I use for all my bike tests. I first ride this climb without assistance and with the hardest gear, trying to stay at 25 km/h the whole way. I then do the same thing with the first assistance level and then the last
Level 0 (unassisted):
1:48
167 pulses max
23 km/h average
Level 1
1:53
165 pulses max
21.9 km/ average
Level 5
1:33
145 pulses max
26.7 km/h average
As you can see, I went faster without assistance than with level 1. This test is not a laboratory test, so other factors may come into play, but this difference shows what I had already mentioned earlier in the test. The first levels of assistance don't bring much benefit. Level 5, on the other hand, provides very comfortable assistance, but here I get a higher number of pulses than other bikes, because the initial effort is greater (due to inertia).
Effort test
I tested all the assistance levels to see how long it took me to reach 25 km/h using the most difficult gear. Here are the times I obtained:
level 1: 15 seconds
level 2: 13 seconds
level 3: 11 seconds
level 4: 8 seconds
level 5: 6 seconds
So levels 4 and 5 are much more efficient than the others, especially if you want to enjoy going as fast as possible
I also tested this bike on one of my rides, I compared a 32 km ride with this bike and my (non-electric) racing bike. It was very windy in both cases, but as always, I do the course to the maximum of my ability every time
Racing bike
Course time: 1:18:11
Max pulse: 172
Average pulse: 153
Average speed: 24.6 km/h
Max speed: 49.1 km/h
Duotts C29
Time: 1:15:30
Pulse max: 166
Average pulse: 146
Average speed: 25.2 km/h
Max speed: 44.5 km/h
On this 32 km route, which was quite varied, I used 20% of the battery. The average speed is a little higher than with my racing bike, but the difference isn't huge. It's mainly in terms of average heart rate that the difference is felt, with much less fatigue. The effort required with the Duotts isn't zero, you still have to pedal a bit, but I find its weight quite manageable with this engine power. I found it very nimble and, above all, much more comfortable than my racing bike
Suspension test
I've got a few cobbled roads near me, and while they're not Paris-Roubaix big, they're irregular enough to seriously shake you up, especially when you take them downhill. Obviously, without rear suspension it's less comfortable, but I found it quite acceptable. With the right tire pressure and comfortable saddle, this bike really limits the damage. The front suspension, on the other hand, is very effective, and to get the most out of it, you could lean a little more on the fork than on the saddle, which is a riding position perfectly suited to this type of bike.
Battery range
The battery is huge, but its capacity is inferior to the Lankeleisi models I've tested. However, the autonomy is really good. As the best way to get the most out of the bike is to use assistance mode 4 or 5, I thought I'd soon find myself without a battery, but I didn't
For my first 14 kilometers, I used up 20% of the battery, which would have given me a range of 70 kilometers. I then did a more varied 32 km run where I also consumed 20% of the battery, so I could have exceeded the 100 km mark with this type of run. If, on the other hand, I look at what I did for my engine tests, where I rode 12 km regularly pushing the bike hard, I lost 27% battery. So I think you can reasonably exceed a 40 km range by using the assistance a lot (keeping the clamping), but if you alternate pedaling and assistance, the range can go up to 100 km and maybe even a little more.
Trail test
Conclusion
Strengths
Weaknesses
LAURENT WILLENHead of myself on this blog
I share my passions on my blog in my free time since 2006, I prefer that to watching nonsense on TV or on social networks. I work alone, I am undoubtedly one of the last survivors of the world of blogs and personal sites.
My speciality? Digital in all its forms. I have spent the last 25 years working for multinationals where I managed digital teams and generated revenues of over €500 million per year. I have expertise in telecoms, media, aviation, travel and tourism.
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