The Koolux BK6S 4 0 is a folding e-bike that stands out for its price. At 852 USD, it is 20% below the median for its type. That makes it one of the more affordable folding bikes in our database.
It has a 624 Wh battery and a hub motor. The manufacturer claims a range of 45 km, and our estimate matches that. It is a standard pedelec, so it assists up to 25 km/h. This bike suits commuters who want a low-cost way to get around and need to store it in a small space.
What the numbers say
| Spec | This bike | Median for its type |
|---|---|---|
| Battery | 624 Wh | 672 Wh |
| Weight | 33.1 kg | 28.6 kg |
| Torque | Not listed | 50 Nm |
| Estimated range | 45 km | 48 km |
| Price | 852 USD | 1068 USD |
Questions people ask about the Koolux BK6S 4 0
How much does it weigh?
The Koolux BK6S 4 0 weighs 33.1 kg. That is 16% above the median for folding bikes. You will feel the extra weight when carrying it up stairs or lifting it onto a rack.
How much torque does it have?
Torque is not listed for this bike. Many folding bikes in its class have around 50 Nm, but we cannot confirm the BK6S 4 0's figure. If torque matters to you, check with the manufacturer.
What speed class is it?
It is a standard pedelec, so it assists up to 25 km/h. You can pedal faster, but the motor stops helping at that speed. This is typical for its class.
How far does it really go?
Our estimated range is 45 km, based on a reference ride. That estimate is in the band from 39 to 50 km. The manufacturer claims 45 km as well, but we do not compare our estimate to claims because test conditions differ. Use the range calculator to see how your weight and terrain change the estimate.
What does it cost to run?
Running costs depend on electricity, maintenance, and how often you replace parts. The battery is 624 Wh, which is small but adequate for short trips. Use the cost calculator to estimate your yearly costs.
Where it falls short
The Koolux BK6S 4 0 is heavy. At 33.1 kg, it is 16% above the median for its type. That extra weight makes it less nimble and harder to carry.
Who should buy it
This bike fits budget-conscious riders who need a folding model. It is not for those who prioritize light weight or high torque.
- You want a low-cost folding e-bike for flat commutes.
- You have a place to store a heavier bike and do not need to carry it often.
- You are okay with a standard pedelec speed limit of 25 km/h.
Look elsewhere if you need a lighter bike for carrying, or if you want more torque for steep hills. The BK6S 4 0 does not publish torque, so it may not suit demanding routes.
