One thing right away: The main difference between a hardtail bike and a fully bike is: The hardtail has no rear suspension. Due to the lack of a damper, this is "hard" or unsprung.
Basically, (almost) every bike can be converted. Some are easy to do, others need some adjustments. However, you should pay attention to a few things beforehand:
- Measure bottom bracket width, so that the appropriate motor can be selected
- Check battery location (where will the battery be mounted?)
- Determine suitable chainring, so that the chain line also fits after the conversion
The easiest conversion is usually done on a Hardtail, as these usually offer enough space for the battery in the frame triangle (1). Depending on how much the chain stay (2) is tapered, spacers may have to be added to mount the motor correctly. In addition, the chain line should be observed - to avoid a slanted chain guide after the bike conversion. We will publish a separate blog article on this. Furthermore, the geometry of the down tube is important in this area: With a hardtail, the down tube usually pulls upwards quite quickly. This ensures good ground clearance after the conversion. To choose the right mid drive motor, the bottom bracket width (3) must also be measured. This ensures, that the motor axle length matches the frame width of the bottom bracket.
Due to the rear suspension, Fully bikes usually have the disadvantage that no bottle mount battery can be placed in the frame triangle. Alternatively, this battery can be attached "hanging" on the down tube (see no. 3 in the following pictures). It´s also possible to use a custom made battery (for the triangle frame) or a backpack battery.
For Fully bikes, especially the frame geometry in the area of the bottom bracket should be observed. Then you can choose the right mid drive motor. On some bikes, the down tube usually runs horizontally in this area before it bends upwards (1). If you choose the Bafang BBS01, BBS02 or BBSHD mid drive motor, it will "hang" quite low because it can´t be turned upwards (bad ground clearance). If you ride mainly "onroad", this can be neglected. If you also ride your bike "offroad" and want to overcome obstacles, you will need more ground clearance and should choose a different frame - such as the following mark 2. With this, you will have more ground clearance. If you choose a CYC X1 mid drive motor, this is not of great importance, as this mounting concept allows to mount the motor inside the frame.
We hope this article has given you an idea of the conversion and also a comparison between the different geometries. If you have further questions, please feel free to contact us (email@example.com).
Have fun with your converted Bike!