The robot standard wheels are 70 mm wide, made of plastic. There is an option to use narrow wheels if you have narrow aisles in your stables. These narrow wheels are 35 mm wide which means the robot will be 70 mm narrower in total.
If your robot has the 35 mm wheels you should know that it could effect the friction against the floor due to less contact area, specially on very dirty floors (the wheels slipping, leading to incorrect position).
Since the robot gets 70 mm narrower with the 35 mm wheels it could effect the balance of the robot sideways when it washes far out with the telescope combined with uneven/sloping floors.
Flexi-wheel 70 mm = 680 mm wide
Flexi-wheel 35 mm = 610 mm wide
The guidance wheels are supposed to be soft so they can swallow obstacles on the wall in the aisle, like doors/gates or similar. Soft wheels will make it easier for the robot to have an even travel along the aisle. However, all stables and aisles don't look the same. If the aisle have doors/gates that sticks out too much, the robot might have a too heavy hit when trying to climb over the obstacle. This could lead to slipping wheels that leads up to incorrect positioning for the EVO Cleaner. It can also lead to "Wheels stuck in forward/backwards direction".
Having problems? Check the following list:
There is a lot that comes into play when it comes to guidance wheels and what's possible and what's not.
Things to consider:
For help with the choice of wheels, please see Aisle and robot measurements