To extend to four bikes, an extended rail holder is attached to the bike carrier. Both the 3rd wheel rail and the 4th wheel rail are then bolted to it. The third bike is attached to the frame as usual with a frame holder, the fourth bike is attached to the third bike with a double frame holder from frame to frame.
The lock number can be selected to match your other keys. Please note whether you have a key with a black plastic cap or a completely silver key. You will find the locking number either on another key or on the locking cylinder.
The extension increases the weight of the carrier by +4 kg.
New total BackPower weight for 4 bikes: 23 kg.
(all weights +/- 5 percent).
