In 1 ABY an adventurer fed the creature with Lokian weed. Speedbump only liked a special kind of weed, so the adventurer had to collect and try different plants to find the one Speedbump preferred.
Behind the scenes
The kusak is part of the Caring for the Kusaks collection. Each time a player finishes the Weed Whacker Foliage Requisition quest, the player is rewarded with one of ten different kinds of Lokian weed. These can be used to feed the kusaks, but each of the ten different kusaks in or near the stronghold only accepts one randomly determined kind of weed.