The Dual Motors are the top boat engine in How to Fish, and they turn the slow trip between islands into a quick hop. The upgrade lives in an easy-to-miss spot on the fourth island, tucked away from the main path, and it costs a fair amount of cash.
Quick answer: Sail to the fourth island, the one that holds the Lucky Bait Casino, walk around to the beach behind the casino, enter the small red shed, and buy the Dual Motors for $860.
Where the Dual Motors shed is on the fourth island
The boat upgrade shop is not inside the casino. It is a small red shed sitting on the beach directly behind the Lucky Bait Casino on the fourth island. Once you dock and head around the back of the casino building, you will find it near the sand.
Inside that shed you can buy all three boat upgrades in the game, including the Dual Motors, so this single stop covers everything related to boat speed and navigation.
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You will know it worked when the shed entry for the Dual Motors switches to “Already Bought” and your boat moves noticeably faster on the water. Buying it also unlocks the I am speed achievement.
Every upgrade in the red shed
The shed carries all three boat upgrades. The Big Motor and Boat Radar are cheaper add-ons, while the Dual Motors are the headline purchase.
| Upgrade | Price | What it does |
|---|---|---|
| Big Motor | $230 | First engine boost for faster travel |
| Boat Radar | $200 | Improves navigation between islands |
| Dual Motors | $860 | Best engine, top boat speed |
Note: The first engine boost, the Big Motor at $230, can also be picked up earlier on the Forest island and unlocks the Getting an upgrade achievement. You do not need to own it before buying the Dual Motors.
Should you buy the Dual Motors right away?
Speed is convenient, but the standard boat can still reach every island in the game. If money is tight, guns, weapon attachments, bait, and essential quest items are usually the better place to spend first. The Dual Motors pay off most once you are bouncing between islands to finish collections and achievements, when the extra speed saves real time on every trip.






