It was when you mentioned henlong that gave it away as to the problem, the henlong system is designed for their tank range and is preset to tank steer, there really isn’t much you can do with that as it’s the wrong type of esc for a boat.
My advice, live with it... but you can make your life a little easier by adjusting the servo to give you more rudder throw for turning at slow speed..
Here the thing tho... a lot of modern boats only go forwards and this is 99% of brushless setups as there are very few reverse escs available especially duel motor escs, only the rc car range have that ability and those tend to require a smart motor with a secondary plugin for the program of the motor itself.
Only other way around this is to swap out the esc, buy two mtronic escs, rated for the motors, disconnet one of the escs BEC central wire (usualy orange) and then Y harness them to the receiver. You can then singularly link both positives and negatives to a single connector for power.
This apply a to only brushed motors... brushless require two escs and two battery’s, one for each motor... no exceptions with a boating application due to the load draw, you can’t run a power distribution board like a drone in this instance, unless you are prepared to spend serious money on a very serious battery!
That’s all I got! Hope it helps!
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