When my son's Huffy Green Machine Slider Bike broke, we turned it into an electric boat!
We removed the back wheels and then connected the frame upto two long stormwater PVC pipes.
It was very simple to add an electric outboard motor and attach it to the steering arms.
Sam then had a great time down at the lake!
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https://www.youtube.com/watch?v=bnilfMDJnB4