Was having a problem trying to remove battery.so I put some fishing line on the flapper too lift up the flapper.i bet some thread will work too but didn't have any
https://www.amazon.com/Sunlite-Flame-Tire-3-0-Black/dp/B000AO5IN0/ref=sr_1_5?keywords=20x3+Bicycle+Tires&qid=1636986882&sr=8-5
here's some slick ones i found on amazon