The idea is good. bot the brushing is all wrong the chop looks dented and warped all over. the tires are way too small.I would strongly suggest watching basic tutorials and just focus on one thing on a chop until you get it right and then move forward. I would also recommend learning how to use the pen tool and feathering selections. good luck!
Have no fear of perfection, You will never achieve it! [Salvador Dali]