Drawing wheels

As more and more students have reached the hallowed halls of lesson 7, I've been able to identify certain areas of weakness that need to be covered in order for the lessons to be more effective. This challenge serves as one of them.

I recommend tackling this challenge only after you have completed lesson 6, as well as the cylinder challenge, but before you attempt lesson 7.

Wheels serve as both a difficult aspect of the already significant challenge of drawing cars, but also an interesting summary of what makes cars so difficult. Each and every wheel has a sort of specific character, made up of a series of curves and irregularities in their forms that pertain to each model and make. As such, deviating even a little from this specific combination can make a drawing seem off without fully understanding why.

So, before we tackle the hell that is drawing cars, lets take some time to play with wheels instead.

Also worth mentioning: You are welcome and encouraged to use a ballpoint pen instead of a fineliner for this challenge, along with an ellipse guide if you have one.