Spokes with qcad.
First download and install QCAD professional trial from here. Probably the Windows 64 bit version or otherwise to suit your computer. It's the full Pro version of qcad but it only works in 15 minute bursts. It can be fully enabled by paying a fee, or downgraded to the Free Community Edition by following the instructions further down the same page:
QCAD Community Edition
If you are looking for the free open source QCAD Community Edition, you can download the trial version for your platform (see above) and then remove the QCAD Professional add-on running in trial mode (click Remove in the Trial widget and follow on screen instructions).
I think the Pro version is worth the money, but the Community edition is plenty powerful.
A qcad icon should appear on your desktop, or be found by typing qcad so windows can find it. Start QCAD.
A screen like this should open:

On the left hand side is a block of buttons, each opening a type of drawing tool, lines, circles, rectangles etc. Hovering the cursor over a button should display a short description.Start by drawing the wheel circles. Click on the circle button

And all the circle drawing buttons appear

The first three are the most common: draw a circle by pulling a radius with the mouse; draw a circle by typing a radius; and draw a circle by typing a diameter. Choose the diameter tool and a menu ringed in red will appear. These settings will draw a 50 unit diameter, full circle (0 degrees), positioned on screen from the circles centre. The circle is moved into position by the mouse and clicked. When drawing it helps to use snaps, which are shown in the green ring. Auto snaps to the nearest object. On an empty screen only grid points are available, more complicated drawings can snap to the end or mid point of a line etc

Plonk the circle anywhere convenient, then change the diameter to draw two more circles for the hub and outer wheel. Mine are 40 and 10 units in diameter:

Spokes will have to be tomorrow. The cat is demanding food with menaces!
Happy to answer questions.
Dave