One line from hub to rim — the wheel's supporting ray; and speech's past tense, a word already said.
Two separate Old English words converged in modern spelling — spaca (a wheel's spoke) and sprecan (to speak), whose past tense spræc gives the other sense — kinship in sound only, not in history.
One line running from hub to rim, carrying load outward evenly, and also a word already spoken, carried into the past tense. Two old words sharing one modern spelling by coincidence rather than descent.