Present Conditional (e.g.: yo hablaría)

Questions about the Conditional:

Q: Why is it Si yo tenía and NOT Si yo tendría?

While the word si does suggest a condition or the notion of "maybe", it is not followed by the conditional form of the verb, nor is it followed by the present subjunctive. Other verb forms can be used, depending on the intended meaning, e.g.: the present (si mi amigo viene), the imperfect (si mi amigo venía), the preterite (si mi amigo vino), the future (si mi amigo vendrá), or the imperfect subjunctive (si no fuera por eso).