Answer:
The answer is the tire went flat
Explanation:
When we have two or more events happening at the same time, we should be using the same verb tense to express it.
From the given sentence, we see that riding the bicycle and the tire going flat happened one after another, so both verbs should be in the same tense. However, we have the verb rode which is past tense and the verb goes which is present tense. Occurrence of these verbs in different tenses is called verb shift and it is usually considered a bad grammar, so to correct it we need to change the verb goes to its past simple form because both of these activities happened in the past.
