What are the requirements for a breach of contract?
It would be a matter of interpretation for the court to decide whether there was a breach of contract or whether the necessary acceptance existed to form a contract based on all the facts and circumstances involved. A written contract will typically specify how acceptance is to be made. In some cases, the obligation of the seller to deliver the good doesn't arise until payment in full is received. The answer will partly depend on the terms for payment and whether the failure to pick up the bike also involved a missed payment.
If a contract was formed and all agreed upon payments had been made at the time, the failure to pick up the bike may not be considered a breach of the terms that would void the contract. A material breach is required to void the contract. A material breach destroys the value of the contract and gives rise to an action for breach of contract. If all required payments had been made, it would be a matter of interpretation for the court to decide whether the failure to pick up the bike was a material breach or not.
An unjustifiable failure to perform all or some part of a contractual duty is a breach of contract. A breach may occur when one party fails to perform in the manner specified by the contract or by the time specified in the contract. A party can typically only recover those damages out-of-pocket to restore them to the position they would occupy if not for the breach. For example, a buyer may sue for return of a deposit or partial payment. A buyer generally can't order the seller to deliver the goods under the breached contract unless the item is of a special, unique nature such that no substitute is available.
A breach by anticipatory repudiation is an obvious indication that the party will not perform when performance is due, or a situation in which future non-performance is inevitable. A repudiation of contract terms is generally required to be affirmatively stated. An anticipatory breach gives the non-breaching party the option to treat such a breach as immediate, and, if repudiatory, to terminate the contract and sue for damages without waiting for the breach to actually take place.