Easy, Chain Reaction Cycles which is based in Northern Island (United Kingdom) is the world’s biggest bike store and reported a 2012 turnover of £170 million and are a top 10 UK online retailer. They are followed by Wiggle who have a smaller but enviable 2012 recorded turnover of £140 million.
In 2011 Chain Reaction Cycles reports sales outside of the European Union at 39% which is £66 million. For more information, a case study by a supplier provided more historical and financial information: Export Technologies: Chain Reaction Cycles Case Study
The leading bike shop shares their formular for success:
Traffic x Conversion Rate x Average Order Value = SALES
*Turnover values vary from source to source, some values provided are much lower however Chain Reaction Cycles leads.