The car parts and bike business said its annual pre-tax profit lifted 1.1% to £72.8 million, beating market expectations. Shares rose more than 9%.
Chief executive Matt Davies said children's bikes sold strongly during the festive period, while the group refreshed its premium range of bikes, some of which are designed in conjunction with Olympic cyclist Chris Boardman.
The firm said its bike sales grew 19.4% on a like-for-like basis over the year, aided by upgrades to its Apollo and Boardman range of cycles. In recent years the business has also benefited from the success of British sporting heroes such as Sir Chris Hoy, Sir Bradley Wiggins and Victoria Pendleton.
The Worcestershire-based business is in the middle of a three-year investment programme that will see it spend £100 million by the end of 2016 upgrading many of its 465 Halfords stores and its 303 Autocentres garages.
The business spent £30.4 million last year on capital investment, which included refitting 23 Halfords stores and upgrading equipment at Autocentres. The group plans to refit another 50 Halfords shops over the coming financial year.
The business also relaunched its Halfords website in November, which grew by 17.7% over the year, and now accounts for 11.3% of the firm's overall sales.
The firm said group sales lifted 7.9% over the period, while sales at its Autocentres rose 8.6%.
Analysts at Investec raised their pre-tax profits guidance for 2015 by 7% to £75.8 million and said they expected Halfords to show "good sales momentum" over the summer.