I bought a carerra tdf road bike as my first road bike and i took it to halfords for a service and they broke the left 16 speed Shimano ST-2300 shifters, when i try to move the chain onto the larger ring it will move but the it doesnt click and the second i let go it moves back to the smaller ring... ive seen many cheap replacement sti shifters on ebay however i dont know which ones will fit my bike i was wondering if anyone here could help my out as im not very experienced with this sort of stuff.. kind regards.

Welcome to Bike Forums. I'm sorry to hear of your broken shifter. However you have posted your question in our Introductions Forum.

Please post your question in our Bicycle Mechanics Forum. Bicycle Mechanics

welcome to the forums...as suggested, put your question in the mechanics forum to get the assistance you require.