Here is what I would do to make your bike race-ready without spending too much money:
Day of Purchase
The first upgrade you need to make is going to clipless pedals. You should do this immediately, because it’s a huge performance upgrade!
Most bikes in this price range either have flat pedals, no pedals at all, or maybe the basic Shimano SPD pedals. (If they do come with a pedal like the Shimano M520, you can use that to start, but be prepared to upgrade eventually, as these pedals don’t always work well.)
If the bike comes without clipless pedals, I would recommend looking at nicer pedals from Shimano, Time, and Crank Brothers. Popular models are the Shimano M770, Time ATAC XS Carbon, Crank Bros Eggbeater SL, and Crank Bros Candy SL.
You will also need special shoes to go with the clipless pedals. Take a look at models from Shimano, Sidi, Northwave, Specialized, Bontrager, Diadora, and Pearl Izumi. (Consider some more cycling clothing while you’re at it.)
Most bikes in this price range either have flat pedals, no pedals at all, or maybe the basic Shimano SPD pedals. (If they do come with a pedal like the Shimano M520, you can use that to start, but be prepared to upgrade eventually, as these pedals don’t always work well.)
If the bike comes without clipless pedals, I would recommend looking at nicer pedals from Shimano, Time, and Crank Brothers. Popular models are the Shimano M770, Time ATAC XS Carbon, Crank Bros Eggbeater SL, and Crank Bros Candy SL.
You will also need special shoes to go with the clipless pedals. Take a look at models from Shimano, Sidi, Northwave, Specialized, Bontrager, Diadora, and Pearl Izumi. (Consider some more cycling clothing while you’re at it.)