25-30 reps and 5 sets is A LOT of volume for anyone. In theory, the amount of time/reps that you're under the weight should translate well into sprint training. However as a workout, it's so much volume that it might be difficult to recover from after awhile. In practice, I happen to think it's not too useful going over 20 reps, because any more than that starts to become metabolic conditioning, and less strength training. I've learned both here and in an academic setting that weights are for strength conditioning, and the bike is for metabolic conditioning.
If I recall from some of your other posts, you're pretty young (correct me if I'm wrong) and probably haven't been exposed to a weight training program before. I highly recommend Starting Strength. As a novice to strength training, you have greater potential to adapt to a training stimulus and become stronger than a more advanced lifter, and this program makes great advantage of that. Be sure to keep in mind though, that you're racing bikes, not competing in powerlifting competitions. Some say that weight training lowers your leg speed, though I disagree. Whether that's true or not, don't sacrifice your sport specific training (on the bike) for better numbers in the gym.