icyclist 

My suggestions among so many good ones, for riding faster up the hills, based solely on my experiences over the years:

1) Lose some weight. Specifically, five pounds or more. You have to lose an honest five pounds, not just because you didn't eat or drink as much water as the night before. That will not be easy. If you exercise more to lose the weight, you'll just be more hungry. If you don't exercise more, and you eat less, you'll be just as hungry, because your body, in each situation, is going to want to replace the energy you lose. However, getting weight off your bike won't be as effective as getting weight off your carcass. Keep a food diary, eat a little less over time. How much time? Well, that's up to you, but it probably will take weeks, not days.

2) Couple the weight loss with more uphill riding – by yourself is fine – than you're currently doing. You're riding 2 or three days a week. That's not enough to improve your speed and strength. You will, in fact, gain weight initially as you up your workouts. You'll more than make up for that if you are also sticking to your diet, cutting back a little on your food over time. Are you eating dessert after dinner? Sugary snacks? Soft drinks with sugar? Don't, at least until the pounds are off.

You may never be able to be as fast as your younger friends – how old are you? – but you will be faster if you lose at least five pounds and up your uphill miles.

As you now realize, new wheels and/or getting a new bike won't make you that much faster. On the other hand, getting shiny new toys won't slow you down, either. They might add the motivation needed to push harder, and eat better, if you already doing that.