Get Your Ride On!
Find out what kind of cycling you want to do and get a bike that’s specific for that. Get the bike fitted properly at the shop, especially if it’s a road bike. Clipless pedals (for road or mountain) are a big help. It’s almost like having an extra leg when you completely take advantage of them. Do a thorough research before buying anything.
Don’t worry so much about weight, it’s a myth. The only place where weight will be important is at the wheels. Heavy wheels in road bikes can slow you down a little…but this is only important when you’re really serious. In a mountain bike, weight is even less important since you’re more worried about durability.
The budget depends. A good road bike can start around $ 700. Hardtail mountain bikes go from about $ 400 up. Dual Suspension MTB starts at $ 1000. You don’t HAVE to have dual suspension. It just makes things a little nicer when you’re going over roots and keeps the rear wheel on the ground. But it’s not something that can decide a race. The front suspension does make a difference, however. Research the suspension forks.
When you start riding, don’t worry so much about training. Just have fun. You may notice your legs getting smaller at first. That’s just fat going away. Then the muscle will come in.
There are ways to train for events. But it all depends on the riding you will be doing.