Whats good for a beginner? Sizing? Spec? Its a whole new world from MTB! Educate me...
Just been through similar (wanting to buy but knowing nowt about BMX).
What budget????
At 10 years old a 20" wheel should do.
Top tube fit seems a bit of a minefield, google [i]bmx sizing[/i] and you'll eventually find a happy medium from the majority of answers
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or better still find your local rider owned shop and get them to advise.
I managed to get complete bike full CroMo frame & forks for £270 with a 20.6" top tube for my 173cm height, my 8 year old son got an 18" wheeled bike.
What area are you in?
Depends whether you want a race or a park/street bike too. If you have a local track and are going to take him/her there then a race bike will be best, but if it's for going to the local skatepark and/or playing around on the street a park/street bike may be better.
Typically park bikes are available with 16", 18" and 20" wheels, whereas race bikes mainly have 20"wheels and varying top tube lengths and handlebar heights.
Go for a race bmx as the sizings are better. ie not just top-tube but crank-length, bar width and height. How tall is your lad?
Must run the ruler up him later when he comes home! It will be for street/park type stuff as we dont have much of a race scene here (in NI). Thinking an 18inch wheeled bike will suit him best, we do have CRC so will take him into the shop and size it with him. Thanks.