At UK regionals and nationals these bikes race in separate classes (i.e. 20” never race with cruisers). At smaller events, 20” and cruiser might be combined (whether there is a cruiser only class depends how many people are racing cruisers and whether enough cruiser riders fall within an age range that can be combined in a race class).
20” bikes are more common, and more readily purchased new or second-hand. A second hand bike in good working order can be bought for @£200 whilst new bikes start @£450 – you get better prices on new bikes toward the end of the year when dealers sell off old stock when the next year’s models arrive. Custom bikes can be bought or built from components at a much higher cost. There isn’t a big difference between average and custom bikes – a good rider on an average cost BMX will beat an average rider on a no expense spared custom bike! Doing well in races is more determined by fitness level, technical skills, race tactics and the desire to win!
When browsing bikes to buy, remember that it should a 'BMX Race' bike as opposed to a 'BMX bike'. The latter is not designed for racing! Most on-line retailers 'categorise' to help differentiate between the two. Shop around as prices for the same model can vary widely between retailers. You can usually find a 'size guide' online for each bike brand's offerings. If in doubt - ask someone knowledgeable.
Local Shops:
On Line retailers:
On line trading sites (joining these groups may be subject to vetting - restricted to bona fide BMX racers to avoid scammers posting adverts):
Used:
From to time members of one of the local clubs may have bikes or equipment to sell. Manx BMX Racing is happy to list used bikes for sale locally.
Popular (not exhaustative list) race bikes are made by:
www.chasebicycles.com
www.gtbicycles.com
www.harobikes.com
www.meybobikes.com