Hi, I'm in the same boat as the OP. Looking for a BMX bike for my 8 year old, he's 55" tall. When he rides his older brothers 20" it seems too big for him in 2 areas specifically. The bars seem really massive and spread out and the cranks (170mm) are really too long for his legs. I called a bike shop and explained the situation, they had 2 suggestions. The Haro Z20 and the Redline Raid. Both have compact frames and smaller bars with shorter cranks but still use 20" wheels. This made complete sense to me. I would suggest looking for something with shorter cranks and smaller bars.