Books - What are you reading?

My seven year old son wants a "chapter book" about cycling. He sees me reading a lot and wants something of his own. Trouble is most of the stuff I have will be pretty boring for him, or be a bit too sweary.
Anyone come across anything kid friendly?

Alastair Humphreys wrote a kids version of his book about cycling round the world, not sure what age group it's for though. The Boy Who Biked the World