Kids Cranks

Crank length should be considered when buying a child’s bike as this can have a major effect on cycling. The Carrera blast came spec’d with 165mm cranks which for Lewis was far too long (I use 165mm XT’s). This was noticeable as he would bob when spinning under light load. Long cranks also affect saddle height which in turn affects body position over the bars. There are a number of pages on the internet to provide the information about leg and crank length to what is suitable. I recommend reading this page on bike dynamics and this one on highpath.net

The Carrera comes with a 22/32/42 triple crank with a 12-28 7sp cassette and is fitted with a no-name cone and cup bottom bracket – 68 X 122.5 square tapper. I fitted a SRAM 12-32 cassette at the same time as the new crank to give Lewis lower gearing.