So when does KJ01 - 7 soon to be 8 need to worry about what type is required?
I know with CX you can use an MTB, but with MTB you cant run a CX in youth/jnr adult.
So until what age can he turn up on whatever he likes?
Not sure on the rules, but in regional xc the kids races have been getting progressively harder/ more technical to try and reduce the jump to a full adult lap later. In the Southerns we have had some excellent BC coaching on race day to go along with this. On this basis, I would say that a cx bike will become increasingly difficult to manage on these courses and rightly so, it's mtb xc.
I [i][b]think[/b][/i] that for MTB XC it is commisaires discretion, the bike has to be suitable to complete the course.
Fwiw - U7, most kids bikes are the do-it-all rigid forked type anyway. 8 and over and most are on hardtails with a suspension fork.
I'm a CX commissaire - the primary consideration is whether the bike is appropriate and safe for the conditions rather than whether it fulfils the technical criteria - being able to operate the brake levers for example. Some MTB events usually specify a minimum tyre width of 1.5" / 38mm but I've never seen anyone enforce the regs
My kid is 8 and has just outgrown his current bike, so I just got him a secondhand 24'' wheel road bike to do some cross races on. Without thinking it through particularly, as riding it it's apparent he can't operate the drop bar brakes very effectively.
However, I reckon fitting some top bar levers into the brake line will sort this out and he'll be good to go.