Haven't had time to read through all this thread, but congrats to all who have got their kids on to half-decent bikes that the kids will enjoy riding, and who will hopefully continue to ride and upgrade to bigger bikes as they grow
An observation on ByK bikes and the local bike industry. ByK gave Australians a long belated decent choice of bikes for kids of all ages a few years ago, and it seems some other local bike companies followed suit with some half-reasonably designed and specced kids bikes. Check out the Radius (Apollo) Neo range
No affiliation, but I've usually found Apollo Kids bikes reasonably well specced for the price - It's amazing how some more expensive 'boutique brand' kids bikes skimp on quality somewhere (usually wheels), ie single wall rims, steel hubs, cheap spokes....
Having said that, I'll be seriously looking at a ByK E-550 MTB for my son when he turns ten in about eight months. Since eight, he has been riding a heavily modified (forks, headset, bars, stem, post, brakes, levers, grips, tyres, bell crank, chain ring guard, gear ratio, decals.....[!!!] ) Fourty 3-speed
, but in my eyes, this bike in standard form has lots of shortcomings (ie; see my mods, heavy frame).....
< ....but he don't seem to mind too much!
PS: Whilst some junior race BMX's may be light, they are designed primarily for stand-up sprinting over jumps etc, and they usually have a relatively high bottom bracket height, making it difficult to get a low enough seat height to touch the ground without the kids knees being up around their chin! That image back on page 9 is a perfect example of a race BMX being an inappropriate fit for general riding!!!
And also take into consideration of all the different tyre sizes on kids bikes, and the availability of tyres and tubes ie, 18 x 1.5 (355), 20 x 1.5 (406), 20 x 1 3/8" (451), 24 x 1 (520), 24 x 1 3/8" (540), 26 x 1.9 (559), 650C (571)..... - these are most of the sizes I know of around on 'juvenile' bikes, and some are near impossible to get tyres and tubes for! ByK are good at supplying relevant tyres and tubes for their models, but I know some big brands in Australia that can't supply or know of supplies in Australia for their own models - the Avanti Blade Junior is a nice bike, but try and source 24 x 1 (520) tyres for it !!!
I searched high and low to find 24 x 1 3/8 (540) knobbies for the Fourty , and they weren't cheap