DS (6.2) has coordination problems and only started learning to pedal a trike/go kart last summer at just turned 5. He has had a balance bike since he was 3 and loves them but he is too big for his current one.
My friend gave me a hand me down bike last summer but it was too big for him at the time. We've tried him on it this year and we've had to put the seat as high as it will go and I think it's a bit small really. We've taken him out on it and hold the saddle whilst he's pedalling. He's happy with that and I have tried letting go a few times and he well pedal for a few seconds but as soon as he realises we have let go he panicks and puts his feet down. I'm not sure if it's because the bike is too small and his knees knock the handlebars so he feels unsafe or perhaps it's too heavy for him? His last balance bike was a heavyish normal bike with the pedals removed - but he only had to steer that, perhaps pedalling a heavyish bike is a lot harder?
We have seen a 16" balance bike, the ridgeback MX16 which is 8.8kg, the Islabike CNOC 16 which is 5.98kg and the Dawes Blowfish 16" which is 7.5kg