Getting kids (teens) into Motocross

[zooom]

i hear different bikes recommended, but what about sizes.
I've seen smaller bikes 14 in or 15in front and 17in front etc.
what is best for kids about 5' 7"

the ones I suggested are all large wheel bikes, as I figured your kids weren't small when you previously mentioned their ages.

[Curmudgeon]

i hear different bikes recommended, but what about sizes.
I've seen smaller bikes 14 in or 15in front and 17in front etc.
what is best for kids about 5' 7"

IMO the largest bike they can flat-foot as long as it's still light. (Don't ask me how I know this...  )

[rockaduc]

I would never recommend riding w/o a chest/back protector.  It only takes 1 shot to the chest from a master cylinder to convince you of their worth.  As others have said, you can get almost complete gear sets for not much $$.  Check Rocky mountain atv/mc. They have pretty good prices and selection.
Good luck!