My Youngest, is four .. And he has been riding a Redline Micro with 18" Wheels for some time..
Could not find a new one anywhere.. And Shinners Redline Importers sounded almost to scarde to bring any in when i called them..( three seperate times ) , thinking dealers would not want to stock them / get stuffed up with them
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No probs I thought, just buy a new one on my card form USA .. No out of USA Sales
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Anyhow , ended up with a nice used one ... They do feel a bit strange though ! A bit long , so ive put a zero reach stem on ..
Def the way to go , and Pit Bike 12 " or 16" dose not roll as nice and will struggle pedaling up jumps etc ..