What would be a good bike for a 6 year old Boy?

We have some spiderman bike that he is riding but he is having a hard time peddling.

I wonder if the seat is to low? Are the bike with gears for a child this young


Thanks

A 6 year old can usually ride a 20" wheel coaster brake bike. However, this depends how tall he is for his age and if he can ride without training wheels. Try him on a 20" wheel bike and see if his feet can reach the ground easily. I would not suggest a multi-speed bike for a 6 year old, unless he is a really good rider , etc. A 5 or 6 speed mini-mountian bike has 2 hand brakes only and most kids of this size do not have hand sizes big enough to reach and squeeze the brake levers hard enough to stop the bike. Any other questions, go to your local bike shop. He or she is an expert.

http://www2.trekbikes.com/images/bikes/large/jet20_boysblacksilver.jpg

Trek Jet 20 singlespeed, aluminum frame, coaster brake and rear hand brake. $190.

Giant makes practically the same bike in a steel frame for $165. Will be heavier, though.
http://www.giant-bicycle.com/images/_upload_us/bikes/models/zooms/2006/Frantic_red%20copy.jpg

I wouldn't get a geared bike for a 6 yr. old. He just wants to get on and ride and do powerslides with the coaster brake. :)

Sometimes kids bikes have cranks that are too long, which means their legs are too bent at the top of the stroke to push easily on the pedals - same effect as having the seat too low.

Trek and Fisher bikes have cranks with 2 pedal threads and adjustable stems in order to allow growth.

Not exactly sure which models but most of them have it.

In the Trek to get the adjustable fit features you have to go to the geared MT60 (20"). The Jet 20 does not offer the 2 position crank fit feature.