[Rogueldr]

My 8 year old son rides a 16" Cannondale. He has gotten very good on it and is now at the point of jumping curbs and stuff like that. He has learned how to do those awesome coaster brake skids that we all did as a kid and I have no problem with swapping out the rear tire when he inevitably wears it down. I mean that's what being a kid is all about right?

My problem comes with his drivetrain. He seems to have outgrown his cranks and chain ring. When he starts to pedal hard, he is spinning out his gearing which leads to a lot of slipped pedals and slammed shins (thank God for those stock plastic pedals). I tried sitting him on a 20" but he's just not there yet. I know I can swap out the parts but my question is do they even make bigger cranks and/or chain rings that would actually fit on a 16"? Any help would be much appreciated.

 

[slapheadmofo]

Yes, they do. Not sure if it's worth doing though, as he's got to be getting pretty close to outgrowing the whole bike i'd imagine. Maybe time to move up to a bigger bike? 18" was a magic size for my kid as far as BMX style bikes go. He's 11 and still would much rather ride 18"s than 20"s (even tho for MTB he's on 26" wheels.)

 

[Rogueldr]

I hear what you're saying but it's not that he is too big for the bike it's just that the gearing is too low and he's spinning it. I don't even know where to get a new chain ring or cranks that small. Any ideas? Or I guess I can just check my LBS.

 

[oren_hershco]

Maybe you can replace the rear sprocket with a smaller one?
They are very cheap, and a local bike shop should be able to install it.

 

[slapheadmofo]

Have your LBS open up the QBP, etc catalog, or just order some online.
Basic chainring and 1-piece cranks should be cheap as dirt and potentially less hassle than messing with the rear wheel.

One Piece Chrome Crank 5 1 2 " 5 5 inch 140 mm for Kids Bikes Fits 1 2" | eBay

http://www.amazon.com/SunLite-Sunli...9-7363419?ie=UTF8&refRID=12DKD2C0JY576JH5QDNK