Junior Development Gears

http://www.usacycling.org/rulebooks/2004_uscf_rulebook.pdf

Go here and download the rule book. Basically it says juniors can have a maximum development of 7.93 meters which is a 52x14 or 45x12 with 700c wheels but for anything less than Nationals you can just block out gears bigger than that.

Good luck in your racing!

Thanks alot. What if I do go to Nationals? Then how do I make my bike legal. There in my home town this year so it's very likely I'll attend.

Then you just get a cassette/crank/wheel combo that gives you a biggest gear less than that. When you show up for a junior race, the official puts your bike in its biggest gear and pedals one revolution of the cranks along a measured distance and if it's more than 7.93 meters you can't race.

My wheels roll 2.11m per revolution (I know because I enter it in my Flight Deck computer) and for each crank revolution you get (nFront / nRear) wheel revolutions, so a 53x12 gives a roll out (development) of (53/12)*2.11meters = 8.60 meters. To race juniors with my wheels and tires, I'd need 53x15, 52*14, 50*14, 48*13, etc. Any bike shop that deals with racers should be able to help you.

Mate, they are massive gears for a 15 year old. In Australia the biggest we can run for U/17 is 40-13 with 700CC wheels. Further advice: Go just over your gear limit, and before your rollout let a little air out of your tires and ride around on cold wet grass. Hehe.

Quoted post said:

Originally posted by Roadie_scum
Mate, they are massive gears for a 15 year old. In Australia the biggest we can run for U/17 is 40-13 with 700CC wheels. Further advice: Go just over your gear limit, and before your rollout let a little air out of your tires and ride around on cold wet grass. Hehe.

NSW, Australia junior gear restrictions for both road and track -

Under 11 - 5.00 metres
Under 13 - 5.50 metres
Under 15 - 6.00 metres
Under 17 - 6.50 metres
Under 19 - 7.93 metres

The US uses 7.93 metres for all groups under 19 for road. On the track they have reducing restrictions for age categories below under 19.

The US must feed their young road juniors more than fast foods if they can handle 7.93 metre development gears 🙂