View Single Post
Old 06-21-13, 04:43 PM
  #19  
longbeachgary
Senior Member
 
longbeachgary's Avatar
 
Join Date: Sep 2008
Location: Beautiful Long Beach California
Posts: 3,603

Bikes: Eddy Merckx San Remo 76, Eddy Merckx San Remo 76 - Black Silver and Red, Eddy Merckx Sallanches 64 (2); Eddy Merckx MXL;

Mentioned: 1 Post(s)
Tagged: 0 Thread(s)
Quoted: 143 Post(s)
Likes: 0
Liked 2 Times in 2 Posts
Originally Posted by caloso
He's nowhere near to spinning out junior gears.
I didn't say he was.

Originally Posted by hambertloot
Why? What are junior ages? I thought 17 was a junior age? I haven't looked into it, well, a while ago i did

caloso: correct, I have for my biggest a 53x12 .. I don't wanna get a new cassette etc so next year I am just going to upgrade to a new bike
Originally Posted by hambertloot
i dont get it though. yeah, USA Cycling wants juniors to "save their knees" but honestly, who rides flats in the 52x12? I only use the 52 and three smallest cogs when descending a hill and I never mash going downhill, i spin to 100rpm then shift down which I am sure many people do the same? idk,

im usually in the middle of my cogs in the back on the 52 front or doing something on my 42 front
Junior Gear Restrictions: Is your race bike legal?

Junior gearing can be a surprise to young athletes trying the sport of cycling for the first time. The young athlete attending his first USA Cycling-sanctioned event may be shocked to find his bicycle considered illegal. Parents may also wonder why this is so, especially when they have paid a lot of money for a bicycle they were told was race-ready. The main purpose of junior gear restrictions is to help the young rider develop a good pedal cadence and to avoid injury. Junior gear restrictions also level the playing field for developing juniors who may be at a disadvantage against rivals who possess physical advantages such as height and power.The test to see if a race bike is legal or not is called the "rollout method" or simply "junior rollout," which is the distance a bike travels backward in a straight line through one full pedal revolution when the bicycle is in its largest gear. The junior gear restriction for road events is 26 feet (7.93 meters).
To calculate how far a bike will travel relative to its gears, USAC suggests gear ratios with respect to race age and discipline. The gear limit for a rider is determined by the age of the rider and the discipline, and applies in all events in that discipline.
There is no restriction for cyclo-cross. For road and track the limits are:
Road
17-18: 7.93 meters (26’)(52x14)
15-16: “
13-14: “
10-12: “
Track
17-18: Unrestricted
15-16: 6.78 meters (22'3")(48x15)
13-14: 6.36 meters (20'10.5")(48x16)
10-12: 6.00 meters (19’8”)(48x17)
Note that the gear ratios listed are merely suggestions – the distance rolled out is the governing standard.
Race officials will usually provide a courtesy gear check prior to the start of a junior race but ultimately it is the gear check immediately after the junior race that determines whether a junior's bicycle is legal or not.
The official checks a junior's bicycle's gears not by counting the number of teeth on the largest chain ring and smallest cassette cog, but by rolling the bicycle backward in a straight line for 26 feet. If the bicycle travels 26 feet or less when rolled backward one full pedal revolution, the bicycle is legal. If the bicycle rolls past 26 feet, the rider is disqualified for not complying with the junior gear restriction.
Ultimately it is the athlete's responsibility to make sure his bicycle is compliant with junior gear restrictions. The purpose of the courtesy check is to offer the junior the opportunity to block their gears prior to competing in his event. Note that blocked gearing is not permitted at USAC National Championship and UCI events. Depending upon the rear derailleur's stop limits and rear cassette cog combination, there is no guarantee that a bicycle with blocked gearing can be made legal, since it all comes down to the distance traveled in the largest accessible gear. Blocking means adjusting the rear derailleur's high stop limit screw to prevent the chain from going to a small rear cassette cog.
It is also important to note that not all cycling tires have the same diameter, which can give a bicycle a rollout distance different than the distance provided by the gear recommendation.
Junior riders need to roll out their bicycles on their own prior to attending a USAC-sanctioned event to determine whether they will be compliant with the rules.
longbeachgary is offline