Junior Gearing



crazyb1

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Feb 29, 2012
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Hello, I'm new to the forums and this coming summer I will be new to competitive cycling, I'm 17 and I would need to know what kind of gearing would be allowed in USAC sanctioned races. Currently I have a 50-34 front, and a 12-25 in the rear, would this work, or should i buy a different cassette or chain ring?
 

An old Guy

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Feb 12, 2011
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http://www.usacycling.org/forms/rules/JUNIOR_GEAR_ADJUSTMENTS.pdf

I think a 50/14 high gear would work out.

http://www.excelsports.com/main.asp?page=8&description=Ultegra+CS-6600B+10+Speed+Cassette&vendorCode=SHIM&major=1&minor=10

While you can lock out the higher gears on your existing cassette, buying a new cassette gives you a larger variety of gears.
 

swampy1970

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Feb 3, 2008
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http://www.usacycling.org/forms/rules/JUNIOR_GEAR_ADJUSTMENTS.pdf

The gearing you have will NOT work.

Note: the above pdf is not taken from the current official rule book and references the 2006 rules. The current rules MAY be different. I posted the above as it has several different gear combinations that are useful and if the gear requirements have changed you can play around with the gearing accordingly. The gears are checked via a "roll out" and this is a combination for gear and tire size.

Personally, using your current gearing I'd buy a 52 tooth, 110bcd chainring and use the outer limit screw to prevent your rear gears from being able to change in the 12 and 13 sprocket. If you plan on running the same tires all year - say a 700x23, you'll be fine and it'll also give you some wiggle room to use a 700x25 if you happen to do an event where the surface is very bumpy. TA do make a 45 tooth outer chainring - the only place to buy those from in the US is Peter White Cycles - but you'll be limited to a 23c rear tire. Some tires run wider (and taller) than others and may prevent you from passing the gear check at races with the 45x12 combo.

The first thing you should do is get a current copy of the rule book and understand all the rules for your class. I know I probably sound like your parents right now but if you screw up and flaunt the rules, even if you don't mean too, you'll likely not realize this until you turn upto the race, which is just about the worst time to find out. Sure, there's NEARLY always someone around that can help you rectify the situation but then again with the usual myriad of other classes there might not be.

Have fun and good luck.
 

crazyb1

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Feb 29, 2012
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Aren't there disadvantages to blocking out gears? Also if i do decide to race with blocked gears, should I train from now on with that configuration? Oh don't worry about sounding like my parents, they really don't care much about cycling, and I've been supporting my own cycling habit from a part-time job so being cost effective is also important. :p
 

An old Guy

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Feb 12, 2011
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If you block out your gears you will have 2 less gears to use. And there will be gaps.

14, 15, 16, 17, 18, 19, 20, 21, 23, 25

14, 15, 16, 17, 19, 21, 23, 25

I don't think it will matter to you. But you can set the adjustment screws and ride that way now. See how it works.
 

danfoz

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Apr 12, 2011
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Originally Posted by crazyb1 .

Also if i do decide to race with blocked gears, should I train from now on with that configuration?
Personally I would train in the same config I race in (and do). That way there's no surprises and you know the equipment.
 

alfeng

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Jul 23, 2005
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Originally Posted by crazyb1 .

... this coming summer I will be new to competitive cycling, I'm 17 and I would need to know what kind of gearing would be allowed in USAC sanctioned races. Currently I have a 50-34 front, and a 12-25 in the rear, would this work, or should i buy a different cassette or chain ring?
FWIW. Because different tires may result in a different circumference, UNLESS you are absolutely sure of the ROLL OUT which a particular combination will result in, I think you are probably better off choosing a 44t outer chainring rather than a 45t outer chainring to use with your 12-25 cassette ...

It would be a pity to be turned away before the start of an event if the bike's roll out were an inch-or-two too long.
 

crazyb1

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Feb 29, 2012
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If I change the front to a 44t do I still have to block out the 12, and 13 on the rear still? I also heard that some roll out measurements be in accurate up to about 1 1/2 inches.
Originally Posted by alfeng .



FWIW. Because different tires may result in a different circumference, UNLESS you are absolutely sure of the ROLL OUT which a particular combination will result in, I think you are probably better off choosing a 44t outer chainring rather than a 45t outer chainring to use with your 12-25 cassette ...

It would be a pity to be turned away before the start of an event if the bike's roll out were an inch-or-two too long.