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Discussion Starter #1
My son's bike currently has 53/39:28/13 gearing and is hard for him on climbs, I ordered a compact 50/34 crankset in oder to ease the gearing up front.

Now the question is, should I change the cassette with a different gear combination? or should I keep the current one. I have 2 spare road cassettes that could use if needed, 23:13 and 26:12.
 

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DiRt DeViL said:
My son's bike currently has 53/39:28/13 gearing and is hard for him on climbs, I ordered a compact 50/34 crankset in oder to ease the gearing up front.

Now the question is, should I change the cassette with a different gear combination? or should I keep the current one. I have 2 spare road cassettes that could use if needed, 23:13 and 26:12.

You should read some of C40’s posts on gearing.

The 39-28 combo your son had would be only slightly larger than a 34-25 combo. This means that your son would benefit from a cassette with a 12-26 spread, thus providing smaller jumps and a nice and easy 34-26 combo. You might have to remove a link or two from the chain.

Hope this helps,

Des
 

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equivalent gears...

Most riders would find a 50/13 top gear to be too small, since it's about the same as 53/14. The formula to calculate "equivalent gears" is simple. In this case, it's 13/50 x 53 = 13.78, which says that the 50/13 is very close to a 53/14. The 34/28 would produce a low gear equivalent to a 39/32 which is a significant improvment.

The 12-26 cassette would probably be a better choice for top gear, since it's a bit higher than a 53/13. At the low end, a 34/26 gear is the same as about the same as a 39/30, since 26/34 x 39 = 29.8. Unfortunately, that's only about a 6% lower gear and won't help tremendously on the hills. An 8-11% reduction would be a typical "one-cog shift".

I hate to say it, but a compact crank can be a pretty expensive way to gain just one cog's worth of low end. You don't mention if this an 8 or 9 speed cassette. A 12-26 cassette isn't very common. Most 9 speed cassettes are either 12-25 or 12-27.
 

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Hoopy Frood
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C-40 said:
I hate to say it, but a compact crank can be a pretty expensive way to gain just one cog's worth of low end. You don't mention if this an 8 or 9 speed cassette. A 12-26 cassette isn't very common. Most 9 speed cassettes are either 12-25 or 12-27.
He's probably using a SRAM road cassette. They are available in 11-21, 11-23, 12-23, and 12-26.
 

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Discussion Starter #5
It's a SRAM 8 speed cassete with a Tiara rear mech.

I thought that by reducing the ring size we should get "easier" gear combinations but if I follow you correctly I'm just wasting money.

I just want the gearing to be easier for my kid.
 

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Squirrel Hunter
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Juniors and Gears

DiRt DeViL said:
My son's bike currently has 53/39:28/13 gearing...
Well since your son recently got into racing you should also consider becoming familiar with the rules regarding junior gear restrictions before buying more stuff. Also keep in mind as you get all the advice here that everyone assumes he is using 700c wheels. Numbers will vary if he is using smaller wheels.

If you are getting the compact to have more low end then stick with the 13-28 cassette. As C-40 noted you do not gain much low end with the 12-26. The 13-23 provides even less low end than your current setup.

Kids develop quickly and perhaps if he only struggles a little on hills and your area terrain permits you should just choose different (flatter) routes until he becomes more adept at riding. Then in a couple of months he will be stronger and attacking those hills with his current gearing. It is very hard to convince kids but you cannot buy speed and power at the local bike shop it comes from riding and training. Your job is to keep the riding and training fun. It is equally hard to convince Masters that you cannot buy speed since most have more money to buy speed than time to train.
 

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Discussion Starter #7
Good point, were I can research the Junior gear restrictions?

He'll probably need a new bike for next year so we can start to find stuff out now.
 

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Squirrel Hunter
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Rulebooks

DiRt DeViL said:
Good point, were I can research the Junior gear restrictions?

He'll probably need a new bike for next year so we can start to find stuff out now.
Will he race under USA Cycling rules, UCI, other?

Online rulebooks:
http://www.usacycling.org/news/user/story.php?id=369

The rulebook is a bit confusing and without someone to interpret it for you I am not sure how much it will help. Post his current bike specs here as far as gearing (big chainring size) and wheel size. If no one provides Junior gearing details I will pop back in in a couple of days and give you some more information. I wont have time before Thursday to get online and answer.
 

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Discussion Starter #9
Will be UCI, are the rules different from USA Cycling?
 

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DiRt DeViL said:
Will be UCI, are the rules different from USA Cycling?
On the road the rules are the same, I can't verify that for the track however.

As per the UCI's road rules: 2.2.023 (N) For juniors men and juniors women, the maximum gear ratio authorised is that which gives a distance covered per pedal revolution of 7.93 metres.

That works out to roughly a 52 front with a 14 rear on 700x25 tires. A 50/13 on 700x25's might be a little too big.(8.1 meters if memory serves). There's a quicky calculator located here:
http://www.sheldonbrown.com/gears/

UCI rulebooks:
http://www.uci.ch/modello.asp?1stLevelID=H&level1=0&level2=0&idnews=2676

UCI road specific section:
http://www.uci.ch/imgArchive/Rules/2road-E.pdf

Hope that helps.
 

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naranjito
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I would think that if 39/28 is not low enough for him on the hills then there´s no way he´s going to be able to push the largest ratio on a junior block (52/14 usually as someone said), let alone a 52/12 or the 53/13 that he has now...
I´m not a coach nor do i pretend to be an expert, but, depending on his age and physical maturity, if he can´t get over the hills on the gears he´s got (which really are pretty low - depending on the hills!), then I would spend a few months on the flat with low hills built in to build up some cycling muscle before going to harder stuff. Avoid burning him out and ruining his knees by letting him use whatever gears he has and pushing too hard, or by trying to ride mountains or distances that are beyond his ability at this stage. One of the most important lessons to learn as a junior is how to spin - after that the ability to turn larger gears will come naturally.

foz
 

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Discussion Starter #12
He's not at Junior age or level yet but keep the info coming. It will be very helpfull when he joins the Junior ranks.

BTW, he's running a Trek KDR1000 which has 24" wheels. Sorry for not mentioning that earlier.
 

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Discussion Starter #13
Another racing related question, does USA Cycling allow any US Citizen to get a license or has to be living in the continental USA.

The kid already has an UCI license but I was told that I should get one from USA Cycling if he plans to continue racing so he can build a portfolio/resume in order to request scholarships, is that true?
 

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DiRt DeViL said:
Another racing related question, does USA Cycling allow any US Citizen to get a license or has to be living in the continental USA.

The kid already has an UCI license but I was told that I should get one from USA Cycling if he plans to continue racing so he can build a portfolio/resume in order to request scholarships, is that true?
I really don't know the answer to that one. You should probably check directly with the Puerto Rican federation, and USA cycling . I know there are riders from outside the continental U.S. that ride with U.S licenses, but I'm not familiar with the particulars.
 

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Discussion Starter #15
mh3 said:
I really don't know the answer to that one. You should probably check directly with the Puerto Rican federation, and USA cycling . I know there are riders from outside the continental U.S. that ride with U.S licenses, but I'm not familiar with the particulars.
He got the UCI license thru the PR Cycling Federation but we were told that a parent signed his kid (Junior) on the US and rides the local series as a foreigner/visitor because he's already documenting the kid results thinking about scholarship.
 
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