Restrictions on gear ratios - Youth

[Pure Savage]

Out of interest, what is the purpose of limiting the gear ratios? 

So you dont damage youngsters joints

[Zeffer]

I got this from the Oracle (also known as Google):

 

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.

 

Your next question is probably why not in bmx or mtb. I think firstly it is because those disciplines are newish and secondly it is highly variable compared to road and track where you might pedal at the same pace for long periods

[BeegMig]

Out of interest, what is the purpose of limiting the gear ratios? 

I was told that its supposed to prevent injury

[mtbee]

Just done the whole modification for a Junior rider. Easiest way to calculate the gearing is the following

Front big ring (teeth) / rear cassette (teeth) x by rear wheel circuference.

 

52 / 14 x 2.1m = 7.8m (for a junior)

 

if you run  a 52 / 13 gearing (52/13x2,1) = 8.4m over the limit.

a 50 / 13 also over runs (52/13x2.1) = 8.07

Running a 50 / 14 (50/14x2,1) = 7.5m well short and left behind on the ride.

[Frosty]

At Gauteng Champs last week, they did a physical roll back on the road, vs looking at the number of teeth on chainring/cassette.

 

At most races, I see the officials looking at the numbers printed/stamped on the components, and have never seen them do the actual test.

[blondeonabike]

So you dont damage youngsters joints

For sure.  But is does not help if they are racing restricted but training on bigger gears.   Ek se niks

[Zeffer]

For sure.  But is does not help if they are racing restricted but training on bigger gears.   Ek se niks

 

True. But you see them run out of steam when the pace gets hot or the diatance long. Spinning takes some doing...

[FC&P2C]

With the max 52-18, would it not be better to run a 1x11 block, run a smaller chain ring on front?

Yes it does. My 12yo running a 1 x 9 block. 35 front and 12/23 back.

Much better as the youngsters really battle changing at the front. 

I used bmx cranks and 35 blade

[gtr1]

Out of interest, what is the purpose of limiting the gear ratios?

 

At a young age the muscles and bones are still developing. So it is to stop the riders from pushing heavy gears that can do damage later on in the careers.