# Cassette / Crankset #'s



## FINEMNT (Sep 14, 2009)

Seems that I'm asking a lot of questions today, sorry. I see that there are different number of teeth on cassettes and cranksets. I'm new to this, so what do these numbers mean when higher or lower? I'm assuming this matters on the type of riding someone does, am I correct? I live in south Tx, all flat roads here. So what would be the best option here? I'm getting the neuvation F100 in x-mas, and I know you can swap out some of these things. Thanx for any info.


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## JCavilia (Sep 12, 2005)

*some stuff for you to read*

http://www.sheldonbrown.com/gears.html
http://www.sheldonbrown.com/gearing/index.html

As for your gear choices on your new bike, since you live in a flat place it's easy to cut to the bottom line: it doesn't matter much. Whatever gears come stock on the bike will work for you. Wind conditions will be the only thing that really forces you to shift, and any stock setup will give you plenty of gear range.


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## MerlinAma (Oct 11, 2005)

You can get endless discussion about gearing so I'll not suggest any specifics.

That being said, here is what I think you need to consider.

1) Your lowest gear should allow you to climb anything you routinely ride. I get one answer for where I live, and another answer when I go to mountains. That means two different cassettes, as I really want #2 below to the extent possible.

2) Gear spacing, best case, should be reasonably even throughout your gear range. For example if you start in your low gear, the next gear would be 10% higher and the next gear 10% higher, etc. That's why most cassettes only have 1 tooth difference on the high end but several teeth difference on the low end. It's to get the same % change. And you generally want the smallest % change possible so as to keep your cadence within a narrower range.

3) Minimize cross over gear changes. Best case you could start on your small chainring, shift through most of the cassette, shift once to the big chainring, find a similar gear on the rear cassette, and continue without shifting the front again. If you have to shift both front and rear derailleur to achieve #2 above, it is a real pain.

4) Although not all that common, you want a gear high enough to keep up with your competition, be that a friend or whatever. I never had an 11 tooth cog until friends riding a tandem ran off and left me on a long downhill. That made me reconsider.


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## John Nelson (Mar 10, 2006)

FINEMNT said:


> Seems that I'm asking a lot of questions today, sorry. I see that there are different number of teeth on cassettes and cranksets. I'm new to this, so what do these numbers mean when higher or lower? I'm assuming this matters on the type of riding someone does, am I correct? I live in south Tx, all flat roads here. So what would be the best option here? I'm getting the neuvation F100 in x-mas, and I know you can swap out some of these things. Thanx for any info.


Larger number of teeth on the chainrings (the gears up front) mean it will be harder to pedal and you will go faster.

Larger number of teeth on the cogs (the gears in back) mean it will be easier to pedal and you will go slower.

The highest gear (faster/harder) is determined by the ratio of the teeth on the largest chainring to the smallest cog.

The lowest gear (slower/easier) is determined by the ratio of the teeth on the smallest chainring to the largest cog.

So suppose you have a large chainring with 52 teeth and a small cog with 11 teeth. The ratio is 52/11 or 4.73. That means that the rear wheel goes around 4.73 times for every revolution you pedal the crank.

Now suppose you have a small chainring of 39 and a large cog of 25. The ratio is 39/25 or 1.56. That means the rear wheel goes around 1.56 times for every revolution you pedal the crank.

Given the above sample numbers, your range of gears is 4.73/1.56, or about 3 to 1.

Unless the swap out is free at the time of purchase, it rarely makes sense to waste your money changing anything. As others have said, whatever comes with the bike will work fine for you. Wear out what you have before buying something else. It's almost always a myth that you can buy your way to better biking. Just ride.


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## FINEMNT (Sep 14, 2009)

John Nelson said:


> Larger number of teeth on the chainrings (the gears up front) mean it will be harder to pedal and you will go faster.
> 
> Larger number of teeth on the cogs (the gears in back) mean it will be easier to pedal and you will go slower.
> 
> ...


Extremely informative! Thanx John! The swaps are for free. I just wanted to make sure I was getting the right set up, if it even mattered. Thank you all.


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