Gear question?

Question

I have only had my road bike a little while now so forgive me if I sound clueless.

Well, I am use to shifting on the right side (the gears in back) and now I am trying to understand the gears in front. I have 3 different options. I usually keep it in the very middle. But when I am riding on trails that are flat as a pancake, do I get more power when I shift my front gear from the middle, to the higher one? Does that make sense? Told you I was clueless but I am learning. Thank you so much for your answers.

Answer 1

You started out good- learn your rear gears before throwing the front ones in!

You're used to the bigger cogs in back being "easier" to pedal, while the smaller ones are "harder", right?

Well, the rear will work the same way, but the front ones will shift that range up or down depending on which chainring (front gear) you are in.

Do what you did with the rear gears, only in reverse.  Shift the rear into a cog somewhere in the middle, and on flat ground shift the front to a different chainring and see what effect it has.

Generally, the big ring will allow you to go faster, but isn't easy when climbing.  The small ring will be great for climbing steeper hills, but you won't be able to go as fast without spinning your legs stupid-quick.  Practice and have fun!

Answer 2

The big ring at the front and the small ring at the back gives you the highest gear ratio, that means for each revolutiuon of the pedals, the bike will travel the farthest and you will need more strength in your legs to propel you along, so this gear tends to get used downhill of flat only.

The small ring at the front and the big ring at the back is the lowest ratio, used for uphill only, or starting from standstill.

Then you have all the gears in between to select to suit the conditions, try riding somewhere flat and using different combinations to get the feel of the bike and how to change gear.

Couple of things to remember, when coming to a stop, drop the chain to the smallest ring at the front, makes it easier to pull away, and, never ride with the chain on the big ring at the front and the big ring at the back, this doesn,t do the gear train any good.

Answer 3

To get a good idea of the way the gears work to keep in your head is,

1) The bigger in front you go the faster and harder, the smaller you go in front, slower but all so easier.

2) In the rear, bigger is slower but easier, smaller in harder but faster.

Answer 4

The big gear in the front will give you lots of speed but not much power, good for going fast on the flats and very fast down hills. The little gear in the front will give you lots of power but not much speed, good for going up hills.

You're on the right track. A point to remember is that your drivetrain should be silent. If you are in the big gear up front (called chain rings) and a big gear in the back (called cogs), then the chain is at a pretty big angle to the bike's line. You will probably hear the chain rubbing the derailleur. This is called "cross chaining." In that case, shift to the middle chain ring and a smaller cog to compensate. Your drivetrain will be quiet and pedaling more efficient.

HTH

Answer 5

You are right to stick mainly to the middle ring in front. The majority of the time you will find those gears are fine.

Simplistically, you could think of the smaller ring at the front as being for steep hills and the larger ring for when you want to power down hills or have a tailwind. But in reality it's a bit more complicated.

First, bikes differ in how the gears relate. Two 27 gear bikes might be quite different simply because the number of teeth on the gears are different. For example two road bikes may have 9 speed rear cogs with 13 to 30 teeth and 11 to 19 teeth and the front rings may also be different, meaning that actual gearing is quite different. You will need to get familiar with how the gears on your specific bike relate (See a bit later for how).

Second, your fitness level and terrain or wind conditions will dictate you using different gears, but the basic idea is not to worry about which gear you are in, but how to adjust gears to make it possible for you to always peddle in the 70 - 100 rpm range. After all, that is what gears are for ... to allow you to maintain a comfortable effort level despite varying terrain, etc.

Third, recognize that a "27 speed" bike is unlikely to have 27 distinct gears. Several will be almost identical, and others will overlap, so there is no simple pattern to progress from one gear to another.

This all sound confusing but you can figure out how gears relate by calculating the "gear inch" value for each cog/ring combination.

The gear inch value for any gear is the ratio of the # teeth on the front ring to the # teeth on the rear cog, multiplied by 27 (wheel diameter in inches). Values between ~20 (low gears for steep hills) and ~120 (high gear for tailwinds, downhills, power sprints) are common. By plotting the specific values for each cog/ring combination (try plotting the cog values for each chainring on parallel horizontal lines lines) you can show the gears quantitatively and get a feel for how they relate. Typically you will find the gears on the rear cogs are incremented by about 6-12%, while the big, middle, small rings are about 20% apart.

The link is to a page that helps you visualize your bike's gear ratios and how you might shift efficiently.

This may be more than you wanted, but you may as well get your "feet wet". Hope it helps.