How to use front derailleur on road bike?

I always use rear derailleur. Is front derailleur for going very very fast? I only use the small cog on the front.

Using the smallest front cog (called a chain ring) gives you a lot of power but not much speed. You will go faster on flat ground if you use the middle chain ring. You'll go even faster if you use the outer ring (assuming you have a triple) so you can pedal while going downhill.

The simplest way to use a triple is to start with the middle chain ring up front. As your terrain changes, go to bigger gears in the back for uphills and smaller gears in the back for downhills. Shift the front when you run out of back gears.

There is one other reason to shift to a different chain ring. That's when your chain crosses a lot of gears, such as the smallest ring up front with the smallest cog in the back. You will probably hear the chain rubbing the derailleur. That's called cross chaining. Shift to the middle ring and to a larger gear in back to make the rubbing noise go away.

HTH

1st gear on front is really easy. 2nd gear on front is normal riding. 3rd gear on front is for going fast. You should try using them.

Bicycles are very primitive machines (that's why I like 'em) The front derailleur essentially forces the chain off of one chainring onto another.

The larger chanring is better if you're confident you can pedal harder and faster while on the flat or going downhill.

Just try it out, it can't hurt to try*





*not a guarantee :P

Bicycles aren't rocket science. You have the bike, don't be afraid to simple shift your front derailleur. It won't bite you and you'll learn something on your own. Your results of this experiment will be self evident...

The front derailleur (FD) performs the same function as the rear der. It allows you to move your chain onto a different size gear. The FD on a road bike usually allows you to choose between 2 or 3 chainrings (3 is referred to as a 'triple' and 2 a 'double'; the double is most common for road bikes). If you usually ride in the smallest chainring up front, switching to the larger chainring will give you larger gear-inches; in essence, one turn of the crank, will translate to covering greater ground at the wheel. If you were to turn the crank at the same rate on the large chainwheel as you did on the small chainwheel, you will go A LOT faster. However, it takes a lot more effort to turn this bigger gear. Therefore, the large chainwheel is best used; when you want to go faster, like going downhill or in a sprint. You can run the large chainwheel in front witht he larger cogs in back to make it 'easier'. However, it is recommended that this 'cross-chaining' be avoided because it places stress on the chain and wears parts quicker. It's best to down-shift the FD onto the smaller chainring if you want to use the larger (easier) sprockets in the rear.
One other note; pushing big gears and slow cadence is hard on your knees - spinning a smaller gear faster is a much better approach.
Don't be afraid of the FD, experiment with it and you'll find it very useful, just like the RD.

Think of the chainrings up front as different gear ranges. If you have 3 chainrings, they are a normal range with the middle ring, a low range with the small ring, and an overdrive with the big chainring. If you only have 2 chainrings, you don't have the low range, but you still have normal and overdrive.

How to use them:
Do most of your riding in the middle ring. That's 'normal' range.

If you are in the highest gear in your normal range and your feet are going too fast, then shift to overdrive for more speed at a given cadence. You lose torque, so climbing hills will be harder in overdrive.

If you are on a long or steep hill and the lowest gear in your 'normal' range is still too hard, then shift to the low range. for more torque at the expense of speed.

If you change to a different gear range, you can still shift the rear gears to find a comfortable one. Avoid 'cross-chaining,' which is the big/big or small/small gear combinations. Those are hard on the chain. When the need for low range or overdrive is past, you can shift back to 'normal.'