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Bicycling in and around Sullivan County, NY

Bike Shifting
by Andrew Kalter

I have noticed that many riders have been dropping their chains or getting excessive drive train noise and thought I would give some tips.

Shifting and gear selection is an art.  The proper shift is smooth and silent. 

Rear Cassette Shifting:
When shifting to an easier gear give a mini burst of power followed by moving the shift lever.  Right before the chain locks into the next gear ease up on the power.  If done correctly you lose no speed and the shift will be silent and smooth.  The mini burst followed by the fraction of a second of no power balance out.  An incorrect shift clunks into gear with a bang.  A bad shift under power can have so much force as to make your rear wheel bend and prematurely wear your chain.  This is one of the reasons that some people break a lot of spokes.  You can literally watch the rear wheel of a bad shifter hop on each shift.  Shifting to a harder gear is very similar.  Shift and let up on the power right as the shift is being completed.

Front Shifting:
This is a more time consuming shift but basically works the same.  Since the shift takes longer you have to ease up on the power for a longer amount of time.  It is just like using the clutch on a car.  Try to plan your front chainring shifts for easy pedaling times.  For example, when you fly down a big hill going immediately into a steep climb, shift your front ring well before you lose all of your speed and are trying to hammer up the climb.

Gear selection:
There are certain gears that you have but should never be used due to chain line.  Chain line is a term that describes the angle of the chain from the front chain rings to the rear cassette cogs.  The straighter the chain line, the less wear and tear, less noise, and less resistance in the drive train.  For instance, if you are in the big chain ring and the largest cog, your chain is at a very sharp angle.  It does not want to be at this angle and will try to move to a smaller cog or fall off the large chain ring towards the small one.  If it does hang on you will typically hear grinding noises or chain rub on the front derailleur.  The same situation occurs if the chain is on the small chain ring and smallest cog although this case is not as bad because the double small combination gives the chain a lot of slack.  I typically will NEVER use the two smallest or two largest cogs with the opposite side chain rings.

Chain Dropping and Rolling Recovery:
What to do when you shift to the small chainring in the front and the chain falls off onto the bottom bracket:

Pedal very lightly as you apply continual pressure to the front shift lever (as if to shift to your big ring) until your chain climbs back onto the chainring. After this is done, release the shifter then sure you are in the gear you want.

What to do when you shift to the big chainring in the front and the chain falls off (overshifts) onto the crank arm:

Pedal very lightly as you shift to the smallest front chain ring.  Spin the cranks slowly with almost no force.  The chain will usually climb back onto the big chainring and possibly fall to the small.

What to do if the chain gets jammed and you can't pedal forward:

Try a few slow backwards pedal strokes with light resistance.  If this doesn't work you will have to stop.

The most important part of all these saves is to pedal lightly.  Applying a lot of force can cause serious damage.  One of the main causes of the chain dropping off the front rings could be a bad gear selection, as mentioned above, or improper front derailleur limit settings.


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