Bicycle derailleurs

Commuters living locally in a hilly suburbia loose a lot of peddle reeves negotiating the hilly grades. The various sprocket sizes on every bike are meant to help compensate for the loss. The trick is to use the gearing range to avoid the inevitable peddle reeve drop shifting to a gear that increases them before a tough struggle begins. The technique is very helpful in  maintain reeves both up hills and into head winds.

Any changing difficulties is caused by the inner cable that pulls the gear changers derailing the chain up and down the sprockets not being able to pull the derailleurs properly. luggage like pandio bags fouling the rear derailleur will do it. Otherwise the rest is just general maintenance.

The basics involve adjustment stop screws that are meant to stop the chain from derailing off the sprockets into spokes or the smallest sprocket fowling the chain in the frame. There is a pair screws one for the largest and one for the smallest sprockets on both derailleurs. These work fine under normal conditions. But the majority of trouble is caused by disassembly then reassembly practices re-anchoring the inner wire cables back onto the securing bolts.

Examining the inner wire in bike shops is a vindication the inner wire cable should be always be straight. Any bends or kinks the cable can't pull the derailleur properly. The procedure to fix this is as follows.

Turn you bike upside down resting on the seat and handle bars.

For the front chain wheel changer set the chain on the smallest sprocket. Depending on whether your left or right handed with one hand adjust the gear lever on the handle bars and the other turning the crank letting derailleur knock the chain dropping onto the smallest sprocket. If the derailleur stop screws are set properly the chain shouldn't miss.

If it does adjust the stop screw so that it just stops it from doing so.

Loosen the inner wire cable anchor bolt enough you can pull the inner wire out from under the nut leaving the nut attached.

Reposition the inner wire cable threading under the loose nut observing the wire is straight making sure there is no bends or kinks. Pull the inner cable tail fairly tight and tighten the nut.

If there is still a bend odds are the wire has been bent. Inner wire cables can generally be set straight and try again.

Exactly the same procedure apples to the rear gear changer. If you remove the anchoring nut completely you will find the bolt easily falls out into the rear derailleur cavity where you will find it extremely difficult if not impossible to get at it. If it get to a point where it is necessary, to help prevent the bolt from falling in, place a piece of wood lodged under the bolt head to hold bolt in place. You will be safe to remove the anchoring bolt nut completely.