Derailleur problems, can i fix them myself?

Question

basicaly, my front gears by my pedals has three sets of gears, and the derailleur only shifts to the 2 bigger ones.

and for the back, i have 6 gears. when i'm in first, its fine, then i shift to 2nd, and it shifts fine, but then it automaticaly shifts to third. and the same happens when i put the selector to 3rd gear, it shifts to 4th, then 5th by itself. and when i go to 4th, it shifts to 6th. can i fix this myself? i have some skill with tools, but not about how a bike derailleur works, but i can learn. do you think i can fix it myself? if so, how can i?

thanks

Answer 1

This is a great opportunity to learn.  

Rear derailleur: In all likelihood your shift cables require adjustment, a common cause of gear skipping.  It may be necessary to replace the cables and this is not a complicated procedure.  Try this link for info - http://www.jimlangley.net/wrench/rrderad...

The front derailleur could be affected by a cable that is too tight/loose (depending on the type of derailleur) or an improperly set low limit s***w.  Try this link for info - http://www.jimlangley.net/wrench/ftderad...

Bicycles are rather simple machines and you will get a great deal of pleasure from completing these fixes yourself.

Answer 2

This is the problem with index shifting. It used to be easier to adjust the deraileur before index shifters were invented.

Answer 3

i would take it to a bike shop

Answer 4

take it straight to the bike shop.  ask them if you can watch the adjustment, so in the future you will have a better idea of how the limit screws work. as well as cable tension.