Originally Posted by therealcarrie

I have a low-end hybrid bike, a 21 speed Giant Cypress from around 2000.

I use it for commuting on a daily basis, usually short distances of a few miles. I had it for many years and in prior years I just used it for leisurely riding. I never used it for commuting before this February.

I have become much more competitive in my biking this year and now find I am almost always in the hardest gear. I stand up to pedal most of the time, especially going up hills. Early in the year, it wasn't shifting well and I paid for a tune up. A month later it's shifting got worse and then the shifting didn't work at all.

Please be more specific: in what way did the shifting get worse, and when it stopped working all together, how did that manifest itself?

The bike shop said the back shifter
shifter, or derailer?
was broken and apparently this occurred due to the sharp angle of the chain between the front and back with me always in the hardest gear. I got the shifter replaced and it worked okay for a few weeks, and now I find again that the shifting is getting worse. When I put a lot of pressure on the pedals, the bike skips down a gear
to an easier gear? or harder one? then does it stay there once you let off on the pressure, or does the chain return to its original cog?
- this happens almost continuously and occurs more frequently when in the harder gears. I hate the constant "giving way" feeling.

I have a few questions -

1) Should I just get it tuned up again? It seems like it shouldn't need a tune up so soon, and this problem seems to just keep coming back. Is there some reason why my bike would keep getting untuned so quickly? I am beginning to think that this bike is just too low-end in it's components to deal with the kind of use I am giving it.

2) Should I invest in better components? It has some sort of shimano shifter on it now, but I don't know if it is a good one.

3) Should I just get a new bike at this point? It would be nice to have something that more matched my abilities, but I am hesitant to do this because I am living in a neighborhood with bike theft, and I am afraid of having anything too nice.

Appreciate the advice.