[Alexia]

I need to know if I should replace the shifter or the derailer. I did have the entire bicycle recently over hauled by a local shop after it was given to me from my family.

Some information first...
1996 Diamondback WCF 4.0
Shimano Derailer - I can get the specific model later.
Grip Shift shifter

The shifter feels a bit loose. Some times if I hear the chain popping from be misaligned I can slightly move the shifter with out changing gears and that fixes it. Some times it will even pop over to nearby gears with out shifting as well.

I will post some pictures later tonight.

 

[hophead]

I need to know if I should replace the shifter or the derailer. I did have the entire bicycle recently over hauled by a local shop after it was given to me from my family.

What did your local shop do as part of the overhaul, specifically to the drivetrain?

 

[Alexia]

What did your local shop do as part of the overhaul, specifically to the drivetrain?

Tighten, adjust, grease, etcetera. I know how to do it myself, but it was faster for them to do it. It had the same issue before I hauled it in there for service. They did not make any recommendations for replacing any parts though.

 

[hophead]

It sounds like your problem may be worn drivetrain components rather than shifters & derailleurs. Check the teeth of your chainrings & cogs for wear. Also, check your chain. If you don't have a chain checking tool you can use a ruler. The pins are spaced 1/2' on center. If you measure a 12" span the first and last pins will be exactly 12" apart on center. If it's 1/8" or more over, the chain is wasted.

A new chain will look like this:

 

[Alexia]

I checked the chain. It is off by one to two millimeters. I did some additional testing and it seems the most trouble is trying to shift down past fourth into 3/2/1 with me needing to push it a little past to fully engage the shift. It has an easier time going back from first to fourth though.

I will replace the chain and will probably replace the shifter as well. I do prefer the thumb toggle shifters and not the grip shifters.