Can I just replace my shifters?

Question

I recently bought a 1993 Schwinn Crisscross (specs here: http://www.bikepedia.com/QuickBike/BikeSpecs.aspx?Year=1993&Brand=Schwinn&Model=Crisscross&Type=bike)

The shifter for the rear dérailleur is a bit wonky. It won't shift all the way to the largest gear, sometimes it clicks into place but doesn't actually shift to the next gear, and sometimes it is real jerky when shifting. Adjustment of the dérailleur doesn't seem to help. I've never replaced a shifter before, so could I put just any shifter designed for seven rear gears on this bike? Is this a reasonably straightforward operation, or should I pay the bike shop to do it?

Answer 1

It sounds to me like it might be time for a new cable and housing.   All of the things Mirage mentioned are things you should also check (or have a bike shop check), but it really sounds like it could be a sluggish or frayed cable causing that.  

To answer your question, yes, you can put any 7-spd shifter on there and it'll work.  You'll need to know how to adjust the cables, set up the derailleur properly from scratch, and fiddle with the grips on your handlebars.  Try all of these other things before you replace the shifter...most of them last seemingly forever.  If you narrow it down to a problem with the shifter, see if you can open it up and lube the mechanisms...often that's all you need to do to get it working again unless something is actually broken or worn out.

For great instructions and photos, check out the "repair help" section at http://www.parktool.com .  It'll show you how things are put together....even if you don't want to do the work yourself, at least you'll understand what the bike shop is doing and can understand the shop mechanic's language clearly.

Answer 2

I assume that you also checked the cable tension BEFORE adjusting the derailleur limit screws, right?

My guess is that your shifter and derailleur is OK but your rear derailleur hanger is bent. This needs a special tool to correct.

Not clicking into gear sounds like the limit screws ARE NOT correct. Try turning the "L" s***w about 1/4 turn counterclockwise after you make certain cable tension is correct, and try again. Indexing on the shifter is not something that changes and not something that can get wonked up.

I suggest having the hanger and dropout alignment checked if the L limit s***w adjustment and cable adjustment doesn't improve things.