Shifting issues
 

im having some shifting issues on my bike.
its an 07 gmc XL road bike and the problem is when i try to shift to 1st 2nd or 3rd gear, the component moves but the chain remains on the same gear. i have to manually move the chain to the correct gear every time. its equipped with shimano revo-shifts if that helps. is there something i can do? or will i need to take it in a shop?im sorry i dont have picture but will be happy to clarify anything
thanks for the help

Are you referring to the front chainrings?...or the three smallest cogs in back?...or???

the front chainrings sorry i didnt say that earlier

Here is a selection of links/videos that may help:

http://www.google.com/search?hl=en&c...q=f&oq=&aqi=g9

If you can fix this yourself by adjusting the barrel screws / limit screws / cable tension, go for it, or if there's a bike co-op near you that can help you out, that would be awesome.

This should not be too hard with a little time and some SMALL corrections. (Especially if you read this first - http://sheldonbrown.com/derailer-adjustment.html)

If you do think about bringing it to the shop, call first for a quote. If they can sort it out for $15 or so, great, but if it needs a full tune-up, you might consider selling it on craigslist and buying an older, higher quality road bike for the cost of your bike plus a tuneup. (I'm the last guy to get into bike snobbery, but a 29lb aluminum road bike with 2nd rate components is not generally a recipe for happy riding, especially when there are other options available.)

thanks for the links ill for sure try it out
and i'am looking for a new bike but until then i want to fix this one up and i think its fun to ride. i've ridden 15O miles on it so far and its a pretty good bike.
like you im not a bike snob and what not. the simplest things work for me. what do you think? waste of money?

When you say "the component moves but the chain remains on the same gear," are you saying that the front derailleur moves normally when you operate the shifter? I'm trying to imagine how this would even be possible (not doubting your words, though). A front derailleur is such a simple mechanism. Sure, it's normal to have rough shifting or even noisy shifting if the derailleur is out of adjustment; however, as long as the derailleur is able to move across the chainrings, it should still shift the chain.

How long has this been an issue? Did the problem slowly develop, or did it happen suddenly? Do you believe a fall or impact may have caused this?

Try parktool.com. Go to the section about installing and adjusting front derailleurs.

Disconnect the cable and start as if you were installing the derailleur for the very first time. Don't assume that it's angled correctly on the seat tube because there's a good chaice that's the source of your problem. Follow all of the steps in order because the sequence is important.

I must be missing some posts. I didn't see the one saying it was a 29 lbs bike, nor anything about the components.

He just stated that it was best to learn since the cost of an LBS tuneup would probably exceed the value of the bike. He's pretty close to correct if not spot on.

i know the derailluer moves but doesnt move the chain to the selected gears.
my wording is terrible i apologize. this just started a few days ago and i have had this bike for 6 months now. for the whole time i had it, it never fell or suffered a huge impact. thanks again for your help and patience.

If the derailleur worked when it was new and has recently stopped working, it suggests that the derailleur is not moving far enough to move the chain to the other chainwheels. That might be because the cable has stretched. Or it might be because the bolt that clamps the cable at the derailleur has loosened and the cable actually slips through the clamp. There could be other problems, too.

Cable stretch is normal around 100-200 miles. A quick adjustment of the front derailleur might be all you need.

Sort of fits, doesn't it.

im looking at the bike and the cable is definitely stretched. i did not even notice that..my bad!
so i just need to adjust the front derailuer?

Yes. Here's a link to Park Tools article that will give you all the steps you need:
http://parktool.com/repair/readhowto.asp?id=75
However, it sounds like all you need to do is loosen the cable clamp on the derailleur, pull out the slack, and then tighten the bolt.

Sounds like it doesn't move far enough. If you can turn the bike upside down and shift the derailer it should line up directly under gear. If it doesn't then you either have to take slack out of cable till they line up. the cable shoud have no slack when its in the lowest gear. If there is undo the nut that holds the cable on the front derailer and pull tighter with a pair of pliers till all slack is gone. Now try shifting thru gears again . Hopefully this fixed it. There are two adjustment screws on front derailer that will fine tune where the derailer stops for the lowest gear and one for the highest. IF this still doesn't work you will have to go to shop for final adjustment. It shouldn't be that hard, pretty simple to do if your mechanically inclined. Good Luck

thanks for the link!

and to everyone else thanks for the info, advice, and links
much appreciated!

Probably too late, but New Posters - please READ THIS.

so i fixed and tightened the cable and it shifts like a dream now!
thanks for all the help guys! :)