[fourgivn1]

When I'm on the middle of the 3 gears (in the front...I forget the 'technical' name for it...I'm a newbie, so shoot me ), the bike seems to want to shift itself. I'm guessing it's the tension on the shifter cable, and the bike store guy seems to think the same. This being said, is there anything else that can cause this? The bike is somewhat new (2 months, although I've pounded it ) so I don't think it's an incorrectly installed derailleur or something. Any help would be appreciated.

 

[BikeGeek]

So, you're in the middle chainring and it's trying to shift. In the front or back?

If you're getting chatter in the back like the chain wants to shift, that can usually be fixed by using the adjuster on the rear derailleur.

If it's in the front...is the chain rubbing the derailleur cage? Where on the rear gears when the front is trying to shift. I've never had this problem so I'm just trying to think through what it could be.

 

[fourgivn1]

...should have clarified. Yeah, 'chatter' is the best way to put it. The front is just fine when I shift to any of the 3 gears.....however, when I'm in the middle gear, I get a LOT of chatter in the back, and sometimes it actually shifts. Hope that helps.

 

[BikeGeek]

Originally posted by fourgivn1
...should have clarified. Yeah, 'chatter' is the best way to put it. The front is just fine when I shift to any of the 3 gears.....however, when I'm in the middle gear, I get a LOT of chatter in the back, and sometimes it actually shifts. Hope that helps.

Yeah, it sounds like maybe your rear derailleur is out of alignment. On the derailleur, where the cable enters it, there should be a small knob (depending on the brand/model). Turning the knob adjusts the derailleur in small amounts one way or the other. Sometimes you can get down behind your bike and actually see which direction the derailleur needs to go in order to be centered over the gear that you are in.

If that doesn't work, your derailleur hanger may be bent. If it's a small amount, it may not be noticible. Your best bet is to have the LBS put a derailleur alignment tool on it to check it out.

 

[VTinCT]

Hey man. BG is right on with the tensioner. Since the bike is new, there will have been some cable stretch, so that little bit of slack will need to be taken in.

Also, you should go ahead and check your limit screws (Hi/Low on the r-derailer), to be sure they're set properly. If you did not get the instructions with your bike, just post what derailer it is and one of us will get you through it...its pretty easy with some patience. Finiky rive trains will make you crazy faster than a $hitty boss...or constipation....or biker's itch...or....you get it

 

[fourgivn1]

....rear derailleur. And I'm no idiot either. Not that anyone was saying I was, or that I'm a pro (FAR from that *L*) but heck, I do repair PC's for a living, and used to run reactors, so I can follow directions pretty well, and I'm a purty smart feller too. :