Bicycle Mechanics - Fell on rear derailler and now it can't stay in gear.

Ok, I slipped on a wet manhole cover and went down on my right side, the rear derailler (not the piece that hangs down with all the cogs but the pod itself) took a hit. The thing won't stay in 4th and 6th anymore. Is there anything I can do at home before I take it to the LBS?

is there anything i can do

use non-indexed shifters?

i have found indexed shifting to be nothing but a headache.

I have shimano STI shifters, is that what you mean by indexed?

Yes, those are indexed and no, indexed shifting is not an inherent pain in the butt. Indexed just means that you click to each gear instead of trying to find it without the shifter stopping for you with each click.

As for your problem, it could be that the derailleur is just a bit tweaked and needs to be adjusted, though I fear that it is probably something bent somewhere. It's always hard to tell exactly what got pegged in any kind of fall, so it could be that your derailleur cage is bent a bit. Take a look at it from the top and see if, in the gears that work, the derailleur pulleys all line up with the cog that you're shifted in to. You might also be able to tell at that point if the cage is bent or, worse yet, the derailleur hanger is tweaked a bit.

Also check the derailleur cable and all of the housing that it runs in. If it's kinked from the fall it can keep the derailleur from going where it should. Make sure that the housing is setting where it should be, too. If it gets out of any of the braze ons on the frame, or is just sitting in one funny, it can cause freaky stuff.

Good luck.

I don't know what shimano STI is, but...

"what do you mean by indexed shifters"

http://www.sheldonbrown.com/gloss_i-l.html#index

sheldon brown explains it better than I can.

basically, with friction shifters it's pretty well impossible that you could find yourself unable to get your 4th and 6th gear to work. all you'd have to do is push on the shift lever a bit to adjust and then you'd be in the gear you wanted.

You can at least check to see whether anything is bent...first and foremost is whether the derailleur pulley cage is still parallel to the cogs. If not you've either bent the derailleur and it needs to be replaced, or you've bent the derailleur hanger and it either needs to be replaced or straightened, depending on whether it is integral to the frame or detachable. If the dropout includes an integral derailleur hanger that needs to be bent out, you gotta do this carefully to avoid cracking or breaking it. How you go about this will prob. depend on whether the frame is Al or Fe...

Hehe thanks for all the advice, turns out when my right shifter housing was bent towards me from the fall, that freed up a TINY TINY bit of slack from the cable and that was what was doing it cause silly me, I went ahead to try to fix the derailler without straightening out the shifter housing first. It seems to work now, still not as smooth as before but everything shifts ok.

BTW: anyone know how to loosen that piece of metal that holds the shifter to the bar so I don't have to force it back in place next time?

There should be an allen head bolt hidden in a recess on the underside of the shifter somewhere...

yeah, I think that bolt is only visible when you pull the brake lever. It's behind the lever there and pretty easy to get to as long as you know where to look.

Yeah pull back the flap on the shifter from the front of the shifter, and on the outside of the shifter behind the brake lever (if are facing it, it will be on the left side on the left shifter, right side on the right shifter) there is a hole for a 5mm (?) allen key... you pretty much need a T handle key to get ANY leverage on these stupid things since you have to use the long side of the L shaped key. If you can't find it PM me and I'll take a picture... its tricky to find.

Is it this thing here? How would I loosen + tighten it? Would that metal piece pop out if I loosen it too much?