Problem With Shimano 7 Speed
 

Hello all, this is probably a horribly noob question, but I just can't figure this out! I received a bike about 4 years ago, and rode it pretty avidly, but stopped when a problem arose. I want to start riding again, so I decided to drag the bike out of storage and try to fix it - but as already stated, I can't figure it out! The chain has slipped off of the seven speed shifting mechanism. If any of you know how to fix this, I would love to fix it myself! If it's something that needs to be done by a shop however, there's a shop here in town that I could take it to if need be. Let me know what you guys think, and thanks in advance!

Picture of the assembly:
http://i103.photobucket.com/albums/m...n/100_0410.jpg

-Zach

Looks like a poor quality derailleur spring or a poorly adjusted derailleur has sucked the chain into the spokes. You're lucky, doesn't look like any damaged spokes (similar thing happened to me recently which broke a spoke, bent another one and destroyed the derailleur). Try taking the chain off the front chainrings and lifting the chain backward over the sprocket cluster. If it won't budge, don't force it - you might end up wrecking more than has already happened! In that case you may need to remove the wheel to free the chain, but by then it's a good chance something else has been taken out as well :(

You need the derailleur hanger straightened, which is best done by a shop with the proper guage/tool. That twisted rear derailleur will need to be replaced with another 7 or 8-speed one.
Wheel should be checked for broken spokes and trueness, and the chain for bent or twisted links.

The chain isn't caught in the spokes, as it may look in the picture. The chain is free moving and looks good to me (although I'm no expert). No spokes look damaged from what I can see. Is the derailleur the all silver piece that moves freely, or is it the part with the red "Shimano" label in the picture?

If you guys need any other pics, I'm glad to take them. The one above was taken quickly and is horrible quality, so my bad for making this any harder than it may already be!

-Zach

Are there no jockey wheels on that derailleur?

I hate to say it, but I have no idea what that means. :)

-Zach

Google either Park Tools web site (bicycle repair tools) or Sheldon Browns site (RIP), for pictures and descriptions of the rear deraileur. These all work the same regardless of the number of speeds on the bike.
I agree it looks like the deraileur may be missing parts. That would explain how the chain came out of the derailleur. You need either a properly working bike, a repair book, or a repair web site to see how this should work.

You may want to take it in for fixing since you aren't sure how to do it.
You might want to check into getting one of these so you can pickup a better rear derailleur also since it looks like it will need to be replaced. http://www.jtgraphics.net/images/tan...ar-bracket.jpg
http://sheldonbrown.com/harris $3.99 part

The Derailleur is the part that moves in and out to align the chain on the sprockets, which are the things with teeth. There should be two small pulleys or sprockets on the derailler but it looks like they grenaded and spun the derailler around. Loosen the bolt that holds the cable on the derailleur and remove the cable, loosen the bolt that removes the derailleur and let it slide down the chain. look for damage to the hanger, which is the tab on the frame that the derailleur bolts to. It might be bent and need straightening or be damaged. Check the chain for any kinks or bends or twists. Let us know what you find...

"The only stupid question is the one you didn't ask"

The chain isn't even attached to the derailler from what I can see. I'll take some better pics a bit later today. It does look a bit odd though, so I'm assuming something has to be bent, missing, or out of place. Who knows, but hopefully you guys will be able to help!

If I did have to wind up taking this to a shop, how much would it cost to get fixed?

Look at another bike and you'll see what's wrong/missing

That derailleur is going to need some professional help. Take it to a good shop.

Al

Yep -- it looks like you need some new parts. :eek:

Did that derailleur explode when you were on the bike? I ask, because ummmmm... at some point in time, that derailleur exploded.

The following is what a derailleur looks like when it hasn't exploded and doubled back on itself. You'll notice that yours doesn't look like the one below.

http://upload.wikimedia.org/wikipedi...derailleur.jpg

Oh wow! Well that would sure explain why I was having such a hard time fixing it! :P

So, what would you guys recommend from here? If I'm going to have to be purchasing new parts, what should I look into and what kind of prices are available? I was hoping to have this fixed by the weekend, but it sounds like that may not happen. Tomorrow I'll take it to a reputable bike shop in my area and perhaps hand it over to them to fix!