Top derailleur not returning to first position

Mark:

First of all, make sure that you are not over or under shifting. The chain has to be positioned exactly over the gear that you are trying to use. If you hear derailleur or chain noise The derailleur is not "in gear" and you have to adjust your shifter to eliminate noise. The derailleur must be adjusted so that the chain is parallel to the gear cluster in each gear. If the chain is twisted at all, it will skip gears. Check your rear derailleur to ensure it is pointing the chain directly at the front gear cluster. Check the front derailleur to see that it is pointing the chain directly at the rear derailleur. While you are at it... clean the derailleurs with alcohol and lube them with a light weight oil. Check the derailleur stops (small screws next to the cable clamp on the derailleur). Have the bikes rear tire off of the ground and pedal the bike with one hand while shifting with the other hand and you can see what the derailleur is doing. adjust the stops so that you can not shift the chain off of the gear cluster in high or low gear. You may have to adjust the cable length at the derailleur cable clamp, and at the adjusters on the shifter to get the exact adjustment that you want. It will take some time to properly adjust your derailleurs, but it is worth it when you can ride without your derailleurs acting up.

Derailleurs have a return spring in them that will always return them to the smaller cog (whether it is front or rear). The derailleur cable resists this spring tension. If your front der. is on the large ring and will not shift to a smaller ring then it could be a couple things. First, too much cable tension preventing the spring from returning the derailleur to a smaller cog. Second, you low limit screw is set too far in so the derailleur cannot travel back to a lower gear. This will be evident if you shift to a smaller cog, the derailleur does not move and the cable becomes slack. Third, something else is preventing the derailleur from moving, perhaps the derailleur was moved when installing the new crankset and it is getting hung up on a tooth of the large chainring, there could be some foreign matter lodged in the derailleur spring preventing it from operating, the spring could have broken so there is no longer enough tension to move the derailleur back to it's "home" position. Good luck.

Hi,

All shimano derailleurs have two small screws located on the mechanism itself that allow you to adjust the position of the derailleur relative to the gears. The top one adhusts how far towards the wheel the chain can go and the bottom of the two adjusts how far towards the stop it goes.

Put the bike on a stand or just prop it up so the rear wheel can spin freely when you turn the pedals by hand

Put the shifter in the highest gear and turn the pedals, the adjust the top screw until it enters the top gear, you may need to adjust the cable tension also to do this.

Once you have it going easily into and out of the top gear adjust the bottom screw so that it easily goes into the bottom gear.

You should be done! Don't forget that for the first few rides the cable will stretch out a little so you may need to tinker with those screws a couple more times.

Hope this helps:)

This website might help you also http://sheldonbrown.com/derailer-adjustment.html

http://www.parktool.com/blog/repair-help/front-derailleur-adjustments

If you mean that your gears are slipping by means of the chain improperly engaging or riding along the walls of the cassettes outer gears, you can adjust the rear derailleur by means of a few tools. You can control how far in and out the derailleur moves by adjusting the two limit screws with either a proper fitting allen wrench or a small phillips head screwdriver. This won't have any affect on the inside gears but if it slips on the outer-most gear, it may help. You can then adjust the cable pull by hand on the adjusting knarp if present on the derailleur. It is the little (sometimes plastic shrouded) adjusting mechanism which the cable housing seats itself in. It is found directly on the derailleur and commonly on the shifter being used with the derailleur. You can rotate the knarp clockwise to loosen the cable or counter-clockwise to tighten. If the knarp has been threaded all the way in or too far out, you can return it to its original position and tighten or loosen the shifter cable manually using either a 5mm allen wrench, a 9mm box end wrench, or a specialty tool. Depending on the positioning of the derailleur and its design, tightening or loosening the cable will affect the position at which it is placed for each related gear. With a little bit of time and examining, you can hopefully figure out the most effective setting which would hopefully allow the derailleur to engage each individual gear without hesitation. To tell wether you adjusted it properly, follow these guidelines. 1, Make sure each gear being engaged is reflected on the position of the shifter. 2, When shifting gears by hand, the chain should not drop below the selected gear nor should it hesitate to move into the selected gear from its previous gear. 3, Check the limit screws position on the derailleur and make sure it is adjusted so your low and high gears are engaged without the chain slipping past the low or high gear, and slipping of the cassette. 4, When tuning the rear derailleur, make sure you account for the change in the chains travel path due to front chainwheel shifts.

- If the derailleur is not an issue, and you attempted to adjust it with similar results afterwards, look over the drivetrain of the bike closely while it is in motion and try to see the exact component that seems to be the source of the problem. I will be happy to dig deeper into this problem if you wish to ask another question regarding this issue. Good luck.

The deraileur should have two screws on the right side (facing you when you look at the derailleur) try making the screws tighter or looser to tune the derailleur.

I had to use Google translate, as I do not read German. However, I think you are asking which derailleur pulley wheels go on the top and bottom. I would suggest Googling for images of your particular derailleur. It appears to me that the large pulley wheel goes in the upper position, and the small in the lower.

They are basically stop screws, the stop the derailleur from pushing the chain off the sprockets in both directions,You can adjust these so you don't have to worry about losing a chain or grinding a chain, trying to get it in position.

Try this first:
Shift into the small ring and release the cable. Pull it tight (with pliers) and re-tighten the cable. It should shift now. If it doesn't, the solution is a little time consuming, so i apologize in advance.
First, flip your bike onto the bars and saddle. Now shift into the small chainring and your lowest cassette cog (the largest in number of teeth). Release the cable from the front derailleur and set the adjustment knob for the front derailleur to its center point. You should find it on your shifter. Now adjust the "L" setting on the derailleur while turning the crank so that its stop sets it in a position where it just skims the chain but does not touch it. Now pull the cable taut and re-clamp the cable. Shift into the middle ring and shift the rear derailleur to its highest and lowest gears, making sure the chain does not rub the front derailleur. If it does rub (it will be in either the lowest or highest cog on the cassette), adjust the front derailleur by way of the adjustment knob to clear the rub. Then shift into the big ring and you should have no problem. Set the "H" stop if necessary.

Go to Parktool.com it's real easy. good luck