Derailleur A is rotated too far counter-clockwise. Derailleur B is rotated too far clockwise. Notice rear end of cage is inward, toward mid bike plane. Derailleur C is acceptably aligned. Shift chain to outermost chainring and outermost rear sprocket. Sight chain from directly above chainrings. Consider the chain as representing a straight line. Compare this line to outer derailleur cage plate.
Outer cage plate and chain should be parallel. Keeping the cage and chain parallel will minimize the risk of the chain jumping off the outermost ring. If cage is not parallel, there will be a relatively large gap at either the back or the front end of the cage, and the chain may over shift. If derailleur cage needs to be rotated, note direction of desired rotation.
Release inner wire tension by shifting to the innermost chainring. Many clamps leave a slight marking on the frame. Use this scarring as a reference when changing height. It is also possible to use a pencil to make two reference marks on the frame, one for height and a second, vertical mark, to reference rotation. Use the marks to avoid inadvertently changing height. Loosen clamp bolt and slightly rotate in correct direction.
Use care not to change height. Tighten derailleur clamp bolt. Shift to outer chainring and observe rotation alignment. Repeat adjustment if necessary. Shift chain to innermost rear sprocket and innermost front chainring. Check inner wire tension. It should be fairly loose at this time.
If inner wire is taut, turn barrel adjuster clockwise into housing. The barrel adjuster is typically located where the cable housing enters the shift lever.
If barrel adjuster is already fully turned into housing, loosen inner wire pinch bolt, slacken inner wire and retighten bolt. Sight gap between inner chain plate and inner cage plate. Pedal bike slowly and continue to sight gap. Set clearance at tightest point in chainring rotation. Adjust L-screw so there is a small gap between inner cage and inner chain plate.
Pedal bike and check that chain is not rubbing cage as chainrings turn. Inspect for gap again and repeat until slight gap appears. If the gap appears larger than 1mm at its widest point, tighten the L-screw, in small increments, until the gap closes. Test the shift by shifting chain to next chainring then shift back to the innermost ring. Do not use the shift lever. Pull on the inner wire to shift the derailleur.
Using the lever may confuse limit screw issues with cable tension issues. If chain shifts quickly, limit screw setting is adequate. The gap will open wider than the 1mm target, but will still be as small as possible with adequate shifting. If chain is shifting beyond the inner ring and falls off the chainring, gap may be too large or cage alignment may be off. If chain ends up rubbing inner cage of derailleur, yet still drops off inner ring when shifting, other problems such as chain line or derailleur rotation exist.
Shift to outermost sprocket in rear and outermost front chainring. Inspect derailleur for mark indicating H-screw. Pull inner wire with hand to increase tension to insure derailleur is against H-screw.
Maintain full pressure on inner wire and check gap between chain and outer cage plate. Check gap again. This will narrow down the choices to just the hangers we currently offer for that brand. The first challenge I often face when trying to identify a hanger is getting a good photo. Below are examples of good and bad photos:. As you can see, the photos on the left let me clearly see the important features of the hanger while the photos on the right just lets me know that this bike really needs a new chain.
Not sure what Shimano Direct Mount rear derailleurs are? Click HERE for more information. As our replacement hanger offerings continue to increase, knowing how to quickly find a replacement means less time sourcing a replacement, and less time spent getting the repair done. How to Find the Correct Derailleur Hanger. Add to Cart. July 8, John White Derailleur Hangers, nobody gives them a second thought until they break one. Sometimes going up a level is actually not as good as subtle difference in chainrings can affect the shift quality.
Obviously if you want to you could upgrade your chainrings at the same time as your front mech, if for example the whole lot is a bit worn out. As modern chains get narrower to accommodate more and more cassette sprockets, front mechs have also changed width slightly. You will need a front mech that corresponds with the number of gears on your current groupset for it to work best ie. The majority of road groupsets have two front chainrings double but if you have three you triple you will need a different front mech.
Triple mechs three front chainrings have a larger rear plate than a standard mech as this helps the chain cope with the bigger change in chainring sizes from a very small front ring to a very large front ring. The bottom of the rear plate is also lower as the chain will have to drop further down to go on the smallest ring. Campagnolo Compact chainset-compatible mechs also have a larger rear plate to help cope with the large difference in chainring sizes, usually
0コメント