Set indexing only after completing all adjustment above. If the shift lever has two distinctive stops or clicks, it is indexing. The front derailleur should shift the chain between chainrings without throwing the chain off the extreme outer and inner rings.
It is possible that the front derailleur will rub the chain slightly even on properly adjusted bikes. This is likely on some bikes when riding in the largest sprocket in front and the smallest cog in back. As the bike is pedaled with force the frame flexes and moves the chainrings side to side, which cause an intermittent rubbing noise.
Loosening the H-limit would move the front cage out more, and may stop the rubbing, but it may also cause the chain to shift over the largest ring and come off. If all aspects of front derailleur adjustments are correct on this bike, the rider is simply exceeding the engineering and design capabilities of the machine. Rear Derailleur Adjustment View Article. Trade Resources. Repair Stand — holds bike secure for easy work Hex wrenches as needed Screwdriver 2 Phillips or straight blade Light lubricant Derailleur cable inner wire and housing as needed Caliper or metric ruler Cable end caps and housing end caps as needed Rags.
Inspect height alignment of front derailleur. The outer cage plate must be positioned over the largest chainring when viewing height. Simply grab the exposed front derailleur inner wire until outer cage plate is directly over outer chainring teeth. Use care to not shift the derailleur cage past this point. Note height and direction of change needed. It is then necessary to relax the cable to loosen the mounting bolt and raise or lower the height as needed.
The gap between the teeth of the outer chainring and lower edge of the outer cage plate should be mm, about the thickness of a penny.
Using a penny or a dime as a feeler gauge, fit it between the chainring teeth and the cage plate. It should just fit between the teeth and plate. To lower cage, release inner wire tension completely by shifting to innermost chainring. Note angle of outer cage plate relative to chainring. Front derailleur clamps typically leave a mark on the frame, which is useful as a reference when changing height. Loosen derailleur clamp bolt, change derailleur height, and return cage to same rotation relative to chainring.
Tighten clamp bolt. Move outer cage plate over outer chainring, and check height again. Repeat this process until cage plate height is mm above outer chainring.
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.
At this point you still need to be able to move it by hand. Check to make sure the cage of the derailleur will clear the large chain-ring when the the hinge extends. Take up the slack on the shifter cable with pliers and tighten down the bolt on the retaining clamp. Thread the shift cable back into the derailleur, pull it tight and tighten the anchor bolt so the cable flattens.
Then find a bare stretch of cable and give it a good pull to make sure the cable is seated and has no slack. Then loosen the cable, pull it tight again and re-tighten it. If your chain is still on the bike, undo the tail screw on the derailleur cage and flex the cage to pull the chain through. Then re-install and tighten the tail screw again. If you have removed the chain, re-route the chain through the derailleur cage and reconnect it. While changing gears if you have to force them to change, the derailleur was put on incorrectly.
The casing for your cables can break. Run through the entire range of rear sprockets to make sure the chain does not rub on either side of the front derailleur cage. Turn the bike to standing position. Use half turns while adjusting.
For height adjustment, the bottom edge of the outside derailleur cage should sit approximately 2mm above the top of the teeth on the largest chain-ring. For the angle adjustment, rotate the derailleur until the cage is parallel with your chain-rings. Adjust the derailleur limiting screws and cable tightness as needed. Maintenance includes: Changing through the gears one or two at a time.
Making the chain ride up and engage with another cog is a combination of your smooth pedalling action and a crisp clean shift. Sometimes you need to press your lever or twist your wrist just that little bit more before you release it.
Aim for a good firm shift rather than a cautious hesitant one. With derailleur gears, you cannot change gear when you are stationery and changing out of the wrong gear whilst you are going slowly or pedalling up a hill for example can be very difficult.
You need to be in the right gear for the moment. Always remember to change down to a low gear before coming to a stop or hitting a hill. Cancel: I did not complete this guide.
One other person completed this guide. Badges: 5. Fix Your Stuff Community Store. Difficulty Moderate. Steps 8.
Time Required 30 minutes. Sections 1. Bicycle Front Derailleur 8 steps. Flags 0. Introduction The front derailleur is the mechanism that shifts the chain on a bike with more than one front chain-ring.
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