How to Adjust the Front Derailleur Range on a Shimano Bike
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Proper adjustment of the front derailleur is important to shift your Shimano bicycle correctly. An improperly adjusted front derailleur can cause the chain to shift poorly, drag on the derailleur cage or even come off the chainring completely. Shimano derailleurs use a standard setup with a position clamp to hold the derailleur to the frame of your bike and two adjacent screws on top of the derailleur to adjust the low and high gear limits. With just a few hand tools and about 15 minutes, you can adjust your Shimano derailleur at home.
Adjust the position of the Shimano derailleur on the bicycle frame. Loosen the derailleur clamp on the frame with the Allen wrench just enough so that you can slide it up and down rotate it on the frame.
Lower the Shimano derailleur so that the derailleur cage is as close to the largest sprocket on the front chainring as possible without touching. Ensure that no part of the derailleur cage touches the sprocket. Adjust the angle of the derailleur cage to align with the sprockets on the front chainring. Tighten the positioning clamp.
Adjust the low gear limit. Shift the derailleurs to the largest sprocket on the rear freewheel or cassette and the smallest sprocket on the front chainring. Turn the low gear limit on the top of the Shimano derailleur with the Phillips head screwdriver to adjust the derailleur cage so that it prevents the chain from coming off the smallest sprocket.
Adjust the high gear limit. Shift the derailleurs to the smallest rear sprocket and the largest front chainring sprocket. Turn the high gear limit on the top of the Shimano derailleur to adjust the derailleur cage so that it just clears the chain on the largest sprocket.
Shift again to the largest sprocket on the rear gears and the smallest sprocket on the front chainring. Place your gear shifter in the lowest gear. Loosen the cable bolt on the front derailleur with the Allen wrench. Pull the shift cable to remove any slack. Tighten the cable bolt.
In Jacksonville, Fla., Frank Whittemore is a content strategist with over a decade of experience as a hospital corpsman in the U.S. Navy and a licensed paramedic. He has over 15 years experience writing for several Fortune 500 companies. Whittemore writes on topics in medicine, nature, science, technology, the arts, cuisine, travel and sports.