Why does bicycle chain fall off

Because the old one will have stretched, your new one should be a little bit shorter. If the chain is too long and has too much slack, you will probably need to remove a couple of links to obtain the proper length.

A chain that is at the proper length should be able to reach the large-large gear combination, and not have the rear derailleur overlapping itself when in the small-small gear combination. Derailleur bike chains are designed to allow the chain to transition from one sprocket to the other during shifts. As the number of gears in the cassette increases i.

To allow for proper shifting, chains follow this trend and also get narrower to accommodate the narrower spacing. While most cases are nowhere near as severe as the one pictured here, a bent chainring or even chainring tooth can be your source of dropped chains. Accidents are the most common cause, however, a bike that simply topples and strikes a hard surface could be enough to bend a chainring tooth. Inspect the chainring by backpedaling and seeing the distance between the chainring and frame changes.

If you feel a sudden change in resistance pushing back against your hand it means that the ring is bent. Badly bent chainrings will have a very apparent wobble to them while turning. You can try to use a wrench to gently bend the chainring back into place, or they also make specialized chainring straightener tools as well.

Not only can poor alignment of the rear derailleur lead to noisy shifts, but it can also lead to chain drops in severe cases of misalignment. Limit screws control how far the derailleur can travel inward and outward. They prevent the chain from going into the spokes or frame. Inspect your rear derailleur hanger to see if it has been bent. It should be perfectly parallel to the cogs , and not bent inwards or outwards.

Be aware that this process could cause the hanger to break, so it helps to keep a spare on hand. With the increasing popularity of one-by drivetrains, clutches were introduced to help adjust the tension on the rear derailleur. This helps keep more tension on the chain and prevent it from bouncing as much.

If you suspect this to be the case, get in touch with your local bike shop or the manufacturer as the part may be under warranty and can be replaced free of charge.

Step 6: Before you hit the trail, you may want to shift out of the gears you used to get the chain back on. Shift into a moderate gear, and take a spin. Hopefully some of these pointers have helped quell your frustration and get you back on the trail. If something in your drivetrain is still amiss, consult with a professional bicycle mechanic as needed to fully resolve your mechanical issue.

This growing compilation of videos is focused on providing advanced technical tips in a way […]. Reading Time: 5 minutes Your first ride on a shiny new bike can be flat out ruined by the smallest of details. Such as loose chain, inaccurate front or lower derailleur, too long chain, worn-out chain components, etc. At this point, you will need a chain tool to fix the chain. Also, it is possible to fix the bike chain only with a hammer and pliers.

But, the chain tool makes things easier while on the street. If your electric bike chain started falling off frequently, that means some setup may change. So, the first thing you have to do is make sure the drivetrain bolts are tight. Also, inspect that everything is in the place and not get whacked or the rear wheel is correctly positioned.

Hang the bike from a stand or turn it back upside down. It will make the fixing process easier and keep the bike steady while working on it. The bike should rest on its seat and handlebars. Look out for the gear the bike is on and where the chain is resting now. For getting slack on the chain, push the arm of the rear derailleur toward the handlebars. Use another hand for sliding the chain back on the right gear.

Drape the chain on the right rear gear using fingers. When you have some teeth in place, slowly release the derailleur. Now, for 1 full rotation backward slowly pedal the bike with the hands. It will make sure the chain is securely in place. Drivetrains are the reason for back wheel moving. It consists of chainrings, a cassette, a rear derailleur, and the chain itself.

The drivetrain wears out and makes the chin fall down because of the collected dirt, grime, and grit. Adequate and frequent maintenance or cleaning of the drivetrain can maximize the lifespan of the bike.