How do I know if my bottom bracket is worn?

Asked by: Kenneth Brandell

To check if your BB needs replacing, drop the chain off of the smallest chainring and spin the cranks. If there’s a side-to-side wobble, or feeling of grittiness, it’s time for a new one.

How do I know if my bottom bracket needs replacing?

Changes are likely to be compromised. As well. But if it's just making noises. It might just need taking apart cleaning and servicing re-greasing and putting back.

How often should a bottom bracket be replaced?

First, you should know when it’s best to service or clean your bottom bracket and crankset. At the very minimum, I do it about each season change, but normally more. Every three months or so I’ll take the cranks out and if it’s a threaded bb, I’ll remove the bb and do the full service.

How do you test a bottom bracket?

Little or no grease inside there or there's a lot of dirt or just the bearings are starting to go bad a lot of these have a silk cartridge bearing so bearings need to be replaced toss.

How do bottom brackets wear out?

bottom brackets do wear out over time. sometimes if your bottom bracket is making noise or not spinning freely you’ll have to take the bottom bracket out, regrease it and put it back in. if your going to buy a new bb you’ll need to know what kind and what size your bike uses.

Why does my bike creak when I pedal?

That creaky squeaking you hear as you pedal “could mean that [your bike] has a dry chain or bearings,” Yozell says. Cleaning and lubing your chain is usually a good place to start with any weird noise, but if it doesn’t solve the squeak, you may need to maintain or replace some bearings (see below).

Why is my bike crank clicking?

A clicking sound every third revolution of the pedal. Often indicates either stiff link or partially broken chain.

Should I grease my bottom bracket?

In the case of the bottom bracket, you will use the grease when you install it, whether it is threaded, press fit or similar, and in the same way when you install or clean the cranks. The point of contact of the cranks with the bottom bracket should be greased too.

Why do bottom brackets fail?

The fail by water and grit entering the bearing and causing the cartridge bearings to get loose. This is felt by poor shifting or chain rub, and finally the bearing can get very stiff if the balls jam up inside. External bearings can be cleaned and adjusted. Most have some sort of seal that can also be replaced.

Why does my bottom bracket click?

Most of the time, the true cause is a loose chainring bolt—tighten them up and that’ll quiet most creaks. After you check the chainring bolts and if you still hear the noise, look at your pedals, crank bolts, seatpost, and seat. By checking these first, you’ll save an hour of digging into your bottom bracket.

How long should a bike bottom bracket last?

As for a bottom bracket, on the low end, maybe 5000 miles. The basic Shimano one most people use (UN51/55/similar) can reasonably expect 10k+ miles. But sometimes you get unlucky and get a bottom bracket that lasts maybe 500 miles.

How long does a bicycle bottom bracket last?

They are still in use and come stock on many bicycles, especially lower end ones. These bottom bracket units can actually be pretty sturdy and can last for years or decades and the user pretty tosses in a new one when it seizes up in a rainstorm.

Do I need to replace bottom bracket when replacing crankset?

To answer your question specifically, yes cranksets require a specific bottom bracket, especially so the new offerings from SRAM and Shimano and others.

Is bottom bracket worth upgrading?

Reasons to go for the upgrade



Usually if both chainrings and the bottom bracket are worn out, you might as well upgrade to the new setup rather than buy all the parts for your old unit. Besides getting something that matches the rest of the parts, you’ll know you’re hammering on brand-new crankarms, too.

How do you fix a clicking bottom bracket?

Go through each of the chain ring bolts. And make sure that they're nice and tight OOP that one's a little bit loose. And tighten there so make sure they're all nice and tight.

Why does my bike clunk when I pedal hard?

The chain may be rubbing against the cage of the front derailleur, hence causing the noise. In that case, you need to trim the front derailleur. The chain will rub against the derailleur only in some gears since it changes its angle as you shift gears. That’s why your bike makes a clicking noise when pedaling hard.

How do I know if my cranks are worn out?

Now what you're looking out for is when the teeth of the ring. Start to become hooked. Like little shark's teeth. And that is a surefire sign that you need to replace the chain rings.

Why do my bike gears keep jumping?

Most of the time, a skipping chain is caused by cable stretch. In the first half dozen rides on a new bike your shift cables stretch the most. They can also stretch over time as you ride. Hippley explains, “It takes cable tension to open a derailleur, which shifts your chain between gears.

How long do bike cranks last?

As long as crank arms are checked regularly for tightness they should last for years and years. I have vintage Sugino Aero Tour (AT) crank arms that I have used for over twenty-five years without any wear to the square tapers. I’ve installed and worn out four or five chain ring sets using the same crank arms.

How do I know if my bike bearings are bad?

Worn out or dry bearings will feel rough, metallic and dry. Sometimes they’re so dry that if you pull your finger fast across the axle you can make the axle keep spinning because there’s no grease inside the bearings to slow it down.

What does a dry bearing sound like?

The classic sounds of a bad wheel bearing are cyclic chirping, squealing and/or growling noise. You can also tell that the sound is related to wheel bearings if it changes in proportion to vehicle speed. The sound can get worse with every turn, or it can disappear momentarily.

How often should bike bearings be replaced?

Normally every 12–18 months for the casual once a week rider. But I’ve seen bearings go in 6 months and others last 3 years. Drop that shock out and keep an eye out for yourself.

How often do bike bearings need to be replaced?

Normally, on a bike not left exposed to the elements 24/7, good-quality bike bearings should last 25-50,000 miles or so.

Why does my rear bike wheel wobble?

Bicycle wheels support your weight by placing a high amount of tension on the spokes that connect the rim to the wheel hub. Riding your bike regularly, over rough terrain or having an accident can cause the spokes to become tensioned unevenly, thus making the wheel wobble while riding.

How often should you grease bike hubs?

Clean and lube the chain (every couple of weeks). After every 10-20 hours of riding: check that all components are moving freely but without play. Check brake pads for wear.