Help identifying problem with bike crankset/bottom bracket

Asked by: Terry Rickman

How do I know if my bike bottom bracket needs replacing?

Quote from video: But if it's just making noises. It might just need taking apart cleaning and servicing re-greasing and putting back. Together.

How do you test a bottom bracket?

Quote from video: 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.

Do all cranksets fit all bottom bracket?

In general terms, most cranksets can be fitted to a variety of bottom bracket shells, though much of this compatibility depends upon the availability of suitable hardware (see next section). Any incompatibilities that do arise are often related to the length and/or diameter of the crank axle.

Why is there play in my bottom bracket?

If there is play in your bottom bracket it means that the bearings are loose or worn out, it should be repaired soon because it will influence the whole drivetrain negatively, like sprockets and chain.

How long should a bottom bracket last on a bike?

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 often do bottom brackets need to be replaced?

What we found was again the basic bottom bracket on your bike from the factory isn’t going to last longer than 500 miles. Wheels Mfg brackets lasted substantially longer BUT the mileage varied greatly with climate and contamination. I maintain my bottom brackets every 1000 miles on my own bikes.

Why does my bike make a clunking noise when I pedal?

Loose cassette cogs can also be the culprit of clunking noise when pedaling the bike. To address loose cassette cogs, you need to use a cassette locking tool along with an adjustable wrench, and tighten the loose parts. This way, you can reduce or eliminate the clicking sounds.

Why are my cranks clicking?

In my experience, a rhythmic click that you can feel is usually from the pedals. It could also be the pedal spindle itself rather than the bolt that attaches to the crank arm. Check to see if the pedal wiggles at all. If it does, the spindle is your culprit.

Why does my bike make a clicking sound when I pedal?

A clicking noise often comes from your chain wanting to jump up or down a gear on the rear cassette. This can typically be fixed by adjusting the tension of the cable that runs from your shifter to your rear derailleur.

How do I know which crankset fits my bike?

The three most common crank lengths for bicycles are 170mm, 172.5mm and 175mm. What size your bike has will likely depend on what size the frame is. Small bikes tend to come with 170mm cranks, medium with 172.5mm and large with 175mm.

How do I know what crankset I have?

Print. Shimano cranks are all identified with model information above or surrounding the area on the backside of the pedal threads. For example; FC-6700/6750 = Shimano Ultegra. The crank length is often located in the same area, which is helpful to note before placing an order.

Is BB92 the same as PF92?

Trek is moving away from the BB90/95 system to what they call PF92, which is the same as a BB92 (41mm ID shell and 92mm width). Again, we recommend taking inner diameter and width measurements on the frame to determine exactly what standard the frame has.

How do I know if my bottom bracket bearings are bad?

Quote from video: And see if you can feel knocking in the bearings hard to see sometimes you can feel it. Another good indicator is to use some other senses like a sense of feel and some hearing.

Why is bottom bracket creaking?

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.

Do I need to grease the bottom bracket?

Quote from video: Похожие запросы

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 is bottom bracket creaking?

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.

Does bottom bracket make a difference?

The major benefit to using a threaded bottom bracket is how much more secure the fitment is compared to a press fit system that is more likely to creek. It’s also easier to work on as a home mechanic as you only need a special wrench to remove/install it.

How long do press fit bottom brackets last?

It’s been close to 2.5 years with it and between 10-15,000 miles. I did a lot of riding in the rain towards the end of 2016 so I imagine that shortened its life span. Any ideas how long a PF bottom bracket should last? I’d say mine last about 10k miles, with the caveat that each mile in winter counts for three.

Should you grease bottom bracket?

With the threads now clean and sharp the next step is to prepare them with a layer of good quality grease. The grease will enable a smooth fit between the cups and the frame, the grease will also reduce the chance of corrosion developing between the materials in the bottom bracket shell and those in the cups.

Do you grease a press fit bottom bracket?

Clean the inside of the BB shell with alcohol and a fresh rag. For an aluminium frame, a light coating of grease can prevent creaking. Most manufacturers advise not to use grease on a carbon frame but it’s unlikely to cause problems.