- 1 What happens when a bottom bracket breaks?
- 2 How long should a bottom bracket last?
- 3 How much does it cost to replace a bottom bracket?
- 4 Can you remove bottom bracket without tool?
- 5 What is the bottom bracket on a bike?
- 6 Why do bottom brackets fail?
- 7 Why is my bottom bracket clicking?
- 8 How often should a bottom bracket be serviced?
- 9 When should I replace my bottom bracket bearings?
- 10 Can I service a sealed bottom bracket?
- 11 Can you replace bottom bracket bearings?
Eventually your bearings will disintegrate and your BB will lose its ability to hold the spindle centred withing the BB shell, that will result in the crankset becoming wobbly, your chain will come off, your chainring might even go hit your chainstay and if you’re lucky it will happen at low speed.
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.
Between $30 and $50 plus the cost of parts. Though some shops may do the install for free or for a reduced fee if you buy the parts from them.
Almost anything can be taken apart without proper tools, including bottom brackets. it, but it can be done. The right tool for the job(any job) makes life much easier and will lower your frustration level by leaps and bounds.
The bottom bracket is the bearing system between the cranks. It sits inside the part of the frame called the bottom bracket shell. The bearings are held in the shell by an adaptor or a cup. The spindle connects the two cranks to one another and to the bearings.
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.
Most surprisingly, what often sounds like a bottom bracket creak is usually something else. Most of the time, the true cause is a loose chainring bolt. Tighten ’em up and that’ll quiet most creaks. After you check the chainring bolts, look at the pedals, crank bolts, seatpost and seat.
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. Around the three month mark is normally enough time, even in the best conditions for dirt to work its way into the small gaps and contact points around the crankset and bottom bracket area.
There’s really no periodic time period for BB replacement. You run em till they die. If the bearings are smooth without any perceptable play, then they are fine. When things eventually get contaminated (if they ever do), then you’ll notice roughness, crunchiness or significant play in the bearings.
Servicing them may be possible only if the design has the bearing seals exposed. Full one piece sealed cartridge style bottom brackets (octalink,square taper) are simply replace only. Depending on which sealed cartridge you have, you would need the appropriate tool to remove and replace them.
bottom brackets is the ability to replace the bearings without degrading the cups, and in the case of our thread-together bottom brackets, you can replace your bearings while leaving the cups in the frame.