What is a peloton bottom bracket?

The bottom bracket is a bicycle component used to connect a bicycle's crankset to its frame, allowing it to rotate independently of the frame itself.

What does a bottom bracket on a bike do?

What is a bottom bracket? Your bottom bracket connects your cranks to your bike in such a way that they can rotate freely as you pedal and put power into the drivetrain. It is located in the bottom bracket shell which is where your frame's down tube, seat tube and chain stays all come together.

How do I know what my bottom bracket is?

To find out the size of bottom bracket needed, measure the inside of the bottom bracket shell in your frame, it will be 73mm, 70mm or 68mm. Some older frames may have Italian threaded bottom brackets, instead of the more modern English.

Why is it called a bottom bracket?

I think it's derived from the lugs used to hold the frame together as per Mick F's post. It then spilled over to refer to the mechanical bearing for the cranks. The actual 'bottom bracket' lug is now referred to as the 'bottom bracket shell' which rather cements the name 'bottom bracket' to the bearing for all time!

Are bottom brackets all the same size?

There are 4 widths available with BSA bottom brackets; 68mm, 73mm, 83mm or 100mm.

What is BB 92?

BB92 refers to the bottom bracket shell width, specifically: 41mm BB shell diameter. bearing with a 24mm internal diameter. 24mm diameter spindle on the crank.

Does bottom bracket make a difference?

(Click here to read BikeRadar's complete guide to bottom brackets.) According to Friction Facts' latest report: “No statistically significant difference exists showing a general advantage or disadvantage of a standard type under similar loading conditions.

How often should 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.

What is a threaded bottom bracket?

Threaded bottom brackets use a shell with internal threads to hold threaded parts. The frame shell may be threaded directly at the shell, or there may be an insert installed that has internal threads.

How long will a 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.

Should there be any play in the bottom bracket?

You are feeling for looseness or play in the cartridge sealed bearing BB. There shouldn't be any. If there is, you want to figure out why. Usually, it's as simple as something coming loose, like a cup or bearing, and tightening the bottom bracket will fix it.

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.

What is the most common bottom bracket?

BSA, or English threaded bottom bracket, is the most common threaded standard in use today. It uses a 68mm wide shell for road bikes, 73mm on mountain bikes, with a 34.8mm diameter shell. A few bike brands use an Italian threaded bottom bracket but these are rare.

Does bottom bracket spindle length matter?

The critical thing is your spindle length: as long as you can set up the correct chainline you will be good to go. But, again, best never to mix standards if you can at all avoid it. If you are looking to replace a cottered crank setup with a square taper setup, then look no further than a cartridge bottom bracket.

When I pedal my bike it makes a clicking noise?

A clicking noise is the most common sound your bike can make. It can be due to the rider pedaling fast, and the chain wants to jump up and down the rear cassette to accommodate the demands of the pedal. To identify the sound, you can slow down from pedaling and observe whether you still hear a sound.

Can I upgrade my bottom bracket?

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.

Can you service a sealed bottom bracket?

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.

Can I use a 68mm bottom bracket in a 73mm shell?

You could install it, but it will shift your chainline, shift the centerline of your feet, clearance issues might arise on the non-drive side, and you might be leaving some BB shell threads exposed on the non-drive side as well.

What is a 68 73 bottom bracket?

The 68mm and 73mm dimension measure the width of the bottom bracket on the frame of the bike with no BB installed, simply the width of the shell. Most road bikes that use a threaded bottom bracket measure 68mm wide and most cross country/trail mountain bikes measure 73mm.

Are all pf30 the same?

No they are not the same. But they are also not all that different. 6806 is a number you'll see describing the bearings used for both pf30 and BB30. This is the bearing category designation.

Are all hollowtech BB the same?

Since the spindle is part of the right crank, there's no issue of compatibility. All Hollowtech II cranks work with all Hollowtech II bearing units. Any crank that fits on one type of spindle will fit on all spindles of that type, but if the length is incorrect, the chainline/clearance will vary.

What is dub groupset?

In 2018, SRAM introduced mountain bike cranksets which use a new technology name DUB™ (Durable Unified Bottom Bracket). Meant to simplify frame BB and crankset compatibility across their product lines, it brought about yet another standard to understand.

What spindle length do I need?

If you have a Mid or a Spanish BB on your BMX Freestyle bike, you need the 5 5/8″ spindle. If you have an American BB on almost any style of frame, you need the 5 5/8″ spindle. If you are using the Outboard BB and the Spline Drive Sprocket, and you BB shell measures 68mm wide, you need the 5 5/8″ Spindle.

How do I know what size crankset to buy?

Crank length is measured from the centre of the bottom bracket axle to the centre of the pedal axle. If you're not sure what length the cranks on your bike are, the quickest way of finding out is typically to just look at the backside of your cranks, just below the pedal axle.