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.
What determines bottom bracket spindle length?
Since your chainline is constant, your bottom bracket spindle length depends only on your cranks, not your frame (with the exceptions noted above). Depending on the crank design, the spindle length can vary.
What length spindle 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.
Are all crank spindles the same length?
Spindle length varies depending on type of crank (road, Mountain, Triple, etc.). Two-piece system. Crank spindle is pressed into the drive side crank arm.
Which side of a bottom bracket spindle is longer?
Some BB are non-symmetrical: the spindle is longer on the drive side. Today it can be hard to find the proper non-symmetrical spindle BB for old cranks. One solution is to use bottom bracket spacers to push the BB over a few mm, effectively making a non-symmetrical BB.
26 related questions foundHow do I know my bottom bracket size?
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.
How long does a sealed bottom bracket last?
They can get "brinneled" or damaged in a crash or something, but 1500 miles is absurd. 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.
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.
When a bottom bracket size is listed as 1.37 x24 What does the 1.37 measurement refer to?
The bearings denote: 1.37 * 24. This means that the diameter of the thread is 1.37 inch and that it turns 24 times per inch. The diameter of a BSA bracket is between 33.6 and 33.9 mm.
What is crank spindle size?
Spindle size:
The majority of crank spindles come in either a 24mm or 30mm diameter.
What do numbers on bottom bracket mean?
The numbers ranging from 86 to 132 refer to the nominal width of the shell in millimeters, which is not related to the press fit of the bearings. These bottom brackets will vary in the width of the dust sleeve used for that different widths.
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 bottom bracket does giant use?
Giant Bicycles has a long collaboration with Shimano. It is no surprise that Giant's frames follow the BB86 and BB92 standard developed by Shimano.
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.
How do I know if my bottom bracket is Italian or English?
The key difference is in how the two thread into the bottom bracket shell. Like pedals, one side of a BSA standard bottom bracket shell is reverse (left) threaded, while both sides of an Italian standard bottom bracket shell are regularly (right) threaded.
What does the 30 in BB30 refer to?
While the "30" in BB30/PF30 references the inside diameter of the used, the numbers in BB86/92 and BB90/95 refer to the width of the frame's bottom bracket shell. The BB86/92 bottom bracket system uses a bearing pressed into a cup, which is then pressed into the frame.
Are all bottom bracket shells the same diameter?
Generally, your replacement cranks may have the same or smaller spindle diameter, and the same or longer spindle length than the system your bottom bracket is designed around. For example, a BB30/PF30 bottom bracket has the narrowest shell width of any of the standards, whilst being designed for large 30mm spindles.
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.
How do you know when your bottom bracket needs replacing?
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.
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.
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.
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.
What is a BB30 bottom bracket?
The BB30 bottom bracket allows you to pair 30mm spindle cranks to 42mm inner diameter bottom bracket shells. Cannondale pioneered this standard along with specially-designed cranks and many have found the benefits to them. Road versions have a 68mm width, MTB has 73mm.
What does BSA bottom bracket mean?
The short answer to your question is that when you see BSA in terms of a bottom bracket, it refers to a 68 or 73mm shell with 1.370/1.375″ x 24 TPI threads and a left hand thread on the drive side cup.
