What is JIS bottom bracket?

What is JIS bottom bracket?

J.I.S. is the Japanese Industrial Standard, and is generally used on square taper cranks made in Asia. All of the common black spindles identified with standard numbering use the J. I. S. taper. Many of these have a threaded boss for a nut on each end, rather than being hollow and threaded internally for a bolt. J.I.S.

Are Shimano bottom brackets JIS?

Shimano and most other Asian manufacturers employ the JIS standard. Campagnolo and other European manufacturers use ISO. JIS square taper bottom brackets are easily distinguished due to their black color and standard numbering system.

What is the difference between JIS and ISO square taper?

ISO and JIS are very similar – the angle of the taper is the same, but the ISO spindle ends are a little slimmer. In a pinch, you sometimes can use a JIS spindle with an ISO crank. To compensate for the wider JIS taper, select a spindle that is about 1-2 mm shorter. The taper of your cranks: JIS or ISO.

How tight should bottom bracket?

If your bottom bracket’s threads are particularly tight, you might want to have the them chased to see if they can be freed up. Generally speaking, with bottom bracket thread, you don’t want them ‘baggy’ and loose, or annoyingly tight, somewhere in between.

What is the difference between ISO and JIS standards?

In addition, JIS uses accuracy class designations of “C” for positioning screws and “Ct” for transport screws, whereas the DIN ISO standard uses the designations “P” for positioning screws and “T” for transport screws. The JIS B1192-1997 standard also includes several accuracy classes that DIN ISO 3408 doesn’t address.

What is the difference between JIS and ISO?

Are JIS and ISO Taper Bottom Brackets Compatible? Whilst both versions of the square taper Bottom Bracket look the same, the European made ISO square taper spindles are slightly longer, tapering down to a small end than the Japanese Industry Standard (JIS) Bottom Bracket spindles do.

What is BB30 bottom bracket?

The term BB30 was an early term in the history of this standard and refers to the 30mm diameter of the spindle used at that time. However, bottom bracket bearings are available in this standard for 28.99mm, 24mm and 22/24mm spindle systems.

Should I grease my bottom bracket?

when the bearings are rough and loose feeling (like the op stated) they need to be replaced. new grease won’t cure worn out bearings and races. so, to answer the original question, no, you don’t need to lube the bottom bracket.