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Are Hollowtech II bottom bracket normal?

5 min read

Asked by: James Stafford

What is hollowtech II?

HOLLOWTECH technology is an ultra-lightweight hollow crankarm created by SHIMANO with the company’s own proprietary forging technology that also maintains rigidity.

When did hollowtech 2 come out?

Shimano’s Hollowtech II cranks, unveiled in 2003, essentially ushered in the current era of crank design by integrating the axle into the design of the crank. From that point on, the weight, stiffness and reliability of cranks improved, plus, they were easier to install and service.

Are all hollowtech BB the same?

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.

How do I know my bottom bracket is standard?

Quote from video: Found at any point here by hitting the information icon in the corner. The bottom bracket is the bearing system between your bicycles cranks.

What diameter is hollowtech 2?

Crankset Standards

Crankset Spindle Diameter Bearings
Shimano HollowTech II 24mm 24×37 (Drive) 24×37 (Non-Drive)
GXP 24mm/22mm 24×37 (Drive) 22×37 (Non-Drive)
SRAM DUB 29mm 29×42
BB30 30mm 6806 (Drive) 6806 (Non-Drive)

How do you install a Shimano hollowtech 2 bottom bracket?

Quote from video: Place the required o rings on the spindle. Next apply lubricant to the thread in the frame of the bank. Slide the bottom bracket into the frame and thread it into place in a counterclockwise.

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.

When should I replace bottom bracket?

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.

What cranks are compatible with hollowtech?

2. Compatibility of cranksets and different BBs

Crankset standard BB compatibility
Square taper Threaded (british, italian)
Octalink Threaded (british, italian)
ISIS Threaded (british, italian)
Hollowtech II Threaded (british, italian), BB30, BB30A, PF30, OSBB, BB86, BB90, BB92, BB95, BBright, BB386EVO,

How long do bottom brackets 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.

Do bottom brackets make a difference?

In addition, the average drag for all of the bottom brackets tested is just 0.77W. In other words, bottom brackets do different significantly drag-wise in terms of percentages but as far as actual watts are concerned, we’re talking relatively small numbers here that most general cyclists aren’t likely to notice.

What BB does Shimano use?

Shimano BB86

Shimano developed its press-fit standard using 41mm diameter bearing cups with an 86.5mm wide bottom bracket shell for the road, and 89.5 or 92mm for mountain bike.

What is the standard bottom bracket size?

The common threaded bottom bracket uses cups or adapters with the thread specification of 1.37″ x 24 threads per inch (approximately 34.8mm diameter). The most commonly used term for this standard is “English” threading, sometimes abbreviated as ENG.

Are all bottom brackets the same size?

There are 4 widths available with BSA bottom brackets; 68mm, 73mm, 83mm or 100mm. This bottom bracket clearly shows you on the outside what bearings have been fitted to the bike. For road bikes, a BSA bottom bracket is always 68 mm wide. Other sizes, and particularly the 73 mm width, is commonplace with mountain bikes.

Does bottom bracket spindle length matter?

Quote from video: Похожие запросы

What does BSA bottom bracket stand for?

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.

Is tiagra a hollowtech?

Taking many features from pro-level equipment, the Shimano Tiagra 4700 Hollowtech II Semi-compact Chainset offers the rider ease of installation, durability, and enhanced performance.

How do I identify a Shimano crank?

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.

How does a bottom bracket work?

The bottom bracket on a bicycle connects the crankset (chainset) to the bicycle and allows the crankset to rotate freely. It contains a spindle to which the crankset attaches, and the bearings that allow the spindle and crankset to rotate. The chainrings and pedals attach to the cranks.

How long do bottom brackets 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.

Does changing 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.