How To Change Euro Bottom Bracket On a Bmx Bike

Updated on August 18, 2022

How To Change Euro Bottom Bracket On a Bmx Bike

BMX is like a massive hydra with many heads. The golden fleece of freestyle will be at your feet, ready to snap at you and slap you in the face as you ride up on ugly great legs…

There are a lot of different BMX sub-genres these days, which I was trying to get through in my extremely laboured manner. It is possible to skate on the street, in the ‘dirt’ or on a ‘ramp’; there are multi-million dollar training facilities and skateparks; and you can buy shoes and clothing. What about the bike you actually ride, which gets a lot of attention? It’s never been cool to obsess over your bike, but isn’t it essential to your daily commute? For the most part, we don’t want to go back to the ’80s-era bikes for serious riding. Is it possible to imagine Stephen Murray attempting a backflip on a super-burner? In the last two decades, technology has advanced significantly, but there have also been setbacks. Anybody got an answer on suspension forks? Any time BMX is popular — and let’s face it, it is — a businessperson will perceive an opportunity to benefit from it. You should not consider the words of a businessman who is also a rider as gospel. I hope this column will help you decide whether or not your next bike’s new and upcoming features are truly beneficial or just a marketing stunt.. Insofar as I can, I shall present both the arguments for and against both sides of any given issue. Nevertheless, please keep in mind that I am just another rider out to fleece the youngsters of their hard-earned money.

The hotly debated topic of European bottom brackets is the obvious focus of the first column. To begin, some context is in order. Before freestyle bicycles were invented, all bicycles were unique. Many of them were French and had a large wheel and a smaller one. The forks of these pennyfarthings had a “bearing” at the bottom of each leg for the hub to run in, with a crank arm attached to the end of each crank arm. It’s a plain, lackadaisical, and uninspiring piece of work. Eventually, people grew tired of slamming their faces against the pavement after hitting a stone or stopping, and the “safety” bicycle was born. There were no standard parts because every manufacturer did things their own way. Manufacturers sought out ways to improve their products, thus they began employing ball bearings in place of brass bushings and pneumatic tyres, among other innovations.

Standardization of the inner diameter and length of bottom bracket tubes took time, with the average being about 3 inches long and 1.5 inches in diameter. In the end, there was still a lot of inconsistency between the various threads used by the French, British, and Italians. This is the same thread that a conventional 16-tooth freewheel uses, and it became the standard throughout time. Today, all road and mountain bikes use this same bottom bracket, which is internally-threaded with a one and three-eighths-inch diameter and 24-threads per inch. It is still available in two sizes, 68 and 73 millimetres broad. This is the Euro BB that’s making all the fuss right now.

Eventually, cranks were one of the most expensive pieces of a bicycle to manufacture. They required to be built in several pieces because they were so heavily loaded in various bending and torsion modes. So, someone came up with the brilliant notion of manufacturing the entire caboodle in one go. For the crank arms and spindle, all you need to do is forge a single piece of bent steel. Unfortunately, a standard frame’s short bottom bracket shell would not allow it to pass. The simplest answer was to create one that was enormous enough to fit through the opening. For simplicity, BMX pioneers chose the standard when they built their first bikes because it was widely accepted.

Young riders’ bikes have traditionally been one of the most technologically competitive sections in BMX. However, for an adult racing cyclist who weighs 150lbs, even a small amount of weight on the bike can have a major impact on the performance of a younger rider, as well as his father! In my biassed and cynical view, I’m betting that a lot of happy dads watched their kids come in second place week after week at the local track and really wanted to help. Whatever the case may be, in their quest for an advantage over the competition, the small-wheeled motorcycles became significantly more “techno” in nature. Aluminum, titanium, and carbon fibre quickly became ubiquitous on the bikes of the little men since they were lighter and less prone to breaking under the weight of small riders hitting small jumps. Small European bottom brackets also became popular. This seems to have been an important factor in many fathers’ aspirations for glory.

In the last year or two, there has been an undercurrent of discontent in our area. Some bikers are concerned about the weight of their 40-pound street bikes. Having had a peg go through my hand when my bike landed on it from four feet, I can sympathise with the desire to lose a few pounds. You can save a few more ounces by using sleeved pegs, 36 spoke wheels, and a few more pounds by using 8-pound frames, but you’ll lose a lot of strength in the process, and you’ll have to pay for it in the long run. After all, it was just a matter of time before someone began to investigate the entire crank and bottom bracket region. With Profile cranks being quite popular with mountain riders, you can buy cups to fit either Euro or BMX bottom brackets. The BMX version weights 6.8 ounces, however the Euro version weighs 4.6 ounces, which is significantly lighter. Take a look at the shell as well. A BMX bottom bracket shell is 7.7 ounces thick whereas the Euro shell is only 2.5 ounces thick.

As a result, moving to the new standard allows you to keep your standard Profile cranks while also saving about 25 grammes in weight. Depending on the thickness of the bottom bracket shells, the savings could be much more substantial. If the cups are screwed in like a ballet of precision technology rather than being belted in with a hammer, and are then locked in place at the exact position with a lock-ring, it looks much better.

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What exactly do I have to learn?

Detailed Instructions on How to Remove and Install a Crank
Tool Selection for the Bottom Bracket With Threaded and Thread-Together, see the article

What tools do I need?

a device for removing the bottom bracket
Tightening tool
Adjustable Wrench PAW-12, 12 Inches
PPL-1 PolyLube 1000TM Lubricant is used for thread preparation (Tube)
TLR-1 Medium Strength Threadlocker ASC-1 Anti-Seize Compound

The spindle is coupled to one of the cranks of the two-piece crankset, which has a left and right arm. The bottom bracket shell contains bearings through which the spindle travels.

In a typical three-piece crankset, the bearing and spindle are incorporated into the left and right arms.

Bottom bracket shells commonly use a “English” threading pattern. The cup on the left has a right-hand thread, which tightens clockwise and loosens counterclockwise. In order to tighten and loosen the screw on the right side (drive side), use a left-hand screwdriver and turn it counterclockwise.

Right-handed threading is used on both the left and right sides of the Italian. Both the clockwise and counterclockwise sides tighten and loosen. It is common for Italian threaded cups to be marked “36×24.”

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Remove both of the cranks to get started.

Look for tool fittings in the threaded cups. It’s possible to choose from a variety of designs and tools. See the Bottom Bracket Tool Set: In order to choose the suitable tool, threaded and threaded together

When finished inserting the tool, spin the non-drive (left-side) cup counterclockwise while securely gripping the tool. Discard any internal sleeve that may have been present. Take note of any spacers that may be under the cup while putting it back together.

Remove the drive (right-side) cup by rotating it clockwise to dislodge it from the vehicle.

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Start by preparing the thread. If you buy a new cup, it may already have dry threadlocker on it. Install these as soon as you receive them.

Park Tool ASC-1 anti-seize is an alternative. Corrosion is prevented because of the long-lasting barrier that is created in the threaded junction.

Threadlockers like the Park Tool TLR-1 are still another choice. The lubrication provided by the liquid compound will aid in the tightening process before the compound hardens and seals the cup in place.

On the right-side cup, install any spacers that are necessary. The right side should be threaded into the shell counterclockwise. Tighten the cup to the manufacturer’s recommended torque setting. 25 to 30Nm are typical values for a typical application.

Turn the left-side cup clockwise to install and tighten.

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