This question is a bit unclear, it doesn't tell if you're:
A) just talking about the crank arm,
or:
B) if you want the chain to go on the left side
If it's A, then it depends on which type of bottom bracket you've got, it's different if it's cottered, square taper, splined, or BMX style. Cottered cranks use wedges to hold them on, square taper use bolts that go into the BB axle. Splined can use either a square taper style axial screw or a pinch bolt. BMX tends to use pinch bolts. Then there are cranks where the left crank arm is permanently bonded to the bb axle
if it's B, it's not really advisable to use a right sided crank on the left side of the bike. There's something called precession, which tends to cause the pedal to come off.
Left side cranks use a counter-clockwise pedal thread to avoid the problem.
A 3-piece BMX crank set typically consists of three separate components: two crank arms and a spindle. The key features of a 3-piece BMX crank set include durability, strength, and compatibility with various bottom bracket sizes. Benefits of a 3-piece BMX crank set include improved power transfer, easier maintenance, and the ability to customize the crank length for optimal performance.
A crank (or a crankset) is the thing that sits in the middle of the bicycle, has the chain on it and have the pedals attached to it.
No, only the one that was made for it.
You measure it. A ruler and a caliper are useful.
When choosing a BMX crank arm for optimal performance and durability, key factors to consider include material quality, length, weight, stiffness, and compatibility with your BMX bike's bottom bracket.
Yes you can, but take it to a bike shop or someone who knows what they are doing
It depends if you have a 3 piece crank, spokes, brakes.
By crank do you mean sproket? The smallest iv seen is a 22t but there may be smaller, or do you mean 3pc cranks?
The only thing on a BMX regularly called a spindle would be the crank axle. Although I suppose one could use spindle for the pedals and the wheel axles as well.
Usually not. It'll be fast at the start, but a small crank will limit top speed unless you can turn the pedals really fast.
Where ever he put it last.
A BMX 3 piece crank conversion kit offers improved durability, strength, and performance compared to traditional one-piece cranks. The installation process involves removing the old crankset, installing the new bottom bracket, attaching the new crank arms, and adjusting the chainline and tension.