there different types of bears but sorry i honestly don't know why except THERE DIFFERENT TYPES OF BEARS
There are many, many different types of bearing, Which one you use is dependent on what you wish to use it for. You should look them upin a "bearing" catalogue
Just one mm is all the difference there is.
Floating bearings can move on the shaft fixed bearings cannot. If you search on Youtube for 'floating bearing animation' there is a short video showing the difference.
Pivot bearings are frictionless bearings and suitable for pivotal, angular, or oscillating applications. Collar bearings are often used install equipment with a simple set screw.
Spherical bearings are round (ball bearings) while cylindrical bearings are in the shape of elongated rods.
the newer cars have sealed wheel bearings already in a bolt on hub assembly, some even come with abs sensors installed.the older cars had roller bearings & races that needed packed & adjusted. they both are wheel bearings.
Front or rear makes a big difference, need to know.
For the most part yes. Get the cheapest quality bearings like milehighskate bearings (founs on milehighskates.com) or mini logo. It will ride just like expensive bearings. Abec doesn't make a difference in skateboarding.
On your 99 fatboy you have timken tapered wheel bearings on the 01 fatboy you have sealed wheel bearings that aren't interchangeable. Timken does however make a cross reference replacement for the sealed wheel bearings. Due to the bearings having different axle bolt diameters
A few types of bearings are plain bearings, jewel bearings, and fluid bearings.
Wheel bearings, main bearings, connecting rod bearings, cam bearings, axle bearings, carrier bearings, pinion bearings and so on, need to be more specific.
2 wheel drive or 4 wheel drive? It makes a difference.
i believe bone Swiss 7's are better because bone Swiss is known for their competition grade bearings. but if both bearings are rates 7 then there should be not much of notable difference.