Ad
related to: installing press fit bottom bracket
Search results
Results from the WOW.Com Content Network
The bottom bracket is pressed directly into the frame. Using pressed in standards allows frame manufacturers greater flexibility in the frame design, and can offer greater stiffness and reduced mass. A disadvantage is that assembly and disassembly of press-fit bottom bracket bearings require expensive special equipment.
Press fit is achieved with presses that can press the parts together with very large amounts of force. The presses are generally hydraulic , although small hand-operated presses (such as arbor presses ) may operate by means of the mechanical advantage supplied by a jackscrew or by a gear reduction driving a rack and pinion .
The bottom bracket shell is a short and large diameter tube, relative to the other tubes in the frame, that runs side to side and holds the bottom bracket. It is usually threaded, often left-hand threaded on the right (drive) side of the bike to prevent loosening by fretting induced precession , and right-hand threaded on the left (non-drive) side.
Engineering fits are generally used as part of geometric dimensioning and tolerancing when a part or assembly is designed. In engineering terms, the "fit" is the clearance between two mating parts, and the size of this clearance determines whether the parts can, at one end of the spectrum, move or rotate independently from each other or, at the other end, are temporarily or permanently joined.
Bottom pull: Commonly used on road and touring bikes, this type of derailleur is actuated by a cable pulling downwards. The cable is often routed across the top or along the bottom of the bottom bracket shell on a cable guide, which redirects the cable up the lower edge of the frame's down tube. Full-suspension mountain bikes often have bottom ...
Shrink-fitting is a technique in which an interference fit is achieved by a relative size change after assembly. This is usually achieved by heating or cooling one component before assembly and allowing it to return to the ambient temperature after assembly, employing the phenomenon of thermal expansion to make a joint.
The bolster plate is mounted on top of the press bed and is a large block of metal upon which the bottom portion of a die is clamped; the bolster plate is stationary. Large presses (like the ones used in the automotive industry) may be equipped with die cushions integrated in the bolster plate to apply blank holder or counter draw forces.
Push-to-pull, push-to-connect, push-in, push-fit, or instant fittings are a type of easily removed compression fitting or quick connect fitting that allows an air (or water) line to be attached, nominally without the use of tools (a tool is still usually required for cutting tubing to length and removal).
Ad
related to: installing press fit bottom bracket