alright, lets start with the frame:

this pic should sum it up.

^the holes you see in the headtube are for removable gyro tabs.

frames can also have cutouts.these are cutouts


next, we move to the materials used in bmx:

Hi-ten: used on lower end bikes. heavy, and weak. rusts.
chromoly(chromo): the best for bars, forks, frames, and also good for cranks, spindles, axles. light and strong. rusts.
aluminum: weak, but very light. usually used for stems, seatposts/clamps, rims, pedles, and bmx-racing frames.
titanium: stronger than aluminum, weaker than chromo, lighter than chromo, heavier than aluminum. usually used for spindles, axles, and bolts.
magnesium: usually only seen on pedles. light.
plastic/composite: weak, light, sometimes used on pedles, and pegs.

next, wheels:

a wheel consists of-

rim-

available in single, double, or triple walled. single is the weakest, and triple is the strongest.
available in 36, or 48 hole.

spokes/nipples-

top left is spokes, bottom right is nipples.

hubs-
cassete:

available idown to 8 tooth-newer technology
freewheel:

available down to 13 tooth
freecoaster:
ability to fakie with out peadling back. look similar to cassete hubs


hubs come in sealed, or unsealed bearings.
also come with a 3/8ths or 14 mm axle(14 mm is stronger, bigger and reccomended for grinding)
some axles are hollow to reduce weight.


next up, bottom brackets


american-origonal, biggest, uses bearings that sit in cups. cups press into frame
mid-same size bearings as american, but the bearings press directly into the frame, no cups needed
spanish-smaller bearings than mid/american, bearings press directly into frame
european-bearings sit in cups, which thread into the frame

next up, headsets

integrated-bearings sit in cups that are molded into the frame


regular-bearings sit in cups which press into frame


and now, brakes

u-brakes- found on street, dirt, and flatland bikes


v-brakes-found on racing bikes


gyro- allows bars to spin without tangleing cables


gyros require special cables.
ubrakes and vbrakes use different types of levers.


and, tires

street/park/flatland- not knobby like dirt tires, higher psi(80-120) made to take more abuse than dirt tires

dirt-usually 60 psi, made specificly for better grip on dirt


forks

usually chromoly. come with 14mm or 3/8" dropouts.


bars:
2 piece

4 piece

1 piece




the most common types of bars are 2 piece. they consist of a solid piece of tubing and a crossbar welded in. there are also 4-piece bars, and 1 piece bars. 1 piece is most commonly seen on the tracks.

im sure i forgot something, so this will be edited soon (mostlikeley)
ideas, questions, comments, post it up here.

Page 1/1
This article has been read 8908 times

Comments

Publish your own Article