Just like electrical wire, the lower the #, the thicker the wire.
Spoke technology has come a long way. For all intended purposes,
when buying spokes you're pretty much gonna deal with 10 thru 17
gauge spokes. Theres bladed spokes, double butted (thick at the ends
and thin in the middle), straight gauge (same thickes throughout),
carbon fiber & straight pull (they don't have the j-bend at the end
for use with special hubs. There's just as many variations on the nipples
as well, length, brass, aluminum alloy, hex head, splined, self securing.
For those special conversions there's also spoke washers and nipple washers.
Spoke washers for using smaller gauge spokes in large holed hubs, and nipple
washers for helping seat the nipples in the inside curve of some rims.
For most BMX applications your gonna stick with straight gauge 10,12 or 14
gauge in varying lengths. Older really heavy, heavy duty rims will use the
super thick 10 almost like motorcycle spokes. Most heavy duty rims, like older
Schwinn Cruisers will probably use the thick 12 gauge. The majority of rims
on most 20" BMX will most likely use 14 gauge.
If you're building a wheel and you have some spokes that are too short,
sometimes you can make them work by using longer nipples. You can also
make your spokes longer by reducing the number of times that you cross them.
If you do a 2x then the spokes will be shortest, if you do a 3x (most common)
it will require a longer spoke, and 4x will require the longest spoke.
So, if you are lacing up a rim two cross (not very common) and the spokes poke
through the rim a lot, you could try lacing it up three cross, then you would see
that the spokes don't poke through the rim as much. If you have built up a
wheel and you are happy with it, but the spokes poke through the nipple head
way too much, so much so they could pierce the tube, you would use a
spoke nipper, a special cutter that cuts the end of the spokes after
the wheel is laced. Sometimes this requires finishing as it may still leave
a sharpened edge, so you would need to file, or dremel them down with a grinding
bit. This is fine too, but makes it almost impossible to dissasemble and
reuse the spokes in the future. Using used spokes!? Not recommended, but
this hobbies about scrounging! We're not Nasa here, so go ahead and reuse
anything you can.
Spoke length? Are you building for light weight or strength? A radial laced
wheel will have the shortest spoke length possible and the shortest nipple
all to reduce weight, but will not be as strong. A 4x laced wheel will
be super strong, but will have more material and be heavier. Want a heavy
duty strong wheel, but not super heavy duty? Then try a thinner gauge spoke.
Depends really on your application. So you have some cool spokes from a 26"
and you want to use them on your 24" or 20" wheel? No problem. No need to
cut and rethread, you can wrap or twist them around each other. Not very
conventional, but produces a cool effect. If there's a will, there's a way.
Spokes too thick? No problem, drill out the holes in the hub flange or
drill out the holes in the rim. Remember, it's only NOS once.
So finally, get yourself a spoke ruler.
It has inches and mm for those
quick length conversions and a diameter checker. Learn to use it correctly.
This tool is less than $10 and invaluable! For the beginner or pro.
Makes rebuilding a breeze. If you're simply relacing with new spokes all
you need do is pull one spoke and measure length. Then reorder new spokes.
Really speeds things up if your replacing, you only need one spoke intact,
then you can just snip the rest and you've dissasembled your wheel in
60 seconds! Beware of snipping, those suckers can fly when cut under tension.
Also, if you're using different hub/rim combos when rebuilding, it may
require a different length. Uh, oh.. ordered the wrong length? See above,
modify build with longer or shorter nipples, lace using a different cross
pattern, try a different hub with bigger or smaller flanges, wrap or twist
the spokes, cut and rethread, or nip the end after building and dress the end.