wightstraker said:I have two questions for you all: First, how hard would it be to
convert a 12 speed road bike to a fixed gear?
Trivial.
Quoted message said:I'd do the work myself,
but would the parts be expensive?
It can be done on the cheap, for the price of a sprocket ($15) and a
chain ($10). That requires you to:
1) remove dérailleurs, cable, shifters.
2) remove chainrings, and put the bigger one where the smaller one was,
on the inside of the spider. You may want to get shorter chainring
bolts, or jerry-rig a few washers to space it out.
3) Remove the freewheel (as it's a 6-speed rear, I presume it's a
freewheel), and put the sprocket on. It will tighten when you start to
ride, but be careful not to apply back-pressure on the pedals until you
have some miles on it, preferably including some hills.
You may have trouble with the chainline. Ideally, the plane of the
chainring should be the same as that determined by the sprocket. The
sprocket may be offset by a couple millimeters without trouble, but more
than that could make it prone to dropping a chain, which is bad. If the
sprocket is very much too far in (this is likely), you can try
a) putting a spacer in between the sprocket and the hub. Some cassette
spacers work well, but get a metal one if you can.
b) re-centering the hub on the axle. If you look, there is a big spacer
on the right side of the axle that pushes the hub to the left, to make
room for the freewheel. Take that off, and get two about half the size,
and put one on either side. Sometimes you're lucky and the spacer is
actually several pieces. Juggle them around until the chainline is
right. Then, you have to re-dish the wheel to keep the centerline of
the rim midway between the dropouts.
Quoted message said:Second, what would be the best gear
ratio for my bike? I mostly use it to get to around town - nothing too
strenuous; the terrain is relatively flat, but I like to move
quickly.
Pay attention to the gear you like to use most for this sort of riding
when on your geared bike. Figure the ratio, and match it as closely as
you can. Be willing to shell out for extra sprockets, to be able to
change gears to accommodate your conditioning, road conditions, and
rides. I have every size from a 12 to a 21. I haven't used the 12, it
was given to me as a joke. But I have ridden with all the others, for
one reason or another.
--
David L. Johnson
"Business!" cried the Ghost. "Mankind was my business. The common
welfare was my business; charity, mercy, forbearance, and
benevolence, were, all, my business. The dealings of my trade were but
a drop of water in the comprehensive ocean of my business!" --Dickens,
