I am very much interested in single speed (not sure about fixed gear though). I test rode a Langster today and it was quite what I expected (gearing is a little tall IMO). I am planning to build one using IRO frame and here are my questions:

1) I am planning to use a mtb style flat bar, and is there a brake lever out there that works well with sidepull brakes? I read somewhere that mtb levers have a unsuitable leverage for a sidepull brake. If so, what are the options.

2) Is it possible to use the rear wheel from a geared bike (with QR) on a horizontal dropout frame? I am thinking that a surly tuggnut type device will hold the hub in place. The only issue is if Jamie roy has 130mm spacing between rear dropouts (any IRO owners?).

3) what is the popular gearing option? I live in boston/cambridge area, not too flat, more like 'rolling hills' type of landscape. The Langster I tried today had 48x16, and I felt it was a little too tall.

comments/openions appreciated.

I am very much interested in single speed (not sure about fixed gear though). I test rode a Langster today and it was quite what I expected (gearing is a little tall IMO). I am planning to build one using IRO frame and here are my questions:

1) I am planning to use a mtb style flat bar, and is there a brake lever out there that works well with sidepull brakes? I read somewhere that mtb levers have a unsuitable leverage for a sidepull brake. If so, what are the options.

2) Is it possible to use the rear wheel from a geared bike (with QR) on a horizontal dropout frame? I am thinking that a surly tuggnut type device will hold the hub in place. The only issue is if Jamie roy has 130mm spacing between rear dropouts (any IRO owners?).

3) what is the popular gearing option? I live in boston/cambridge area, not too flat, more like 'rolling hills' type of landscape. The Langster I tried today had 48x16, and I felt it was a little too tall.

comments/openions appreciated.

Some answers

1. There are mountain style brake levers that will work with road brakes. I seen it many times but I'm not sure who makes them.

2. If your riding single speed, a standard rear wheel w/ a quick release works great.
A) A 8-9 speed gear hub with 1 cog and a lot of spacers is a better setup than a BMX
style freewheel. It allows you to set a perfect chainline. Also, a rear road hub will
last longer than a BMX freewheel. The down side is fixed gear is not possible without
major modifications.
B) I use a quick release on two single speeds with no problems at all. My only
suggestion is to use a metal not plastic QR. Most Shimano QR are metal and have
good "teeth" to bite the dropout
C) I use 42 x 16 and 45 x 17 on my SS's. They both give you close to 70 gear inches
It's a good place to start.

Any mtb lever will work. Newer levers designed for use with an inline (V style) brake pull more cable, but will work just fine. Shimano sells a lever they call a "flat bar road lever", wich is really just an Alivio cantilever brake lever renamed. I like Snafu and Paul levers for their CNC appeal, but Tektro levers can be had very cheaply. Most shops will have one or two kicking around reasonably cheaply. I'm a big fan of metal levers. The LX level from Shimano is adjustable in reach and pull. Very nice mid priced lever with a lot of adjustment.

I use a 40X16 or 42X16 with a fixed gear, but I'm old. If I wanted a freewheel, I would probably go a little lower to climb easier.
A quick release work fine with freewheel single speeds. most road bikes had QR and horizontal dropouts before STI became standard. You should get a good Campy or Shimano steel skewer. Most other modern skewers are not strong enough to hold a wheel in a horzontal dropout. I use a QR with the fixed gear, but the wheel gets misaligned when my pedlaing gets jerky at high RPMs. I anchor the axle with a couple of zip-ties on the right side, which helps, but a proper solid axle would be better.