There's another thread on how I'm going to take a run at a <9kg Gallop
build. I've started this thread to lay out exactly how I plan out all the
builds in my workshop. I'll apologize in advance for the long narrative,
but hopefully the few of you who poke around on Thanksgiving Day are
looking for something to read...
My freshman year of high school, in the Fall of 1983 (Troy High School,
Fullerton, CA) I took a typing class as an elective. It made perfect sense
to me as preparation for taking a computer elective the following semester,
ha ha. We had a project in typing class to type up a formatted outline,
following all the rules of categorization with the indents and headings
just so. Each student had to come up with their own content for the
project and type it up. In the Fall of 1983 I was a habitual cover to
cover reader of Bicycling and Winning! magazines. I was obsessed with a
Bruce Gordon Chinook in one of those magazines, and I used the build list
for that bike as the content for my typing project. From that moment
forward, every build fits into the same framework. Every build is
comprised of five categories:
1. Frame set
2. Wheels
3. Drivetrain
4. Components
5. Accessories
I throw every build into a spreadsheet in those five groups. It serves to
organize my thoughts for every build, and as a checklist before a build
begins, and sometimes helps me pull the build together mentally to
anticipate the places where a nuanced build might have places where I could
paint myself into a corner. Sometimes, but not always, I'll use columns
for each line to list the weight and/or the price of the stuff I'm pulling
together. By filling out that spreadsheet exhaustively with best guesses I
can get into the ballpark on total price or total weight as a preview. As
guesses become certainties, the numbers come into focus. As I've gotten
older, most of my builds have targets that have nothing to do with price or
with weight: they are more about how exactly I want to experience cycling
on that particular machine. The term I use to capture that relationship
between the build and its target is the "build concept".
So, let's start running through the build for my Gallop: Section 1 is the
Frame Set, which has three main parts
1. Frame set
A. Frame
B. Fork
C. Headset
When I get my frame set, I'll remove the fork and weigh the fork with the
fork crown. I'll pop out the headset cups and weigh the headset minus the
fork crown. I'll remove the pre-installed bottom bracket and weigh the
bare frame. Then I will remove every bolt that is screwed into the frame
and weigh that collection of bolts separately and re-weigh the completely
stripped down frame.
The Riv page for the FSA Headset claims it weighs 93.8 grams. That's very
light. 100g is the typical placeholder for a headset when I'm planning
something out. Over 100g and I could substitute something lighter. Under
100g is pretty good. If it's really ~94g I'm keeping it.
The bolts gives the opportunity to do some gram-chasing. Big picture,
bolts are always steel, there are ways to make those steel bolts lighter.
They are:
1. Air is weightless. Can you live without that bolt? If so, consider
leaving it out. That's free and totally weightless
2. Plastic is almost as light as air, and is very cheap. Plastic metric
bolts in all sizes are made. They weigh almost nothing and cost very
little. If you don't need to bolt anything to that threaded hole, but want
to plug the hole, consider plastic and screw it in with just your fingers.
3. Aluminum is 1/3 the weight of steel. Virtually every high end mountain
bike has aluminum water bottle bolts. They break sometimes, but 19 out of
20 times they break, it was because the person holding the wrench over
tightened them. For low-stress bolt on applications, aluminum is great.
They are not free, but if you buy them in bulk, the per-bolt cost is not
that much. If you bought them a while ago and they are just there on the
shelf, it feels like they are free.
4. Titanium is half the weight of steel and nearly as strong. Pretty much
anything steel on a bike could be done in Titanium. It's a bit lighter and
is really expensive.
5. Shorter steel bolts are lighter than longer steel bolts. Sometimes
water bottle bolts are 16mm long when 10mm bolts still have 100%
engagement. Swap 'em out if you have them laying about.
A gram or two doesn't make any difference but if you look for a gram or two
everywhere, they can add up. You eat the elephant one bite at a time.
The last consideration in this first chapter will be steer tube length. If
the final build has me slamming my stem, then that will signal that I don't
need that much steer tube. Typically Rivs come with ~30mm of headset
spacers. If I can pull the spacers and cut the steer tube down 30mm,
that's more free grams. 1" steer tubes weight almost exactly 1g/mm. If I
want to keep the extra stack of the long steerer and spacers, then I'll
keep it.
That's section 1 of my upcoming build. Section 2 is wheels, and that's the
only section that is 100% complete right now. I'll get into that later...
Bill Lindsay
El Cerrito, CA
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