113
112
example of this might be an alloy cassette
which offers a huge weight saving, but comes
at a high cost and won’t last long at all. The
plus side though, is that if it is already a part
that you replace regularly, you can justify
the upgrade cost as dollar difference, i.e.,
the difference in price between existing
and proposed, instead of simply the cost of
the proposed part, because you would have
bought a new one soon anyway.
Another idea here might be to have
special lightweight gear that you save for
big races. This is a good idea but remember:
when you have the durable parts back on for
a training ride with your mates, no one will be
impressed when they pick up your bike.
Chances are you’ve put yourself on some
sort of diet over the years but what about
your bike? Few too many love handles? Read
on for The Biggest Loser – Mountain Bikes
Words by Andrew Blair
GET FAST
A
fter years of snubbing ‘weight
weenies’ I decided, after much
deliberation, that I would switch to
the dark side and look at shaving a few grams
off my bike for myself. As if to justify my
switch, I decided that I wasn’t going to get
too obsessed about it. My goal was to shave
weight while being mindful of money and the
performance/weight compromise.
Rather than just loading up on credit
card debt and ordering all the most expensive and lightweight parts available, I thought
it best to do a bit of research and try to
come up with more economically sensible
approach. After a bit of research and careful
parts replacement I managed to take about
500g off an already sub-10kg hardtail!
Before I go too far it is worth mentioning
that bike weight isn’t everything. Relatively
speaking, the weight of your entire bike is
probably only about 10% of the total weight
you have to propel up a hill, or out of a corner
(which of course includes your body weight),
and the potential savings that you could make
are generally only around 1%. But remember,
every gram counts.
Just about any bike could shed a few
grams. It simply comes down to balancing
cost, reliability and performance. Of course
there is no point reducing the weight of your
bike if it negatively affects performance. For
example, anyone can go out and buy super
light tyres with very little tread to knock
half a kilo off their bike for less than $200
(40cents per gram – cheap!), but not many
people would be able to ride that bike fast
without flatting all the time.
With all of this in mind, there are still
plenty of possibilities for weight reduction that don’t comprise performance. To
establish this I’ve employed a simple method
to get the best value. Taking off huge chunks
of weight is not easy (and is generally very
expensive), so it’s a matter of looking at
every little component on the bike. Every
gram counts here so be sure to spread your
scope wide enough to capture every part you
can think of. Basically, you should list every
component with potential to be replaced,
work out the weight saving and the cost of
each, prioritise them in order of $/gram, and
then spend up to your budget on the parts
that will maximise the reduction in grams.
Simple! Read on for my step-by-step weight
loss regime.
Step 1 – what sort of bike do you want?
Start by defining some of the parameters
that will affect your decision making, this includes: purpose of the bike, riding style, rider
weight, and typical trails. If you weigh 100kgs
and love to get a bit loose down rocky trails,
then you will make different choices to that
of a 50kg elite female XC racer. It is important to keep these things in mind throughout
the process in order to stay on track and
ensure you don’t end up with a bike which is a
compromise for your intended purpose.
For me this included:
(i) Rider weight – I weigh 73kgs. This is
probably medium weight for a cross country
rider, but is getting close to the weight limits
of some lightweight parts.
(ii) Riding style – I’d like to think I was
smooth but I do have a history of breaking
things, so I’ll say my riding style is aggressive.
(iii) Intended purpose – My primary focus
is cross country racing so I need parts that
will withstand regular bouts of around two
hours of abuse as well as long training day
epics of up to six hours.
(iv) Typical trails – I live in Cooma near
the Snowy Mountains in NSW which is super
rocky and raw. I often ride the trails built by
the little DH bandits in town that are getting
up towards the limit of my bike and my skills.
Step 2 – the bike once-over
From here, brainstorm all the parts on
your bike that could possibly be exchanged
for something lighter. It is very important
to look at a very macro level, e.g., don’t think
of your rear derailleur as a single component, instead, think of it at the nut and bolt
level. I can guarantee that you will not think
of everything the first time, so chat to your
mates or your bike shop to get some more
ideas. Don’t bother including your mud guard
or mud tyres, because the day you put them
on for a race, all of this stuff goes out the
window. An example of this was after a recent muddy race a friend of mine weighed his
bike (normally 10kgs). It weighed over 30kgs!
On this occasion, you couldn’t even see most
of the components, let alone feel the weight
of them.
This step is also a good time to think of
any parts that have a history of poor reliability in the context of your intended purpose.
For example, if you puncture often, then
perhaps think of running slightly heavier but
more durable tyres. Of course this is a backwards step in terms of the weight reduction
exercise, but if it helps you to get to the
finish of a ride hassle-free then it is definitely
a good thing.
Step 3 – categorising the components
Now, split the list into three groups being
mindful that there are grey areas here and
it’s up to you to decide what goes where.
(i) Fixed: identify the parts that you don’t
want to change, I’m assuming that you have
a frame that you like, otherwise you would
be looking at a new bike, so lock in the frame.
Things like this are also big ticket items and
for me they were outside the budget of this
exercise. Other things that might make this
category are forks and wheels.
(ii) Baseline: this group is made up of
parts that don’t wear out quickly, if at all,
and that don’t compromise performance
or durability. Here I am talking about bolts,
seat post, seat collar, quick release skewers
and jockey wheels. Most importantly this list
must include all the superfluous parts that
aren’t necessary like that excess bit of fork
steerer or seatpost, and getting rid of the
granny gear or fork lockout if you never use
them. This type of weight saving is like gold!
Each saving might be small, but the savings
are generally cheap (or free) and will directly
subtract weight from your baseline.
(iii) Consumables: this includes things like
tyres, chains and cassettes. They can have
plenty of potential for weight savings, but
they wear out, so keep in mind that these
could have an on-going cost associated with
the weight loss in addition to the upfront
cost if the new part wears more rapidly. An
Step 4 – the spreadsheet
Now it’s time to put it all in a spreadsheet.
Column One
Type all your ideas for baseline parts and
consumables into a column of a spreadsheet.
Column Two
Come up with the possible replacement
part and type it into the next column. Remember to be realistic here. Lightweight isn’t
always good. Some light weight parts compromise too much when it comes to durability,
so go back to your defined parameters and
remember that this is a mountain bike not a
roady. Ask your mates or your friendly bikeshop guy for their experience with anything
super light that you are concerned about and
be especially wary of light parts that are also
cheap. There is a saying that says out of light,
cheap and durable, you can only choose two.
It is also important here to consider the
three groups from step 3 and the implication
of relative wear rates. A trap that you can fall
into when replacing a baseline part is that a
poor choice can move it into the consumable
category, which can become expensive. I made
this mistake with pedals, when I decided to
ditch a reliable older model for the super light
jobs. I was lured in by the massive 120g weight
saving, but the new pedals lasted about 4
weeks before the bearings were shot. If you
can’t come up with a suitably durable part
then leave it blank.
Column Three
Record the weight of the existing part
in the third column. Getting a good set of
scales is great for this, otherwise you will
have to resort to “claimed weights”. This
can be a bit dodgy; the best way is to weigh
real parts. Also remember that worn parts
weigh less than new ones so make sure you
compare apples with apples. With things like
excess seat pole and fork steerer it is tricky
to estimate the weight, so guess for now, but
when you cut them down throw the off-cut
on the scales and record the saving.
Column Four
Now, record the weight of the proposed
part in the fourth column. The internet is
a handy tool here but, again, be careful of
claimed weights. Your local bike shop has the
big advantage of being able to weigh the actual item to be sure you are getting what you
expect. Another little trick here is to weigh
many of the items in question and take the
lightest one, since most production processes result in slight variation between individual
items. In this way you might get a few extra
grams for free. A friend of mine, who loves
counting grams recently asked an importer
to weigh all of the handlebars they had in the
warehouse so that they could send him the
lightest one. This is a bit extreme. I guess it
comes down to how thorough (or annoying)
you want to be.
Column Five:
Research the cost of the replacement
part and record it in the next column
Column Six
In this final column calculate, the $/gram
for each part by dividing the cost by the
weight in grams.
Step 5 – getting sorted
Sort the list in order of $/gram. Everyone’s list will look quite different because
it depends on what original parts you have,
what new parts you have found and what they
blairy’s weight saving chart
dollar$
ENDURO 12
ENDURO 12
grams saved
cost. My list started with a few at the top for
$0/gram, like removing the fork lock-out, down
through to $2/gram for light rotors and quick
release skewers, $4/gram for titanium bolts,
and about $10/gram for carbon bidon cages.
If you plot the savings on a graph it’ll look
something like what you see below.
You can see now exactly where you need
to focus your spending. With mine I could get
over 200g for free, not a bad start! It’s just
a matter of working your way down the list
until you get to the limit of you budget. You
will also notice that the more weight you
shed, the more expensive it is to keep going.
You should also keep asking yourself if any of
the proposed parts will be an unacceptable
comprise.
Step 6 – go shopping!
Make a shopping list and go and buy the
new parts.
You should have been able to get rid of
some significant weight from your bike, but be
careful not to obsess about it too much. It can
easily get expensive and you can end up with a
bike that compromises your performance.
Finally, in the words of Lance, it’s not
all about the bike…
In a racing context, think of everything, not just the bits on your bike. Just as
important are your shoes, spare tube, gas
cartridge, helmet and bidons – although I’m
not suggesting you race without water.
Be careful with internet forums like Weight
Weenies. Most of those guys seem to be so
proud of their bikes that, in a real world scenario, wouldn’t last a section of single track
Good luck.
Blairy’s packed up his lightweight beast
and shipped it – and himself – to Europe
in ‘09 to race against the world’s best. You can
follow his progress on his website:
www.andysracingblog.blogspot.com