becoming increasingly important to use a
torque wrench when working on your bike
particularly there's more and more
superlight carbon and alloy parts get
introduced onto the bikes that we ride
gone are the days and you just used to
be able to lean on a bolt to tighten it
up so why is it important well over
timing or under tightening your bolts
can be really dangerous under timing we
can clearly see why because it's
sensitive that's just stuff coming loose
but over tightening can be just as bad
for example if you over tighten your
stem bolts up here apparently that's the
biggest cause for carbon handlebar
failure so you can clearly see that it
is really really important but
furthermore if you over tighten the bolt
and you do break something that part is
then going to be outside the
manufacturers warranty and all
likelihood so it's going to be a costly
mistake to make so you need a torque
wrench clearly but how do you use one
well if you have a look around your bike
you'll see loads of little numbers all
over it followed by either the letters
nm which stands for Newton meters or
pounds per foot
so they refer to generally the maximum
recommended torque although you probably
should check either in the manual that
came with the component or indeed just
online to find out whether it is the
maximum torque or the recommended talk
generally if it's the maximum torque you
should then reduce that figure by about
15 to 20 percent so in the case of our
stem bolt up here as five Newton meters
so on my torque wrench I'll set it to
four which is obviously 20% less than by
now it's important that you hold your
torque wrench in the right place it's
pretty clear you just hold it on the
handle don't hold it up here because
you've effectively choked the torque
wrench and it won't work properly and
then when it gets the recommended talk
they go that's it
it's as simple as that well it's just
not quite as simple as that
now when you finish using your torque
wrench you should always back it off to
virtually zero not completely zero but
pretty much and that means that it stays
calibrated for longer now there are a
few different types of torque wrenches
on the market this is an example of one
that's quite high-end
it's got an internal clutch mechanism
which we've just seen it in action and
then obviously the dial there it's also
a slightly cheaper but just as effective
Eyebeam torque wrench where you have to
be a little bit more careful it won't
tell you when you get to the right talk
you have to actually look at it on there
but again it works brilliantly and then
now I see because of the sheer
importance of torque wrenches a lot of
manufacturers are also supplying them
with bikes so this one here as she comes
with a trek bike it's set just to five
Newton meters so that when you're
tightening up I think in this case it's
the C clamp that you don't over tighten
it and it works in exactly the same way
as the other one okay job done it's
worth mentioning that to avoid
recalibrating your torque wrench too
much and don't use it to loosen bolts
just use it to time it's a small thing
but might make a difference so there's
our torque wrench basics but to use it
really accurately we also need to pay
close attention on how we prepare the
bolts and also the clamping surfaces now
when you are preparing bolts there's
three main ways you'll do it you can
either grease the thread or you can put
a thread locking compound on the thread
or it goes in dry now this is really
important grease or thread lock both
effectively lubricate the bolt which
transfers more torque to the clamp as
less energy is lost as friction so you
need to pay close attention to the
manufacturers recommendations as to
whether they say that you put the bolt
in lubricated or dry effectively if you
talk a bolt that's lubricated up to the
dry specifications you're just going to
be over tightening it which is yet
another reason why you don't talk
anything to them recommended maximum
settings because you give that little
bit of leeway
the other thing is to pay attention to
the surfaces that you're clamping if for
example it's handlebar or a seat post
you want to apply it fiber grip which is
a slightly abrasive paste that
effectively increases the friction
between the surfaces that you're
clamping what that means therefore is
that it's less likely to slip
particularly key with handlebars and
seat posts and therefore you don't need
to overtalk the bolt in order to prevent
it moving now some of you will say you
should put fiber group on any of these
parts we say only if they're either both
carbon or ones alloy on one's carbon and
that's in line with most manufacturers
that we spoke to one place you shouldn't
use fiber grip so we're told is on the
steerer tube there use it too much and
over time you'll actually damage the
steerer so stay safe or pay attention
that to the torque specs on your bike
and use a torque wrench then it's just a
case of paying attention it to the
preparation of your bolts and also the
clamping surfaces to make sure the
torque specification is accurate and
also you don't get any slippage worth
bearing in mind all indexing is done
using that barrel adjuster there so once
the limit screws are set we leave them
be so everything now is just going to be
here okay so we