Technical how-to's: Using a chain-breaker without breaking the chain
For cleaning, maintenance, tuning and adjusting, it is often necessary
to mount and unmount the chain from or to the kart. Many racers these
days use chains without a master link, i.e. a special link used
to open the chain. Instead, all the links of the chain are the same.
The advantage is that there is no one weak link in the chain and that
length adjustments of the chain are easily possible.
So how can such a chain be opened at all? The key is, as usual, the right
tool. In this case the tool is a chain breaker, a very fitting
name. The tool really allows you to open a chain quickly and efficiently,
to add new links or remove a few links to modify the chain length, etc.
But if not used properly, you can seriously ruin some of your chain links,
which is utterly annoying if you are in a hurry because your next race
starts in a few minutes, and you just quickly wanted to change the gear
ratio and now you are sitting there with a screwed up chain while they are
calling your class already to the grid... Been there, done that.
To avoid this, it is necessary to use the chain breaker properly. It's
not difficult to do and a few simple things to consider will make the
whole experience much more enjoyable for you and your chain.
How does a chain breaker work?
Its's typically a small block of machined
metal with a precicely shaped 'groove' across it's surface in which a
couple of links of your chain will exactly match. From the side then
there are two screws penetrating into the block of metal. By screwing
the screws inward (usually with an allen wrench), their ends will poke
into the groove area. One of the screws has a thin end, almost the same
as the rollers (the round little metal pins which connect the links) of
your chain, while the other screw has a flat end. You use the screw with
the thin end to press a roller out of its link, thereby breaking the
connection of the chain at that point. Once it is time to connect the
chain back together again, you use the flat-ended screw from the other side
to press the roller back into the link. It's that easy.
All of this works really well and allows you to break or connect a chain
in just minutes. But things can also easily go wrong! When you try to
push out a roller, it is possile to bend the side walls of a link with the
thin end of the screw. When you try to connect the chain again, the same
is possible when the roller is not properly aligned with the hole in the
wall of the link. Once a side wall of the link is bent, it's unusable
and you will have to replace it. That can get time consuming.
Breaking the chain
So to break the chain, use the following precaution: While screwing in
the screw with the pointy end, only turn half a turn after its end made
contact with the roller. Then go back a quarter turn. By letting off
the pressure you will ensure that screw-end and roller have time to align.
Be particularly careful at the beginning, when the screw-end needs to find
the hole in the link side-wall. Then go another half turn and let off
a quarter turn. Continue this until the screw-end has cleared the
side-walls of the links and pokes out into the middle of the chain. You
can then continue more quickly. Press the roller out all the way towards
the opposite link side-wall, being more careful towards the end again.
BTW, make sure you don't press out the roller too far, or it will just pop
out of the chain on the other end. It's easy to loose the rollers and
very difficult to get them back into the link. So just press it out far
enough so that it clears the inner link's side-wall, but still sticks in
the wall of the outer link.
Connecting the chain
When it is time to connect the chain again, one must be even more careful.
After placing the two chain ends properly into the groove of the chain
breaker, such that the roller which was pressed outwards is now pointing
towards the end of the flat-ended screw, you can begin to tighten that
screw. It will make contact with the roller and will begin to press it
back into the chain. Again, use the half turn in, quarter turn out method
to ensure that roller and holes always have the opportunity to align with
each other. From the far side of the chain, insert a small pin, maybe
a thin allen wrench, into the hole of the link. This will help you to
align the holes of the two links which you are connecting. As you press
the roller further into the chain, your allen wrench will be pressed out
by the advancing roller. But that's OK, at least the holes are all
aligned. When the end of the roller has reached the side-walls on the
far-end, be particularly careful again. Advance the roller in small steps,
always letting off pressure in between. Make sure that the outer side-wall
does not bend too much! It may flex a little as the roller is being
pressed into the hole, but it should straighten itself again after the
roller end is through the hole. The key really is the slow advancement,
with the frequent letting off of pressure.