Rear suspension units, or shocks, are what give
a rider his or her ‘seat of the pants’ feel. Too hard
and the bike will skip over bumps and give an
uncomfortable ride which can make it feel like
your kidneys have done a few rounds in the ring.
Too soft and the back of the bike will wallow and
weave, bouncing its way around corners.
The theory is simple. As with the front forks, a
spring gives you bounce to be compliant over
bumps and adjusting oil flow in the shock controls
how fast or slow the oil moves, so adjusting the
damping and the way the bike reacts to the bumps.
From the late-80s and early 90s the rear
suspension on most bikes has been adjustable
for damping control as well as spring preload. The
problem is it didn’t seem like most manufacturers
really trusted us to tweak it ourselves because
there was often little difference between the
extremities of adjustment. Even today, the
adjustment on most units only affects a small
range of damping control.
The first step for getting the rear shock to work
for the kind of riding you prefer is to have a play
with the adjusters. Just as with the front suspension
above, the Owner’s Manual is a good place to start
if you want to have a go at tweaking yourself. Most
bikes are likely to have a preload and rebound (or
tension) adjustment at the rear, and possibly a
compression damping adjuster (most certainly
on a modern sports bike). Once again, the manual
will tell you which is which, and it’s worth checking
what the adjusters are currently set on; do this
by turning each adjuster fully inwards, counting
the clicks or turns as you go. If you bought your
bike secondhand it’s likely that the adjusters may
not be on the standard settings. Try the standard
settings to see if you feel an improvement. If not,
try a few clicks in either direction (making notes
so you know where you’ve ended up compared to
where you started). Most stock suspension units
are set up as a compromise for an ‘average’ rider,
so don’t expect wonders.
The standard rear shock on your bike may be
able to be serviced with fresh oil and gas, but
many are sealed for life. This can be especially
effective if your bike is more than a few years
old, and can be a cost effective performance
improvement, bringing life back to a tired rear
shock.
If that doesn’t give the result you’re after,
then the next step is replacement with an
aftermarket suspension unit.
The greater the range of damping adjustment
and the more resistance to fade under
hard riding a unit has the more you will pay.
Prices range from around $500 for a simple
replacement monoshock through to
KIWI RIDER 63