The suspension geeks at FFRC have been scheming on ways to transform
the prehistoric suspension on the DR650 into something worthy of a modern bike.
A while back, FFRC customized the rear shock with excellent results,
and tried the usual cheap mod of heavier fork oil up front with mediocre results.
But the second level improvements have been incredible -
the rear shock was already dramatically improved with their custom valving.
But now they've added a customized piston that
makes the rear suspension even more plush over small bumps.
And up front they have invented their Plex Valve which works so
well the old rod forks are now the equivalent of good cartridge forks!
The DR650 is now very plush over small bumps and corrugations,
and yet also handles extreme abuse like this 60-foot jump with ease.
As previously discussed, the rod forks are a very old inadequate design,
and the suspension at both ends is too soft and under damped.
Also the rebound and compression damping at both ends is badly out of sync,
it can't be fully solved with just using heavier oil. Usual upgrade
for the forks have been fitting 'emulators' or 'intiminators'.
Many riders report better performance, in combination with heavier springs.
However while they are adjustable,
emulators require disassembling they forks and modifying which many DR650 owners dislike.
Intimidators don't require taking your forks apart, but they do need a different
fork oil weight, as they are only affect compression damping, not rebound damping.
FFRC's chief suspension guru, James, has been designing state-of-the-art suspension component
for years, not only for all sorts of motorbikes, but rally cars and v8 racing cars as well.
So he wanted to create the ultimate stock fork upgrade... a custom valve that would
be the match of quality cartridge forks and could simply be dropped in,
adjustable if needed, would not require changing the fork oil.
And even better, it would work well with the stock springs.
James spent a lot of time developing the Plex Valves on their dyno machine, and also with
various riders testing suspension from easy riding through to the punishment of a motocross track.
It's hard not to rave about our different the DR650 feels with that smooth plush ride on any
tracks right through to the most challenging terrain you can imagine. FFRC's dyno and real
world testing suggest most riders will find the Plex Valves will suit the stock springs for riders
up to around 100 kilograms. It looks as though stiffer single-rate fork springs will only be
needed for heavier riders, a safari tank, or very aggressive riders. Previously we had discussed how
the dual rate fork springs are really badly designed, but the length of the Plex valve
compresses the softer part of the spring rate sufficiently to achieve the right amount of sag.
This dyno chart compares the results of the budget option of 15 wait fork oil with the
new Plex Valves. James has also included a set of Kayaba SSS forks from a YZF 450 which
are a very good cartridge fork. You can see how closely the Plex Valve mimics a cartridge fork,
although of course it's deliberately softer than the motocross fork. As mentioned,
the rear suspension was already brilliant after James created custom valving for the rear shock.
The addition now of a customized piston allows a wider range of settings with the shims,
resulting in an even more plush feel, which is still very progressive to avoid bottoming out.
FFRC decided to test their latest upgrades in extreme conditions before developing it for more
difficult riding conditions. So of course they took the DR650 to a motocross track.
They figured why not try a 50 foot tabletop jump?
They reasoned if their suspension mods worked well in those conditions and the
stock components held up okay it should also work well long-term for every day adventure riders.
All the test riders agreed the suspension was great, and even landing from the biggest jumps
was smooth, an impressive achievement given the stock fork springs are far too soft for
even easy dirt riding. When the DR650 is such a cheap bike to begin with, it
makes so much sense to spend the extra money and get an excellent suspension setup tailored
to your needs. And the DR650 will still be much cheaper than most adventure bikes in its class.