Aprilia Futura - Rear shock
The Aprilia RST1000 Futura comes equipped as standard with a Sachs rear shock adjustable for preload via a knob below the seat on the left of the bike and rebound via a screw adjuster on the bottom of the shock.
Though the Sachs unit is not the best money can buy, it's not at all bad when new, although it can be a little overwhelmed sometimes two up and with luggage.
How long does it last?
Most
riders report that the shock can last a good 30,000 miles, depending on
how much weight it has to deal with on a regular basis. When it's worn
it loses its damping.
Is it rebuildable?
Talk to a suspension specialist but in theory it could be beefed up with a stiffer spring, but if it's true that the seal can't be replaced, there's no point in doing this with a shock that's lost its damping. However, at the time of writing, some UK riders have tracked down a specialist apparently able to service the shock - and with direct experience of the Futura's unit.
Details are on this thread:
Apriliaforum: Suspension unit rebuild
Here are a few more specialists for UK riders, though it's not known if they have any experience with the Futura's shock:
Both of these will also make you a replacement.
Replacement rear shocks
Wilbers apparently make the replacement shock of choice, especially in the US, where plenty of riders swear by them. Wilbers do a direct replacement and an upgrade, which is also adjustable for compression damping. Many US riders report that the Wilbers shock is a big improvement on the original.
Here's a link to what appears to be the main UK supplier: Solocourse
And here's a link to the US supplier:
