Air filter and airbox

Aprilia Futura – Air filter/ airbox/ air boot

The Futura is equipped with a pressurised airbox which sits under the fuel tank, with a disposable air filter element that can be replaced to get a modest power gain and increased intake noise.

K&N do a ‘lifetime’ replacement that’s easily available in the UK and EU, but there are plenty of other makes.

The table below (taken from from Ken’s Falco site – sadly eliminated when geocities was shut down) shows different filter options and is a useful comparison of various air filters available for the Futura:

Air Filter Options

FilterMaterialHeightIDPleat sizePleatsSurface area
Paper (disposable)114.3mm (4.5")98.4mm (3.875")12.7mm (0.5")922671 square mm
(414 sq. inch)
K & N
Oiled Cotton
unknown*unknownN/Acotton gauze1368 square mm
(212 sq. inch)
Cleanable -
no details
unknownunknownN/Acotton gauzeunknown
Oiled Cotton
unknownunknownN/Acotton gauzeunknown

(*If you have any of the missing dimensions above – let me know)

The K&N filter is also suitable for all Falcos and Milles up to 2001.

Futura and Mille R airboots

Futura and Mille R airboots

Another common modification is to replace the airbox rubber with one from an early Mille R, which is much less restrictive. and more or less a direct replacement.

The airbox rubber is clipped to the underside of the airbox. Some owners who have done this mod report the new air boot is a snug fit against the air intakes in the frame, but others find there’s a gap, which needs sealing to stop the bike sucking in hot air from the engine bay, rather than cool air via the air intakes.

Some owners have gone as far as a custom airbox, but that’s for those seriously devoted to tuning.

The most common airbox mod of all is ‘de-restriction’, which is dealt with on a separate page.

All these improvements will considerably increase the amount of air the engine can suck in, but to get the best out of them it’s advisable to re-map the ECU.

However, owners who use Tuneboy custom mapping report than a Futura using a K&N filter and Mille air boot still needs its mixture leaning out for best fuel economy. But if you’re in any doubt don’t take a chance – an over lean mixture can kill your engine.

Oil in the airbox

Sometimes you’ll find engine oil in the airbox. This is because the engine spits out excess oil into the airbox, which collects in a tube with a bung on the end. See the oil page for more info and how to stop this happening.