Aprilia Futura - Exhaust - Pre-silencer
The pre-silencer, also known as the breadbox or pre-muffler, sits under the engine and houses the catalytic converter.
It acts as a collector box for the exhaust gases before
expelling them to the rear silencer. It's held in place by springs on
the pipes and a single bolt to the rear of the engine. If this develops
a hole it can be welded relatively cheaply.
Some have modified it by cutting it open, removing the catalytic converter and welding it up again, but the consensus appears to be it's not worth doing. It liberates very little power and the exhaust note hardly changes.
Another option is to replace it. There are two options, and one of them is only available second hand.
The AF1 H-pipe is made in batches in the US and was developed to work without changes to the fuelling. Up until early 2009 It could be bought new from AF1 in the US. However the last of the latest batch has sold out and AF1 will only make more if the demand is there. Currently it is not available on their online store.
AF1 claim their H-pipe increases power and it certainly feels like it does, with usable grunt coming in from at least 1,000 rpm lower than stock. It also weighs less than half the original but I found it introduced a flat spot at about 5,000 rpm that will need a Power Commander to smooth it out.
You can use an H-pipe with a standard end can or with aftermarket ones. Some owners don't like the H-pipe and standard can noise, and I have to agree after trying this set-up and ended up putting the breadbox back on. I was fed up with the flat spot, but mostly with people telling me my bike sounded sick!
Because of the weight difference, the Futura feels a little more top heavy when first riding it after stock, but most riders soon get used to this.
The
second option is the Bef H-pipe, which came as part of the Bef full system.
Only a few full systems (including bigger bore link pipes) were made but
they seem to crop up for sale on auction sites quite often.
The system pictured came up for sale on e-bay in 2007, and Bef endcans (much more common)come up for sale quite often.
If you manage to get hold of one of these systems, you might find this installation guide useful. Instructions can also be found on Befbever's site in the Futura folder.
See also:
Remember that you may need to re-map to get the best out of the bike.
Page last modified: June 6, 2010
