Weight
Stock silencer is heavy, about 7Kg. Most aluminium (LV) and titanium (Akrapovic) twin silencer aftermarket systems come in at 5-6Kg and the stainless ones are 6-7Kg, so not as much of a weight saving as you’d imagine.

Single silencer system can dramatically save weight, even in stainless. An MTC stainless can is about 2.2Kg. Go for a titanium or aluminium one and its even lighter still, my Exan weighs 1.2Kg, even with link pipe and all the clamps and mounting gubbins only weighs 1.65Kg.

Fitting a single silencer not only saves weight, but frees up potentially a lot of extra space for fixed storage which we all know the T�n�r� is lacks, such as a tool tube.

Cats
Be careful, some twin slip-on systems have cats, such as the accessory Akrapovic. Almost all of the available twin systems can be supplied with or without cats to satisfy German TUV. So you’ll need to watch that if buying second hand.

As WeaveMcQuilt says, quite satisfactory results can be obtained by removing the cat from the stock silencer, both in terms of sound, fuel economy and performance.

Noise
Generally, as Gibbo has found out, a single silencer is going to be harder to silence than a twin. It is possible to get a quiet single-sider, but the can needs to be adapted to single use. I think one of the problems with the MTC single having a reputation for being loud is that it is exactly the same can as they supply with the twin silencer setup. A specifically designed can for use on its own will be better in this respect.

Performance
In basic exhaust tuning physics, a single can will lower the engine speed where peak torque is made and a twin will push it up the rev range. One setup is not really any better than the other in terms of power, the different setups just shift what power there is up or down slightly. There’s only about 500rpm difference, which will be hard to notice on the road.

Exhaust tuning is not that critical on single cylinder engines, so don’t expect much of a power gain if any at all. On a multi-cylinder bike tuning of the exhaust, headers and manifold particularly can make a massive difference.

TBH, as has been mentioned already, the biggest single improvement you can make to a totally stock T�n�r� is by fitting an O2 controller; throttle response and low down tractability will be improved beyond recognition. After that, intake improvements (air filter/snorkel removal/DNA stage1-2-3 etc.) and a Kev fuelling mod (or PC) will further increase smoothness and drivability, as well as give improved power higher up the rev range.

Of all the possible mods mentioned, changing the exhaust is the most expensive by far (excepting a PC5) and will offer the least improvements in power and drivability.

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