The following is a summary of an exhaust can test done by German magazine
MOTORRAD NEWS, edition Feb-2009. The exhausts were tested on the new '08 R 1200 GS models.
1. SR-Racing - 14 points (max. = 15)
Power: 109.7 hp / 7.750 rpm
Torque: 113.9 Nm / 5.750 rpm
Idle noise: 90 dB
Weight: 3.340 g
Dimensions: 550 x 150 mm
Material: SS
Price (in Germany): 564 Euro
* Power and torque graphs: Shines in the mid range, specifically from 3.800 - 5.200 rpm. A little torque dent around 4.500 is still remaining but no other exhaust eliminates it likewise well. For the rider there should be no power hole at all, since hp is climbing up around this area with the SR. In the low and in the upper range performance is comparable to OEM.
Summary: Juicy sound at moderate noise levels. Excellent crafting - the clamp is a little piece of art. Also the power curve is good, no other exhaust helps the torque dent at around 4.500 rpm better. For this work we award our buying recommendation to Mr. Bruckschaegel ( note: it is the exhaust guru behind SR-Racing).
2. LeoVince Evolution 2 - 13 points
Power: 109.8 hp / 7.750 rpm
Torque: 110.4 Nm / 5.500 rpm
Idle noise: 90 dB
Weight: 4190 g
Dimensions: 560 x 140 mm
Material: aluminium
Price (in Germany): 329 Euro
* Power and torque graphs: Hp and torque graphs are identical with OEM.
Summary: Power generally is pretty much on the same level as the stock exhaust, only at the top we found a bit extra: we measured the highest hp in this test field. Crafting and price are all right. And because the sound is levels are moderate - we award our price recommendation to LeoVince, even though the installation was not the easiest.
3. Sebring Twister - 12 points
Power: 108.6 hp / 7.750 rpm
Torque: 112.9 Nm / 5.750 rpm
Idle noise: 91 dB
Weight: 4.376 g
Dimensions: 560 x 140 mm
Material: aluminium
Price (in Germany): 428 Euro
* Power and torque graphs: Slight plus in between 4.000 - 5.000 rpm, otherwise the curves stay much in line with OEM.
Summary: Perfect fit and moderate noise levels with real deep sound are the arguments of the Twister. The power curve is decent, the dent at 4.500 rpm is slightly improved. All in all a decent value for the money, and therefore we award our recommendation.
4. Bos GTS/S - 11 points
Power: 109.6 hp / 7.750 rpm
Torque: 104.9 Nm / 5.750 rpm
Idle noise: 93 dB
Weight: 3.840 g
Dimensions: 580 x 140 mm
Material: aluminium
Price (in Germany): 449 Euro
* Power and torque graphs: Below 3.000 rpm significantly less Nm, from there onwards albeit improved power and torque remain always 3 - 8 % below OEM. From 7.000 rpm on par.
Summary: A well made can with perfect fit und gut top hp. The torque development is lesser convincing, in particular the lower range lacks Nm ( minus 9.9 Nm at 2.500 rpm, compared to stock). Mounting is a child's play, and the price is ok.
5. Laser Duo-Tech - 10 points
Power: 105.2 hp / 7.500 rpm
Torque: 112.7 Nm / 5.500 rpm
Idle noise: 90 dB
Weight: 4.500 g
Dimensions: 550 x 150 mm
Material: SS
Price (in Germany): 359 Euro
* Power and torque graphs: Up to 5.500 rpm identical to OEM, above 4 % below.
Summary: Lighter as the stock can and low priced. The crafting is ok, the sound is pleasant and not annoying at all. Problem: In the higher ranges hp are clearly behind the stock exhaust.
5. Akrapovic -10 points
Power: 104.7 hp / 7.750 rpm
Torque: 106.9 Nm / 5.500 rpm
Idle noise: 93 dB
Weight: 2.562 g
Dimensions: 520 c 150 mm
Material: titanium
Price (in Germany): 615 Euro
* Power and torque graphs: Until 5.200 rpm not much different to OEM, above ~ 5 % below.
Summary: Nobel material, finest crafting and competionless low weight are the plus points for the Akra can. We also found a powerful and juicy sound a really flawless appearance. But: There are 5 hp lacking, and the price is quite hefty.
5. HPE - 10 points
Power: 108.5 hp
Torque: 110.9 Nm
Idle noise: 94 dB
Weight: 4001 g
Dimensions: 600 x 150 mm
Material: SS
Price (in Germany): 719.90 Euro
* Power and torque graphs: In between 2000 - 3.000 rpm almost 10% lesser torque than OEM, from 3.000 - 5.800 rpm similar, from 5.800 - 7.000 rpm 2 or 3 % lesser, above similar again.
Summary: Power delivery of the HPE is okay. The installation can not convince, because of the badly fitting bracket. Additonally the exhaust is pretty noisy. But: For fans of double-cans one of the few alternatives.
6. BMW OEM - 9 points
Power: 109.2 hp
Torque: 112.9 Nm
Idle noise: 88 dB
Weight: 5910 g
Dimensions: 470 x 190 mm
Material: SS
Price (in Germany): 637.25
* Power and torque graphs: Except a dent at around 4.500 rpm constant increase of hp until 7.800 rpm, from 3.500 - 7.800 rpm always above 100 Nm, except the infamous dent around 4.500 rpm.
Summary: Everybody knows it - the factory exhaust is pretty good. Why buy another one? The aftermarket cans are lighter, sometimes deliver more power and better sound. Those who want a change will find a good alternative.
Comment: I would like to add my personal opinion. The magazine's published power and torque graphs speak for themselves: Except a dent at around 4.500 rpm delivery with the BMW can is top. The peak power and torque are also among the best, and that with the lowest noise level within this group. Except the SR-Racing and the Sebring none of the other products here have anything more to offer, ofte the opposite is true. The BMW can is made fully from stainless steel, therefore it should outlast the motorcycle. On the negative side is the high weight and of course the price. Both points which are the exact advantages of the aftermarket products. As a cheaper replacement for an accident can, ok. But better? Mostly not. The 9 points awarded for the OEM can be in a way a bit misleading.
* indicates my readings of the power and torque graphs as published by the magazine.
