Kawasaki ZX-6R

Now, I may be laid up with a debilitating injury, but I'm still burning the midnight oil trying to find out the best bolt-on kit for ZX-6R owners out there. So in this spirit, I hustled the mechanically-minded Dave Smith off down to the Carbontek dyno shop with my ZX-6R, and a brace of different pipes to test.

First up was the Akrapovic Evo full titanium system that's been on the bike for the past two months. A super-light, beautifully crafted setup, it's the lightest of the three on test here (and the most expensive). The fi nal section of the link pipe is amazingly fat - suggesting a pipe ideal for race tuners in search of extra peak power. I was pretty pleased with the Akrapovic's blend of sound, looks, weight loss and power.

When first fitted, it made 118bhp at the wheel, six bhp over stock. On the test day it produced 116bhp at the wheel, giving us a good base figure for trying the other two pipes. An afternoon's spannering by Dave saw both the Micron Serpent Hydratech and Yoshimura Duplex systems bolted on and tried out.

The results are on the dyno sheet - and pretty interesting reading they are too. The Micron setup, with the Ultralite can fitted easily enough, but Dave had some problems getting the headers to fit correctly with the radiator mount. Run up on the dyno, the Micron gave an impressive 119.5bhp at the tyre, an increase of around 3.5bhp over the Akrapovic, and nearly ten bhp on top of stock.

The Yoshimura set-up looks a bit slack to begin with. It uses the standard Kawasaki mid-pipe between the weighty stainless headers and the titanium end can, and some of the welds are a tad untidy. But bugger me if it doesn't give as good power as the Micron. A tenth of a bhp more than the Micron, at a hundred or so rpm less, with a few bumps in the curves, the Yoshimura does much better than we expected.

The final variable was the fueling - the Power Commander on my bike had a map tweaked to suit the Akrapovic system, which makes the Micron and Yoshimura look even better. Some further time on the dyno would have improved the curves on the Yoshi and Micron even more. So, to sum up, the Akrapovic is the lightest by nearly half a kilo, looks the best, and looks most suited to further engine tuning.

The Micron is cheapest, makes joint-most power, and is midway between the Akra and the Yoshi on weight. The Yoshimura makes joint best power, is midway on price, and is heaviest. Now, ZX-6R owners, the choice is yours.