This Triumph Street Triple, fitted with a stubby A16 exhaust can, came in for a full ECU remap to get the fuelling to match the can. Looking at it we were a little concerned about the efficiency of the baffle – it looked very much like a Christmas tree – but in this case it worked well.
These triple cylinder engines are a little lazy in this guise, so we gave it a little more ignition advance to sharpen it up through the mid-range. We also switched off the lambda sensor (of course!) at the ECU, turned off the secondary air valve (the cat too had been removed by the owner) and adjusted the fuelling in the MAP (Manifold Air Pressure) sensor area. Most bikes, on the road, spend most of their time in this area of the ECU’s overall engine map, so it’s crucial to get right. We can measure when the bike is running in the MAP sensor area, and adjust everything with spot-on precision.
The net result? Peak horsepower grew by 4bhp, with a good dollop extra in the midrange and overall the bike felt much more responsive; instant snap when you gassed it, with zero hesitation from the engine.